Date: Tue, 23 Jan 1996 11:24:00 -0500 From: Dick.Finn@FNB.sprint.com Subject: Cutting bulkheads As a cost saving thought, I bought a pack of 100 utility knife blades four years ago and still have most of them. As they start to dull a little I take a swipe or two with a whetstone. The blades last forever! ______________________________ Reply Separator _________________________________ Subject: Chapter 4 Question (fwd) Author: marcz@hpwarhw.an.hp.com at INTERNET Date: 1/21/96 11:21 PM Larry Jansch writes: >O.K, what's the best tool/technique to cut the bulkheads out of the 0.2" >hi-density foam? They're all traced out and I was going to use an Xacto >knife saw and metal straightedge, Knife, or knive saw? The knife would be OK From: Marc J. Zeitlin Subject: Re: Hot-wire saw Date: Wed, 31 Jan 96 16:54:08 EST Dick Finn wrote: > The hot wire saw in the plans has a low tension on the wire. This > problem is amplified when the wire heats up. The low tension causes a > lag in the center of the wire when drawing it through the foam. I > borrowed a saw from a fellow in my EAA chapter that used a high > tension stainless steel wire. Worked fantastic! I believe I've seen > plans for saw advertised. It'll be a while before you need it so keep > your eye opened for a set of plans or a loaner. Here's what I did: =----- = ----- = ----- Tension spring Pivots at the = ------ X's = 2"x4" ----- X=======X============================ = = = = 2"x4" = = 2"x4" = = = = =---------------------------= 0.025" SS wire As the wire heats up and expands, the spring pulls it taut via the pivots (just drywall screws). I went overboard with the 2x4's - they're heavy, so I lightened them up by drilling them out with a hole saw. The second pivot point lets me lengthen the saw for longer pieces of foam. Cost about $4.00 for the wood, spring, and wire. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Mon, 4 Mar 1996 21:29:23 -0500 From: JQUESTCOZY@aol.com Apparently-To: cozy_builders@hpwarhw.an.hp.com (cozybuilders) ---- Forwarded message: Subj: TID BITS OF INFO Date: 96-03-04 21:15:41 EST From: JQUESTCOZY To: JQUESTCOZY 1) Something I didn't know for those of you considering an IO-360. The lastest issue of KITPLANES talks about the new RV-8 and it's has a 200-hp Lycoming IO-360-A16D, anyhow the article goes on to state the -A16D fuel consumption is less than a carburetted 0-360 at equal power.(call me an oaf cause I didn't know that) 2) Wicks sells a nice Oilite bushing for $3.45 that has a 1/2 ID and a 5/8 OD and flange. I didn't like the idea of the rudder tubes chafing on the NG-30's so I opened up the holes to 5/8 and floxed bushings in. P/N is FB810-04 page192 of cat. (work nice) I installed after the NG-30's and floor were installed ,but it would be easier to do before the NG-30's are installed due to the floor being close to the drill chuck. 3) To remove rudder pedals after 5/8 tube has been cut to fit: (I used a 10-32 bolt with a 1/4 head(for socket) and a 12 inch extension to remove or install rudder pedals I I I I NG-30's I I side I I rudder pedal I I I I I I l l l l___________________I ______I I__I I I I L__________________I _I I_____ I I____I -----I I I I I I I I I----------------------------------------------I I ___ _______________________________ I --- __ _I_______________________________I 1/4 12 in. 1/4" extension socket Excuse the artwork but the 12 in. extension and socket will fit thru the NG-30 and reach the 10-32 bolt at the side to remove or install rudder pedals if you already cut 5/8" tube to fit between the pedals. Mine was only about .25 from the NG-30's which wouldn't allow enough room to pull tube out of the side sleeve after glassing over the rivet at side. You could most likely use a allen bolt if you don't have a 1/4" head 10-32 bolt (so socket will fit thru 5/8" tube) I hope this made some sense to somebody :-) 4)Having as much trouble as me getting a smooth bead of micro in a corner using a tongue depressor or popsicle stick? Try putting your "blob" of micro on a sheet of wax paper and make a hole in center and use it like a baker would to ice a cake(I forget what that tool's called they use) Paper tear on you? no problem just put another sheet around tear and make another hole. Not as good as a caulk gun but better than a stick for bigger jobs.:-) 5)Here's a very simple tool but the one I use the most. (Just a sanding block) ____________________________________ I I I (2) -8 or -10 holes for screws I 2.5" I o o <1"> I I I ________ I____________________________________I I________I 3/4" <-------------------------- 8" ----------------------------> < 2 1/2" > <----2"----> _________ I I Make (2) one for each side to hold the sandpaper down. I I 2.5" I o < 1" I I I I________I This sanding block only take a little time to make and you can use whatever straight board you have around. I countersunk the -8 or -10 screw and micro'd and sanded flush on bottom and use "wing nuts" to hold the small wood pieces that hold the sandpaper in place for quick changeouts. Also a 11" piece of sandpaper is just the right lenght for this block(just rip it with a straight edge and utility knife 2.5 in wide). I buy 36 grit sandpaper at a hardwood floor store that comes in rolls 8" wide and as long as you want. When it gets filled, it vacuums out debris well from paper. Make it what ever size you like.:-) I think the wing nuts are the best feature for quick change out of the paper. I use this all the time for getting straight edges on bulkheads or 1000 other uses. I hope you can use some of these ideas. John Wilemski (JQUESTCOZY) cozy #227 Date: Fri, 22 Mar 1996 12:06:11 -0500 From: william l kleb Subject: drill bits since the builder's manual "necessary equipment list" affords me the excuse, i am in the market for some new drill bits, both the wire gauge and standard fractional sizes. does anyone have any good sources or comments about quality, material, etc? --- bill kleb (w.l.kleb@larc.nasa.gov) 73 bellanca 7gcbc citabria 99 kleb cozy iv From: Marc J. Zeitlin Subject: drill bits (fwd) Date: Fri, 22 Mar 96 13:38:57 EST bil kleb writes: >since the builder's manual "necessary equipment list" affords >me the excuse, i am in the market for some new drill bits, both >the wire gauge and standard fractional sizes. > >does anyone have any good sources or comments about quality, >material, etc? I bought a full set of Titanium Nitride coated number (wire), letter, and fractional from ENCO Mfg. for $39.95, WITH a drill holder case. They're seconds (some are shorter than the standard jobber length) but they work just fine. ENCO is a supplier of cheap machine tools to machine shops, but they do mail order and take credit cards. They're at: 1-312-745-1500 ask for a catalog. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: 22 Mar 96 14:25:31 EST From: "William E. Buckley" <74744.2301@compuserve.com> Subject: Drill Bit/Tool Source Bill Kelb asked about a source of drill bits. I bought a set of the wire gauge bits from Harbor Frieght Tools for $18.00. They have higher quality bits (read -- more expensive) available. Their catalog has a tremendous amount of tools available for excellent prices. I've ordered several other things from them. They have great prices on the 1" and 2" chip brushes. Their number is 1-800-423-2567. Fax 1-800-905-5220. William E. Buckley (COZY IV #437, Chap 6) Date: Fri, 22 Mar 1996 14:28:00 -0500 From: Dick.Finn@FNB.sprint.com Subject: Re: drill bits Hello everyone! I bought a set of drill bits (I think there were 154 in a steel case) from Harbor Freight Tools. I've seen several tool/supply catalogues with the same set at the same price ($49.95 with a titanium coated set for something like $65). I'll look and see if I still have the catalogues and forward the contact info. I've been heavily involved in woodworking and cabinet making as a hobby for about 20 years and am on a ton of catalogue mailing lists. I'll pull some of these out and forward the names as reasonable priced suppliers of tools and supplies. Dick Finn Cozy Mark IV #46 ______________________________ Reply Separator _________________________________ Subject: drill bits Author: owner-cozy_builders@hpwarhw.an.hp.com at INTERNET Date: 3/22/96 1:08 PM i am in the market for some new drill bits, both the wire gauge and standard fractional sizes. does anyone have any good sources or comments about quality, material, etc? --- bill kleb (w.l.kleb@larc.nasa.gov) Date: Thu, 30 May 1996 10:33:27 +0000 From: Eric Westland Subject: Re: COZY: Cutting AL I second Michael's comments. I had a Sears jig saw that I had bought when I was in jr. high. It still works, but I bought the Milwaukee jig saw for about the same money Michael paid and there is no comparison with the Sears - worth every penny. I also have one of the imported bandsaws that I use to cut aluminum as well as wood. I bought a pot metal pulley for the lower wheel that has about twice the radius of the one it replaced to slow the blade speed down and it works well, although it will wander. Eric Michael Antares wrote: > > To add my comments to the already sizeable number of great methods: > > In the beginning when I had to make choices of what tools to buy with the > very limited amount of money I had, I pondered a long time about the > purchase of a band saw. I finally decided to buy the best jig saw I could > get (the one I chose was a Bosch 1587VS). It cost about $160 at Post Tools. > I have never regretted that decision. A year and many chapters have gone by > and I have used the saw for cutting everything from the 3/4 inch table top > and 4 inch table legs to 1/4 inch AL. It has never let me down. It is a > far cry from the $50 Sears variety that I used to use (not to disparage > Sears!). It would be nice to have a table saw and a band saw but for those > of us on a limited budget and without those tools to start with, I highly > recommend trying the GOOD jig saw method first. > > 6077 Old Redwood Highway > Penngrove CA 94951 > 707.664.1171 > > Finished through chap 14 except > chap 13. Currently on 16, 17 and > 24. Date: Thu, 30 May 1996 09:30:32 -0500 From: graf@ectss2.jsc.nasa.gov (Jonathan Graf) Subject: COZY: Cutting 1/4" Al Just wondering. What method have you guys ( Oh, wait that's improper Texan ), I mean ya'll been using to cut the 1/4" thick aluminum for the firewall hardpoints? I'm just a beginner and need some experts' advice. Thanks Jonathan Graf graf@ectss2.jsc.nasa.gov Date: Thu, 30 May 1996 09:35:10 -0500 From: campbell@ee.umn.edu (prof S. A. Campbell) Subject: COZY: Cutting 1/4" Al You can certainly do it with a hacksaw and a vise. It's tedious and not terifically accurate, but I have done some cuts this way. Much better or course is a bandsaw. We have such a tool at work and I have been know to bring my more demanding cuts in to do them. You can buy a bandsaw of course. This would be quite handy, but not really essential. There just isn't that much that you need it for. Steve Campbell Chapter 8 - Cozy #436 From: "Dalrymple, Mark J" Subject: COZY: CUTTING .25" AL Date: Thu, 30 May 96 08:51:00 PDT Another way to cut the .25 AL hard points is to use a jig saw with a metal cutting blade. Also as someone else had mentioned, you can use a belt sander. The sander with approx 50 grid can clean up and plane almost any AL rough cut. See Ya'll Mark Dalrymple (in short "Mark from Orange") Plan # 361 & Building WIngs Ph#714-538-4622 Date: 30 May 1996 09:00:22 -0700 From: "Judd Stewart" Subject: COZY: Cutting Aluminum FYI, I use a table saw, bandsaw and powered 10" miter saw to cut all my aluminum. The table saw and miter saw have carbide blades which cut the aluminum just fine, the finished cut is extremely good with minimum saw marks. I think you can cut any non-ferrous material with a carbide blade as long as you adjust your feed rate ( read:take it slow) The bandsaw is used for scroll work but the damn thing will never follow the line!!! judd_stewart@cpqm.saic.com Date: Thu, 30 May 96 11:07:37 EST From: MISTER@neesnet.com Subject: Re: COZY: Cutting 1/4" Al J Graf writes: >>>"What method have you guys ( Oh, wait that's improper Texan ), I mean ya'll been using to cut the 1/4" thick aluminum for the firewall hardpoints?"<<< I've found a bandsaw (I've got a small Sears Craftsman one) to be very useful. If you get the propoer blade it cuts aluminum like butter. I use it to rough cut things and then I bring them down to size using one of those combo belt/disk sander units. That sander has seen a lot of service over the course of the project. Bob Misterka N342RM From: Dick_Finn@em.fcnbd.com Date: Thu, 30 May 1996 11:29:39 -0500 Subject: Re: COZY: Cutting 1/4" Al This is a Mime message, which your current mail reader may not understand. Parts of the message will appear as text. To process the remainder, you will need to use a Mime compatible mail reader. Contact your vendor for details. --IMA.Boundary.194374338 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Description: cc:Mail note part RFC-822-Headers: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Precedence: bulk --IMA.Boundary.194374338 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Description: cc:Mail note part I put some masking tape over the aluminum (both sides) and draw the shape to be cut out on the tape. This minimizes scratching. Generally speaking I use the bandsaw to cut the metal slightly over size. I follow up with filing to the final shape/size. For tubing I wrap masking tape around the tube and pencil in the cut line around the full circumference. I again use the band saw but I rotate the tube continually rather then cutting straight through. This prevents the blade from wondering. I try to keep the aluminum cool by continually dipping it in water. I don't know that this is needed but have read that over heating can destroy the temper. A hack saw will work on some of the cuts but I feel a band saw is preferable. Dick Finn Cozy Mark IV #46 DICK.FINN@FNB.SPRINT.COM ______________________________ Reply Separator _________________________________ Subject: COZY: Cutting 1/4" Al Author: owner-cozy_builders@hpwarhw.an.hp.com at INTERNET Date: 5/30/96 10:49 AM Just wondering. What method have you guys ( Oh, wait that's improper Texan ), I mean ya'll been using to cut the 1/4" thick aluminum for the firewall hardpoints? I'm just a beginner and need some experts' advice. Thanks Jonathan Graf graf@ectss2.jsc.nasa.gov --IMA.Boundary.194374338-- Date: Thu, 30 May 1996 09:53:07 -0700 From: Michael Antares Subject: COZY: Cutting AL To add my comments to the already sizeable number of great methods: In the beginning when I had to make choices of what tools to buy with the very limited amount of money I had, I pondered a long time about the purchase of a band saw. I finally decided to buy the best jig saw I could get (the one I chose was a Bosch 1587VS). It cost about $160 at Post Tools. I have never regretted that decision. A year and many chapters have gone by and I have used the saw for cutting everything from the 3/4 inch table top and 4 inch table legs to 1/4 inch AL. It has never let me down. It is a far cry from the $50 Sears variety that I used to use (not to disparage Sears!). It would be nice to have a table saw and a band saw but for those of us on a limited budget and without those tools to start with, I highly recommend trying the GOOD jig saw method first. 6077 Old Redwood Highway Penngrove CA 94951 707.664.1171 Finished through chap 14 except chap 13. Currently on 16, 17 and 24. Date: Thu, 30 May 1996 19:41:52 -0400 From: PBurkha238@aol.com Subject: Re: COZY: Cutting 1/4" Al In a message dated 96-05-30 10:45:01 EDT, you write: > You can buy a bandsaw of course. >This would be quite handy, but not really essential. There just isn't that >much that you need it for. Just to beat this dead horse a little further, I've just recently installed my engine baffling and used the band saw to cut all of the intricate cuts. due to the thin nature of the aliminium in this area I dont believe a jig saw would be the ideal cutting instrument. The band saw has worked just about perfect for all of the aluminium. Paul Burkhardt Date: Thu, 30 May 1996 19:49:34 -0700 From: Michael Antares Subject: COZY: Cutting AL No question that the bandsaw is superior to a jigsaw for cutting thin material since it's always cutting downwards which holds the material against the table. I haven't tried to cut thin material with the Bosch so I'll do a little experiment with some 1/16th AL and see what happens. I'll give a report in the next day or so. 6077 Old Redwood Highway Penngrove CA 94951 707.664.1171 Finished through chap 14 except chap 13. Currently on 16, 17 and 24. Date: Fri, 31 May 1996 00:28:10 -0400 From: Lenpilot@aol.com Subject: COZY: Cutting Al On the subject of bandsaws and jigsaws, I was wondering if anyone has used a scrollsaw to any extent in their building. It seems that a good scrollsaw could be usefull in the detailed cutting. I have priced them, and a good one can be bought for just under $200. Since I am just starting out, I haven't bought a bandsaw, and I was curious which would be a better way to go. Leonard Farneth lenpilot@aol.com Chapter 4 From: Lee Devlin Subject: COZY: scroll saws Date: Fri, 31 May 96 9:11:02 MDT Leonard wrote: > On the subject of bandsaws and jigsaws, I was wondering if anyone has used a > scrollsaw to any extent in their building. It seems that a good scrollsaw > could be usefull in the detailed cutting. I have priced them, and a good one > can be bought for just under $200. Since I am just starting out, I haven't > bought a bandsaw, and I was curious which would be a better way to go. I bought a scroll saw about 2 years ago (a variable speed Dremel with digital readout) and haven't found it to be particularly useful in working on the Cozy. The problem may be my technique, but I have a terrible time trying to make straight or gradual radius cuts. It's OK for small radius cuts, but most of the Cozy parts have larger radii. This past weekend I bought a little 10" Delta band saw and found it to be much faster and easier in cutting the wooden cradle jigs for the canard than the scroll saw. It only cost $136 on sale, about 1/2 of what I paid for the scroll saw. If I had to do it over, I'd probably skip buying the scroll saw. Lee Devlin Date: Fri, 31 May 1996 11:30:00 -0400 From: Dick.Finn@FNB.sprint.com Subject: Re: COZY: Cutting Al Leonard, I'm a woodworking hobbiest (furniture, cabnetry, etc.) from way back. That made things a lot easier when I started the Cozy in that I already had most of the tools I needed. After about 25 years of wood working and 4.5 years of plane building I have not purchased a scroll saw. In woodworking it is, in my opinion, a rather specialised device. Some friends are very into arts and crafts types of projects and find it very usefull. Its great for tight curves and rather soft materials (i.e. wood or thin metal) I found little need for tight curves in the metal pieces. It would have been handy on a couple of pieces but these can be worked by making repeated cuts and filing to the final shape. Some of the metal would be difficult to cut on a scroll saw (aluminum or steel tubing or rod stock). I would suggest a band saw. Sears is usually a good choice for reasonable quality and availability of replacement parts. Another option is Grizzly or one of the saws from Harbor Freight Tools if you plan to just use it for the plane and want to save a buck. I have purchased some cheap tools and find that they are generally servicable if you take your time on the setup. My $.02. Dick Finn Cozy Mark IV #46 DICK.FINN@FNB.SPRINT.COM ______________________________ Reply Separator _________________________________ Subject: COZY: Cutting Al Author: owner-cozy_builders@hpwarhw.an.hp.com at INTERNET Date: 5/31/96 12:46 AM It seems that a good scrollsaw could be usefull in the detailed cutting. I have priced them, and a good one can be bought for just under $200. Since I am just starting out, I haven't bought a bandsaw, and I was curious which would be a better way to go. Leonard Farneth lenpilot@aol.com Chapter 4 Date: Fri, 31 May 1996 18:31:29 -0400 (EDT) From: Randy Crutfield Subject: Re: COZY: scroll saws I have gone the Scroll saw route, and like it so far. I bought the Sears Contractor grade, with a 20" throat (you can cut 20" into a piece before you run into the arm of the saw. I have owned a Dremel Scroll saw since I was a kid and tried using it, but it has too much vibration and does not have variable speed. The comparison between it and the Contractor grade saw from Sears resembles the difference between the jigsaws in the earlier discussion. I have used the Sears saw for the Aluminum hardpoints, tubing, etc. and it has performed well. It only cuts on the downstroke so it tends to hold the work-piece to the table as long as the rate of feed is correct. An advantage that it has over a bandsaw is that you can use very thin blades, yielding thin kerfs and tight radii. But boy when one of those blades breaks and you are right there over the workpiece it puts a little excitement in your evening. The table tilts and rotates allowing you to cut just about anything that you can think of. The disadvantage is that it is a scroll saw. It was not meant to cut long straight lines and it takes considerable attention to do so. You have to be very careful that you are not forcing the workpiece sideways into the blade as you attempt to get back on your line, because the blades are very thin and will flex sideways. The table does not have a recessed guide like a table saw or bandsaw to aid in straight cuts. Knowing all this, I still decided to go this route and haven't regretted it yet. Like others have mentioned, I learned early in this project to cut close to the line and sand to get it exact. I'm sure that someone out there has perfected eye/hand coordination to the point of being able to cut a straight line over and extended distance, but I haven't. Randy Date: 03 Jun 96 11:00:35 EDT From: Rick Roberts <102503.1561@compuserve.com> Subject: COZY: Cutting Aluminum I used to cut aluminum on my table saw with a standard carbide wood blade, and it does work, but it's a pain. I went out and bought a Freud (sp?) non-ferrous metal cutting blade and it cuts aluminum like butter. An excellent $60 investment. Rick ---------- Forwarded Message ---------- Judd Wrote: FYI, I use a table saw, bandsaw and powered 10" miter saw to cut all my aluminum. The table saw and miter saw have carbide blades which cut the aluminum just fine, the finished cut is extremely good with minimum saw marks. I think you can cut any non-ferrous material with a carbide blade as long as you adjust your feed rate ( read:take it slow) The bandsaw is used for scroll work but the damn thing will never follow the line!!! judd_stewart@cpqm.saic.com Date: Mon, 3 Jun 1996 23:51:50 -0400 (EDT) From: Bill Walsh Subject: Re: COZY: Cutting Al On Fri, 31 May 1996 Lenpilot@aol.com wrote: > > On the subject of bandsaws and jigsaws, I was wondering if anyone has used a > scrollsaw to any extent in their building. It seems that a good scrollsaw > could be usefull in the detailed cutting. I have priced them, and a good one > can be bought for just under $200. Since I am just starting out, I haven't > bought a bandsaw, and I was curious which would be a better way to go. > > Leonard Farneth > lenpilot@aol.com > Chapter 4 > Leonard, I bought one ofthe saws your talking about and have used it considerably and did not get a band saw (bad decision, that I will soon rectify) Get the band saw and a hand scroll saw for the intricate stuff. There will be plenty for you to do with the bandsaw as you progress. Especially when into the final "hardware "stages. my 2 bits Bill W Date: Tue, 18 Jun 1996 16:24:17 -0600 (MDT) From: "aka Mr. Radon" Subject: COZY: Re: Epoxy box with heater. I know I'm not the first to post something like this, but when you get something to work real cheap why not brag and share the info. I really got the idea from Lee out here in Colorado when I saw his neat little epoxy box with heater. He needs it a little more then I do, he works mostly in his garage and it gets cold out here in the winter. He had a light bulb installed inside of an insulated (foam) box which also held his epoxy pump. A neat little bread board device he had made cycled the light to maintain about 85 F (I think) inside the box. I made sort of the same thing, except I used a $10 thermostat switch used for electric heaters. It has a little dial on it so you can adjust the temperature in the box. I made the box out of some discarded foam insulation (They are building new houses across the street, good source of nails too!) Right now it is doing fine, and cycles on at 85, off at 90. I figure that for $10.00 (I had the other parts laying around from my bathroom remodeling job) that it was worth it. I just could never figure out a cheap way to cycle the light. Hope this wasn't too long and helps. ROY ============================================================================= Roy H. Grossinger- ME grossinr@rastro.colorado.edu Cozy Mk IV #503; Chapter 4 ROY_GROSSINGER@Radon-hq.ccmail.compuserve.com CU's Go - 4; Hull Layup "A man's destiny is his character" | ___ | http://bechtel.colorado.edu/~grossinr |---------(>-<)---------| http://www.abwam.com/grossing / ~~~ \ o/ \o Date: 29 Jun 96 14:54:49 EDT From: "William E. Buckley" <74744.2301@compuserve.com> Subject: COZY: Hot Wire Voltage Controller1 For the electrical wizards out there . . . I'm gonna make my own controlling box for the hot wire saw. One question: Does it matter if the current through the 'saw' is AC or DC? Do I need to convert it to DC after I've stepped it down? Thanks dudes. William E. Buckley (Cozy Mk IV, #437, Chap. 9) 74744.2301@compuserve.com From: Marc J. Zeitlin Subject: COZY: Hot Wire Voltage Controller1 (fwd) Date: Sun, 30 Jun 96 10:39:32 EDT William Buckley writes: >I'm gonna make my own controlling box for the hot wire saw. One >question: Does it matter if the current through the 'saw' is AC or DC? >Do I need to convert it to DC after I've stepped it down? You shouldn't. The wire is basically a resistor. The controller that Wicks or Aircraft Spruce sell (for $14.95, I think) are basically incandescent lamp dimmers - they don't do any conversion, and my saw works fine. -- Marc J. Zeitlin Email: marcz@an.hp.com From: "Rob Cherney" Organization: Ellicott City, Maryland Date: Sun, 30 Jun 1996 13:11:07 -0400 Subject: Re: COZY: Hot Wire Voltage Controller1 (fwd) > From: "Marc J. Zeitlin" > Subject: COZY: Hot Wire Voltage Controller1 (fwd) > To: cozy_builders@hpwarhw.an.hp.com (Cozy MK-IV Builders) > Date: Sun, 30 Jun 96 10:39:32 EDT > Reply-to: "Marc J. Zeitlin" > William Buckley writes: > > >I'm gonna make my own controlling box for the hot wire saw. One > >question: Does it matter if the current through the 'saw' is AC or DC? > >Do I need to convert it to DC after I've stepped it down? > > and Marc J. Zeitlin replies: > > You shouldn't. The wire is basically a resistor. The controller that > Wicks or Aircraft Spruce sell (for $14.95, I think) are basically > incandescent lamp dimmers - they don't do any conversion, and my saw > works fine. I would recommend a step-down transformer between the output of the lamp dimmer and the hotwire. The transformer should have a 120 VAC primary, and a 24 VAC, 10 A secondary (approximately). The secondary winding of the transformer is connected to the hot wire. This transformer serves two purposes: it is for safety, and it allows you finer control over the wire temperature. +--------------------------------------------------------+ |Robert Cherney Home Phone: (410)465-5598 | |Ellicott City, Maryland e-mail: cherney@clark.net | +--------------------------------------------------------+ Date: Sun, 30 Jun 1996 14:57:11 -0400 From: StetsonE@aol.com Subject: Re: COZY: Hot Wire Voltage Controller1 In a message dated 96-06-29 14:58:39 EDT, William Buckley writes: << I'm gonna make my own controlling box for the hot wire saw. One question: Does it matter if the current through the 'saw' is AC or DC? Do I need to convert it to DC after I've stepped it down? >> Let me preface all this by saying that I am NOT an electrical wizard. But I have a Voltac variable voltage transformer from Yokoyama Electric Works that puts out 0-130 volts AC. On this unit I need no more than 40 volts AC for the long hot wire saw used for wing cores. You'll need the ability to vary the voltage to suit your tastes and conditions. 0-40 AC would seem to be sufficient. I just measured a 25" hotwire saw and it pulled about 7 amps. Would a longer saw pull more or less? Electricity isn't my strong suit. Canard Pusher Newsletter 29 page 8 gives a schematic for building a hotwire controller for under $15.00 (early 80's prices). Any VariEze or Long-EZ builder should have a copy of this CP. Sorry. I have the text of all CP's on disk, but not the graphics. If anyone wants a fax copy, let me know by private email. Stet Elliott stetsone@aol.com Perpetual Long-EZ Builder Date: Sun, 30 Jun 1996 18:35:20 -0400 From: Jim Hocut Subject: Re: COZY: Hot Wire Voltage Controller1 Stet Elliott wrote >..... 0-40 AC would seem to be >sufficient. I just measured a 25" hotwire saw and it pulled about 7 amps. > Would a longer saw pull more or less? > Actually, (assuming you're using identical wire to build the different length hot wire saws) to hold a given temperature you'll be pulling the same amount of current no matter what the length is. You'll have to run a higher voltage with a longer wire in order to push the same current. If it takes 10 volts for a 1 ft saw it will take 20 volts for a 2 ft saw, 30 volts for a 3 ft and so on. There, hope that's good for 2 cents Jim Hocut jhocut@mindspring.com Date: Sun, 30 Jun 1996 16:02:59 -0700 From: Michael Antares Subject: COZY: Hot Wire Voltage Controller1 Let me use my electrical engineering talent which so seldom happens building a Cozy! Using AC or DC is the same--actually by definition as the AC voltage is defined as so many volts AC RMS (root-mean-square). The RMS value will cause the same amount of heating as an identical DC voltage. The peak value of the AC voltage coming out of our outlet is approximately 167 volts (the square root of 2 times 120 which is the RMS value). However the main point I wanted to make (which has been made several times in the past) is to avoid using so-called auto-transformers (trade name VARIAC) because they provide no isolation. If you're working on a damp concrete floor and accidentally touch the hot wire there is the potential to get killed leaving someone else to have to finish your Cozy and have the pleasure of flying it. A 24 volt transformer is SAFE as was pointed out in a previous letter. A light dimmer has the same problem as the VARIAC; no isolation and potentially lethal. If you are able to work on a dry wooden floor, the risk is much, much less and perhaps worth taking but otherwise I just wouldn't take the chance. My two cents, Michael 6077 Old Redwood Highway Penngrove, CA 94951 707.664.1171 Systems engineering hardware/software From: garfield@pilgrimhouse.com (Garfield) Subject: Re: COZY: Hot Wire Voltage Controller Date: Mon, 01 Jul 1996 00:54:11 GMT On Sun, 30 Jun 1996 13:11:07 -0400, Rob Cherney wrote: >I would recommend a step-down transformer between the output of the >lamp dimmer and the hotwire. The transformer should have a 120 VAC >primary, and a 24 VAC, 10 A secondary (approximately). The >secondary winding of the transformer is connected to the hot wire. >This transformer serves two purposes: it is for safety, and it >allows you finer control over the wire temperature. Both excellent points, but are you sure 24vac is high enough? Stet Elliot just posted that his long saw ran about 40v, and that a 25" saw he had rigged pulled 7 amps. Lemmy see, if the wing saw is about 48" (his sig says LongEze builder...plans call for 48" saw), say that's twice the length of the 25" saw, approx. and still pulling 7 amps, that would mean the 25" saw would drop about 20v or so. I know, I know, these are only approx. but let's see where this leads. Might be interesting. O.K. If 25"=2' say, and drops 10v per ft. with 7 amps flowing, that means the resistance per foot is about (V=I x R) => R = 1.5 ohms/ft. That's pretty high...maybe he's using small diameter stainless safety wire. But watch. There be dragons here. I use Inconel 600...this is the stuff Alexander used to sell that doesn't stretch at heat like safety wire... (I have two diameters 0.032" and 0.041") which are respectively 0.62 ohms/ft and 0.36 ohms/ft (and if you consider the cross-sectional area of the two sizes, this is about the right proportion...resistance is inversely prop. to area). Now let's see what the voltages are. Well, suppose same power necessary to get same wire temperature, roughly, and Power = I x V. [Stet's example is say 70 watts/ft (7 amps x 20v = 140 watts for 2 ft of wire)]. Now, my two foot saw using the small diameter Inconel 600 is going to be *only* 1.2 ohms. And I am going to dissipate 140 watts, like Stet's, but my resistance is a lot lower, so I'll get the following: Same power means 140 watts = I x I x R, so my current I is going to go up to about 11 amps!, but my voltage is going to drop to about 13v. So by using Inconel, I get about 26v for the long saw, to Stet's 40v. Now why did I do all this; well, to illustrate that it depends on what kind of wire you're using, if that 24v 10amp transformer is going to work. To be safe then, assuming folks could be using either Inconel or safety wire, you might want to have a say 50V 15amp transformer in use. I went through the electrobatics just to say that if the wire is quite different, you need a bigger range. But with the above slight correction, your idea is a fine one, because it doubles the finesse you get on adjusting voltage, and 50v max is a lot safer than 110v. One more thing, assuming you aren't disgusted already, remember that the larger diameter Inconel wire is often used for longer saws. If we used it on the 48" saw, we would get: 280 watts (same temperature but twice as long a wire), but the 4' of wire is only going to be about the same resistance as before (4' x 0.36 ohms/' = say 1.5 ohms ). Power = I x I x R, so 280 = I x I x 1.5 => I is about 14 amps, and V is now about 20v. See, now that 50v 15amp transformer is still going to do just fine on both types of wires. Here's the problem: you could do the above with a 750-1000VA 2:1 stepdown transformer, (say 110 in, 60 out at 16 amps) but they're gonna cost ya about $100 at the least, new anyway. So if you want to be precise and safe, it's gonna cost alot more than the $20 bucks or so for a 15amp dimmer control. Is it worth it? I dunno. At least the analysis was free. 8) Garfield P.S. If someone build an electronic control that gave 0-50v at max 15amps, that would be best, but the market for such a beast is small. And yes, I confess, I am an E.E. Date: 30 Jun 96 21:28:35 EDT From: Rick Roberts <102503.1561@compuserve.com> Subject: COZY: Hot Wire Voltage Controller1 I'M CERTAINLY NO ELECTRICAL WIZARD, BUT I BOUGHT A SURPLUS VARIAC, ACTUALLY SEVERAL, FOR ABOUT $15 AND IT WORKS FINE. I SAW SOMEONE'S POST ABOUT GETTING SHOCKED BY THE AC. YOU'LL BE RUNNING ABOUT 30-40 VOLTS AT SEVERAL HUNDRED DEGREES. I KIND OF LOOK AT THE SHOCK POTENTIAL AS AN EXTRA REMINDER IF I'M SO INCLINED TO BURN THE DAYLIGHTS OUT OF MY HAND BY TOUCHING THE WIRE. IT REALLY WORKED, I DID IT ONCE, WHILE DOING THE CANARD, I NEVER HAD THE INCLINATION AGAIN. Sorry the above is in all caps I just noticed the caps lock is on. So I went through and fixed the small letters, but I didn't feel like retyping it. Later, Rick Roberts ---------- Forwarded Message ---------- For the electrical wizards out there . . . I'm gonna make my own controlling box for the hot wire saw. One question: Does it matter if the current through the 'saw' is AC or DC? Do I need to convert it to DC after I've stepped it down? Thanks dudes. William E. Buckley (Cozy Mk IV, #437, Chap. 9) 74744.2301@compuserve.com Date: Sun, 30 Jun 1996 19:31:28 -0700 From: Michael Antares Subject: COZY: Hot Wire Voltage Controller1 To clarify a point about using a Variac or light dimmer. The shock hazard is not from the measured output voltage applied to the hot wire which will probably be rather low (20 to 40 volts RMS). The shock hazard is from the lack of isolation. What this means is that even though the voltage between the two leads suppling the hot wire is relatively low and not a shock hazard, the voltage that might be between either one of those leads and ground, i.e. a damp floor, can be the entire AC line potential which is capable of killing you. A true transformer does not have this problem because the AC line input is isolated from the low voltage output. Continuing 2 cents... Michael 6077 Old Redwood Highway Penngrove CA 94951 707.664.1171 Cozy#413 Finished through chap 14 except chap 13. Currently on 16 and 24. Date: Mon, 01 Jul 1996 00:53:00 -0400 From: Jim Hocut Subject: Re: COZY: Hot Wire Voltage Controller Several good points have been made concerning the safety of using variacs, light dimmer controls, etc. for the hot wire control. Personally, my shop has a wood floor, and besides that I'm a macho builder that has no fear. But, if you're not endowed with these qualities, there's another simple solution that hasn't been mentioned yet - a ground fault outlet - available from most any home improvement type store for under 20 bucks. You can either replace your current outlet with one or put one inside a utility box and wire it to the end of an extension cord. Note - if you have OLD type wiring in your house that doesn't have a ground wire a ground fault outlet may not properly protect you, in that case go with an isolation transformer. Jim Hocut jhocut@mindspring.com Date: Tue, 16 Jul 1996 12:05:28 -0400 From: DFinn7971@aol.com Subject: COZY: Epoxy Pump Neil Clayton indicated that he was concerned about what appeared to be a smaller then normal stream of hardner coming out of his pump. On occasion I've noticed the same thing and have resolved the issue by cleaning the pump on a regular basis. When I get the level of resin/hardner down low and do not have to refill immediately for a large layup I generally pour the remaining stuff back in the can and clean the pump. For those of you who have never done this and have an interest, read on: 1. Empty both containers into the cans and put a cup under each output tube. Pump out the remaining resin and hardner. No sense in wasting anything! 2. use an open end wrench to take off the two output tubes. Be real careful as there is a ball bearing right behind them. This acts as a seal on the downstroke when the resin/hardner is pulled into a resevour (sp?). Remove the ball bearings and don't drop them. Experience indicates that they roll a long way and are very difficult to find on the floor. 3. Remove the pump handle and the pistons. Be careful not to damage the o-rings around the pistons. This is usually enough disassmebly to do a goodcleaning. There is a valve on the inside of the containers to allow the resin/hardner to flow into the resevour on the downstroke of the pump handle. It always struck me as somewhat fragile so I never took it out. The last ime I took the whole thing off of the base and used a scraper and sand paper to clean up the old set up epoxy that had dribbled onto the base. I rinse the pump and components completly in real hot water until the water flows through all pieces smoothly. Hold the output tubes under the hot water tap so the water flows through. I've found that there is sometimes a small blockage in the hardner tube. I dry all the parts with a paper towel and then finish the cleaning with MEK. After reassembly and filling it will often take a little fiddling to get things flowing smoothly. I hold two cups under the outputs and collect the resin and hardner until they are both coming out in good streams. The resin/hardner can then be poured back into the containers. I always finish off by making a small cup of epoxy and letting it set up overnight to make sure it hardens correctly. Dick Finn Cozy Mark IV #46 DFINN7971@AOL.COM From: Marc J. Zeitlin Subject: COZY: Epoxy Pump (fwd) Date: Tue, 16 Jul 96 13:45:26 EDT Dick Finn writes: >This is usually enough disassmebly to do a goodcleaning. There is a valve on >the inside of the containers to allow the resin/hardner to flow into the >resevour on the downstroke of the pump handle. It always struck me as >somewhat fragile so I never took it out. I just removed mine last week to clean the hardener bucket. It's actually not fragile at all, and can be removed with a deep socket wrench very easily. It wasn't clogged in the least, however, and really didn't need cleaning (although the bucket sure did). I did have to take it off to get the bucket off the pump, though. >........... I've found that there is sometimes a small >blockage in the hardner tube. As long as the backflow valve is working, this won't change the ratio. You'll get a higher velocity, smaller diameter stream, which could LOOK like you're getting less hardener although you're not. Maybe this was what Neil was seeing. >.......... I dry all the parts with a paper towel and >then finish the cleaning with MEK. The alcohol used for "hard-shelling" works well as a cleaner as well. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Tue, 16 Jul 1996 22:57:11 -0400 From: StetsonE@aol.com Subject: Re: COZY: Epoxy Pump In a message dated 96-07-16 12:10:41 EDT, Dick wrote: > When I get the level of resin/hardner down low and do > not have to refill immediately for a large layup I generally pour the > remaining stuff back in the can and clean the pump. This is a good idea, although I only clean my pump about once per year or so. I'm able to go this long because I check the ratio of my pump (by weight) every couple of months with an ammunition reloading scale (a former hobby of mine). These scales are extremely accurate. If you know of someone who reloads their own ammo, ask to borrow their scale. To get a really accurate reading you'll have to weigh the cups you're going to use before you fill them up, because they usually don't weigh the same. This will throw off the final readings. In a pinch, you could probably talk a gun store into doing it for you, although you'll have to make two trips, one to weigh the cups and one to weigh the resin and hardener. The hoppers on these scales is quite small so you'll probably have to cut the top half off of a standard dixie cup. Instead of cups, I've also used balloons. That way you can tie a knot in them so there's no mess. Stet Elliott stetsone@aol.com Perpetual Long-EZ builder Date: Wed, 24 Jul 1996 17:32:09 -0700 From: "Steven D. Sharp" Subject: Re: COZY: RUDDER CABLE ROUTING FOR HIDDEN BELLCRANKS (fwd) StetsonE@aol.com wrote: > > You'll need these tools to work in the belhorn cavity. Orthoscopic > surgery, like I said. > > Stet Elliott > stetsone@aol.com > Perpetual Long-EZ builder I agree with you 100%. I had to do some major "surgery" on my winglets' However, I used a 1/4" pneumatic die grinder w/ carbide burrs of assorted shapes. For cutting/sanding in hard to reach places I use a 1/4" 90 degree pneumatic die grinder (NORTHERN HYDRAULICS - about $50). I use burrs for cutting and "quick change" disc holder mandrels (WISKS p/n: TP382 (3" disc) and 36, 80, and 102 grit discs. It'll save ypu bunches of time - provided you have a compresser. Thought I'd add my tid bit into the pile. Steve Sharp Making a career out of building a COZY 3 place Email: cozyiii@earthlink.net Subject: COZY: Epoxy pumps - Do it yo'sef Date: Tue, 3 Sep 1996 16:12:47 -0400 (EDT) From: "Randy Smith" Hi, Well, the jig table is almost finished. I am about to order a whole bunch of stuff from Wicks and I wanted to clarify something. Their catalog lists epoxy pumps for about $225 or so. The pump part looks real similar to a brake master cylinder used by some of the local go-cart racers. Is this the case? If so, perhaps I can purchase some locally and calculate the arm settings for 44:100 (or whatever) and build it myself. Is there anything in unmixed hardner/resin that would be harmful to rubber o-rings or some types of metals? Anyone care to elaborate on these things since I've only seen them in pictures. Am I way off base here? -Randy --* --- -* **-* *-** -*-- -* Crash Rescue Team 7 - Don't PANIC! |Cozy MkIV| NCR General Purpose Computing Randy.Smith@ColumbiaSC.NCR.COM |---( )---| Global Support Center Voice 803-939-7648, V+ 633-7648 ___o/o\o___ West Columbia, SC 29170 "I am the way, the truth, and the life..." -JC From: Marc J. Zeitlin Subject: COZY: Epoxy pumps - Do it yo'sef (fwd) Date: Tue, 3 Sep 96 17:41:10 EDT Randy Smith writes; >Their catalog lists epoxy pumps for about $225 or so. The pump part looks >real similar to a brake master cylinder used by some of the local go-cart >racers. Is this the case? Similar, certainly, but there's also a one way valve. In a master cylinder, the fluid goes both ways, not out (hopefully :-) ). >... If so, perhaps I can purchase some locally and >calculate the arm settings for 44:100 (or whatever) and build it myself. >Is there anything in unmixed hardner/resin that would be harmful to rubber >o-rings or some types of metals? Certainly not to aluminum or stainless. Doesn't seem to hurt the O-rings that are on my pump (although after about 2 years it leaks about one drop a month from the resin side). Personally, I think it would take about $100 of materials (cylinders, valves, metal, plastic tubs, etc.) to build a pump, so I'd just buy it, but I think you could certainly get a homemade one to work. There's no rocket science involved here. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Tue, 03 Sep 1996 20:50:13 -0700 From: Paul Comte Subject: Re: COZY: Epoxy pumps - Do it yo'sef Randy Smith wrote: > > Hi, > > Well, the jig table is almost finished. I am about to order a whole bunch of > stuff from Wicks and I wanted to clarify something. > > Their catalog lists epoxy pumps for about $225 or so. Recently got my pump, it looks very "robust". Nice fit and finish too. I'm betting that in five years this pump will sell used for close to what I'm paying for it today. I also considered building a pump but decided I need to limit my efforts those that actually make airplane parts. Paul Date: Wed, 4 Sep 1996 18:19:16 -0400 From: SBLANKDDS@aol.com Subject: COZY: Epoxy pumps - build your own This is not an advertisement, but I recently purchased an AN-100 epoxy pump from J & B Products. This is an adjustable ratio pump, with very solid construction (vs sticky stuff dispenser). The designer is also an EZ builder! Buy direct from the manufacturer. Cost similar to the other one. Call J & B @ (954) 432-5196 or fax (954) 430-0956 The alternate is to build a balance as per cozy plans, and use some large pump bottles to store resin and hardner, this worked quite well, and was cheap, but i like toys, and the pump is a little faster. Both methods were accurate, I tested and restested the ratio delivered vs the scale. Steve Blank Port St. Lucie, FL Cozy Mk-IV # 36 SBLANKDDS@AOL.COM Date: Thu, 05 Sep 96 09:02:37 est From: "Larry Schuler" Subject: COZY: Epoxy pumps - Do it yo'sef Not off base. I have one of their pumps and it is basically the way you called it. Can't say what type o-ring they used, but the cylinders are aluminum and the pistons are steel. It uses some steel balls for valves. Haven't taken mine apart to clean yet; someone else might verify. It sure isn't complicated; I bought one because I wanted to build airplane parts, not tools. Larry Schuler MKIV-#500 From: Paul.Krasa-1@pp.ksc.nasa.gov (Krasa, Paul) Organization: Kennedy Space Center, FL Date: Thu, 05 Sep 1996 14:00:12 -0400 Subject: Re: COZY: Epoxy pump >I can understand that. This isn't wheel re-design, I simply am trying to save >a little money. You know for something really important like an engine, etc. >Its like Marc said, this isn't rocket science and I don't expect to spend a >large amount of time on it. I recently read somewhere that the pumps for WestSystems can be converted to give the right ratio for Saf-t-poxy. I'll try to figure out where I read this. It sure would be a cheap alternative. Paul W. Krasa Long EZ 214LP !---*---! Date: Thu, 05 Sep 1996 17:27:05 -0700 From: Chris van Hoof Organization: C van Hoof - Architect Subject: COZY: Epoxy pump Hi Randy Smith, "WE" went for the Rutan scale, this turned into an article of beauty, then during the bottom layup, the girlfriend (who worked the scale :)) decided that this would make an ideal Xmas present.....and I concede, it made life a lot easier and takes the off-chance error out of the picture. Since its almost December..... Also why spend time redesigning the wheel (pump :)) when you could be building........I keep track of my progress under different headings and can tell you that we spend almost 40% of our time on periferal work. (All the above is tongue in cheek) Have fun. chris #219 cvh@iafrica.com Date: Wed, 11 Sep 1996 10:23:32 -0700 From: Chris van Hoof Organization: C van Hoof - Architect Subject: COZY: Epoxy pump Hi Randy Smith, Was at a local epoxy shop today, during discussion the owner showed his latest... separate epoxy pumps that fit on the containers. This is made from plastic and looks like the dispensers sometimes found on handsoap, press once for a measure of fluid, this was altered to suit the volume required by adding a solid item in the chamber of the pump, and worked fast and showed no error on the electronic scale during testing. They looked like +/- 1.5" in dia and the volume pushed out on the resin was about 1/4 of the medium paper cup. The push was +/- 2". The price was real cheap, such that you could afford to throw away if neccessary. I don't know if it would be compatible with your epoxy but it is compatible with the Hexcell France epoxy 2022, 2023 and some others. Hope this is yet another solution :-). chris #219 cvh@iafrica.com, Date: Thu, 12 Sep 1996 10:09:33 -0400 From: william l kleb Organization: NASA Langley Research Center Subject: COZY: general purpose weights This is a multi-part message in MIME format. --------------446B794B15FB Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit i have been searching for decent weights for general shop use. the criteria were: high density, compact, and soft (won't scratch aluminum). i found them in the form of lead chalking which is sold at your local plumbing supply store. i got 10 five pound ingots for $40 ($0.80/lb). --------------446B794B15FB Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename=".sigeaa" --- bill kleb (w.l.kleb@larc.nasa.gov) 72 bellanca 7gcbc 9! cz4 -> aerocanard --------------446B794B15FB-- From: "Krasa, Paul" Subject: RE: COZY: general purpose weights Date: Thu, 12 Sep 1996 10:39:08 -0400 >i have been searching for decent weights for general >shop use. the criteria were: high density, compact, >and soft (won't scratch aluminum). > >i found them in the form of lead chalking which is >sold at your local plumbing supply store. > >i got 10 five pound ingots for $40 ($0.80/lb). I filled large heavy duty zip lock bags with sand then placed anouther bag over the first bag with the seal at the bottom of the bag. Works great for wieghting cores when hot wiring and it was CHEAP! From: "Steve Campbell" Subject: COZY: Weights Date: Thu, 12 Sep 1996 16:27:56 Building the Cozy has finally allowed me to use all those cans of paint that I have stored for 20 years in my basement (Autumn wheat, lemon yellow, *.. did we really paint our rooms those God awful colors?). Anyway they make great weights. I keep a dozen or so in my shop have have 6 or 8 of the more recent cans (ie after the Carter administration) in reserve. Works great and they're free. Steve **************************************** Stephen A. Campbell Associate Professor, EE University of Minnesota ***************************************** Date: Thu, 12 Sep 1996 15:21:10 -0400 From: DFinn7971@aol.com Subject: Re: COZY: general purpose weights In a message dated 96-09-12 15:08:09 EDT, kleb@ab00.larc.nasa.gov (william l kleb) writes: << i have been searching for decent weights for general shop use. the criteria were: high density, compact, and soft (won't scratch aluminum). i found them in the form of lead chalking which is sold at your local plumbing supply store. i got 10 five pound ingots for $40 ($0.80/lb). >> Weights are absolutely essential in building the plane. I found that you can't have too many. I use weights from my barbell set and window sash counter weights. When I need to distribute the weight I put them on pieces of wood. Dick Finn Cozy Mark IV #46 DFINN7971@AOL.COM Date: Thu, 12 Sep 1996 14:41:23 -0700 From: Michael Antares Subject: COZY: general purpose weights I heartily second the absolute desireability of weights. I got 5 pound lead ingots at the local OSH hardware store. I use them constantly not only for their obvious uses as clamp substitutes and holddowns but I've also used them as backstops to hold pieces of foam vertically while it sets up (the heater duct for example) and in the last couple of days I piled 40 pounds worth on top of a wing jig to force it into alignment while the Bondo set up. The lead ingots are somewhat expensive but other than uranium and gold you can't get more weight in less space! 6077 Old Redwood Highway Penngrove CA 94951 707.664.1171 Cozy#413 Finished through chap 14 except chap 13. Chaps 16 & 24 mostly finished. Now on chap 19. Date: Thu, 12 Sep 1996 23:01:49 -0400 From: SBLANKDDS@aol.com Subject: COZY: general purpose weights William Kleb wrote about purchasing lead for use as weights. Being a dentist, I found a very cheap source of lead for weights. FREE Every time we take an x-ray there is a lead backing inside the film packet that is considered waste. They are small, but leads is dense and adds up quickly. I save these and then use them. They can be put in baggies, or for foam cutting I use 2-3 coffee cans full to hold the block. If you want to be labor intensive, you can melt lead on a kitchen stove and pour it into a mold. Fisherman do it all the time. Do NOT melt them in a pot that you use for food cooking. Ask your local dentists to save the lead for you. They will probably be glad to get rid of the stuff. Steve Blank,DDS Cozy MkIV #36 Port St. Lucie, FL sblankdds@aol.com From: Lee Devlin Subject: Re: COZY: general purpose weights Date: Fri, 13 Sep 1996 8:54:18 MDT > If you want to be > labor intensive, you can melt lead on a kitchen stove and pour it into a > mold. Fisherman do it all the time. Do NOT melt them in a pot that you use > for food cooking. Be careful with this. Although trained human servo systems can easily carry a full cup of coffee while walking without spilling any, handling a pot of molten lead requires practice. A friend of mine tried to pour a ~20 lb weight by melting lead in a cast iron skillet, which is reasonable receptacle for the task, but all that heavy lead swishing around on a cantilevered CG resulted in a kitchen 'incident'. Suffice to say he had to buy his wife a new countertop and replace the lineoleum floor. He said he looked like the tin man from the 'Wizard of Oz' afterward. Fortunately the lead froze quickly after coating sensitive areas of his pants otherwise the story may not have had such a funny ending :-). Lee Devlin Date: Fri, 13 Sep 96 17:42:25 +0000 From: cac%exo.com@exo.com Subject: COZY: Lead weights If you are interested in melting your own lead weights you can go to the local gun shop that has re-loading supplies and get a mold to form ingots. You may want to try number 4 buck shot from the gun store as well, it will mold over curved surfaces well. Another source for lead is from indoor shooting ranges. You will want to dump a little bees wax into the liquid led to help collect the slag and them remove it before pouring. ////////////////////////////////////////////////////////////////////////////// // // // Cliff A. Carpenter // // Cozy Mk4 #280 // // // ////////////////////////////////////////////////////////////////////////////// From: Steve Hall Subject: Re: COZY: general purpose weights Date: Fri, 13 Sep 1996 20:54:18 -0400 Try stoping by your local "Dive Shop", They will have lead shot in various size mesh bags. Or your local sporting goods shop, they should have lead shot in 25 lb. bags. Then you can make your own size bags. I have been using bags of lead shot throughout my building, and have found that they distribute the weight the best with out leaving dents in the foam or distort wet glass. Whatever its worth,,,It works for me. Steve. Date: Fri, 20 Sep 1996 23:02:30 -0400 From: "William B." <74744.2301@compuserve.com> Subject: COZY: Hot wire Alright, crisis averted. Secure from General Quarters. Following the principle of "necessity is the mother of invention", I took matters into my own hands and came up with a solution to kinked (to put it lightly) safety wire. You guys are gonna love this one. First -- secure one end of the wire to your house. Second -- secure the other end to the front bumper of your truck. You can see this coming, can't you? Lastly -- slowly back down your driveway until the wire is pretty tight (if you tune it to the low E string on a guitar, that seems to be about right) and leave it for an hour and a half. When you're done, you have perfectly straight wire usfeful for hot-wiring. The added bonus is that this process really confuses the neighbors who are already suspisious of the guy who has a "boat with wheels" in his garage. Also, thanks to Dick Finn for offering some wire from your personal stash. Hopefully I'm back on track with what I've got. William E. Buckley (Cozy Mk IV, #437, Chap 10) 74744.2301@compuserve.com Date: Sat, 21 Sep 1996 10:47:54 -0700 From: Chris van Hoof Organization: C van Hoof - Architect Subject: Re: COZY: Customer Dissatisfactiojn William B. wrote: > > Ok . . . . . . I'm really beginning to loose patience with some of these > and when it got....... > here it looked like a bird's nest. ..... I couldn't cut > airfoil cores with a "serrated" hot wire saw. I'm so mad right now I > could spit...... > > There is nothing more frustrating than having a garage full a materials > without the ability to progress because of the absense of one item. > > William E. Buckley (Cozy Mk IV, #437, Chap 10) > 74744.2301@compuserve.com Hi William, Keep the fun side near the sun, here's an alternative possible fix. Fix/connect/adhere one end to a stationary end = house /vice / person the other end goes into a chuck of an electric drill, now stretch as far as you can and reverse/ walk back/ whatever to keep the tension and you will have the straightest wire in the county. This tip works with any plyable/bendable/ruinable lenght of most metals, and have personally used it with 1/4" alum round Hope this helps chris #219 in my playbox with Cozy in chapter 7 cvh@iafrica.com Date: Tue, 22 Oct 1996 15:55:40 -0400 From: william l kleb Organization: NASA Langley Research Center Subject: COZY: epoxy measuring / parts weighing a while ago i requested info on the scales people were using to weigh parts and measure epoxy a while ago. i thought it only fair that i pass on my experience: initially i bought a pelouze pe-5 postal scale from an office supply store (office max) for $90. it only read in lbs/oz which maked things a bit cumbersome when figuring epoxy ratios on the fly and the accuracy isn't good enough for mixing small batches of epoxy. i returned it. i bought an acculab v3000 toploader balance from precision weighing balances in bradford, ma (http://www.balances.com/) for $120 which does 3000g x 1g (6.6 lbs x.05 oz). The ohaus ls2000 is another option in the same class (2000x1g), but it didn't come with a stainless steel platform or ac adapter. using my hp ;) calculator, i made a table for the mixing ratio, so now i can mix up "fast" or "slow" versions of "safe-t-poxy" quickly, ie, without having to empty and refill my epoxy pump which is typically stocked with "regular" hardener. --- bil kleb (w.l.kleb@larc.nasa.gov) 72 bellanca 7gcbc 9? cz4 -> aerocanard Date: 23 Oct 96 19:33:23 EDT From: INFINITY Aerospace <72124.347@compuserve.com> Subject: COZY: Drill Bits Hi to All, >All laminates will chip/delam from drilling holes, to limit this sharpen the bit at a finer angle than 90 deg. I do my bits at about 40 deg. It gives it less bite.< One can buy drill bits specifically designed to drill fiberglass and plexiglass. The same for saw blades. Infinity's Forever, JD Home Page http://ourworld.compuserve.com/homepages/INFINITY_Aerospace Date: Thu, 31 Oct 1996 11:51:08 +0200 From: Rego Burger Subject: COZY: Builder Tips Some tips for all: 1. Used hacksaw blades (2" piece )make nice scrapers for non peel plyed areas before bonding. 2. Plastic cups make nice mixing cups - no wax like some paper cups. 3. Plastic bags flat on a table makes a nice wet out platform for tapes etc.( Ernie degovia, cape town ) 4. Used hachsaw blades make nice stiring sticks for mixing epoxy. ( just clean them first ) Happy Building Rego Burger Port Elizabeth RSA Cozy mk4 #139 Date: Fri, 08 Nov 1996 07:45:43 +0200 From: Rego Burger Subject: COZY: Spirit Levels and level lines. A little of my trials. ( call back the past ) While building the canard for the cozy I shortly after finishing the top skin decided to "measure" the twist tip to tip. I found over the 3.8m span that the one tip was a 1/4 bubble out on my spirit level. This was at 24:00hrs one night, I almost threw my nappies out of my cot. A twisted canard. I went to sleep on it ( the problem not the canard ) At work I gave it a lot of thought between tasks. One solution was to offset an elevator to correct the problem. On getting home my wife sensing I was troubled tried to calm me down when I started out to the workshop. " Don't worry " she said, " it will come right." I just kept quiet at her almost unbelievable statement. Alone in my sanctuary I closed the door and debated with myself the pro's and cons of my fixation with perfection. Was it worth all the stress. While I think things out I often play with a tool or pencil etc. This evening ( years back ) I was playing with the level. I placed it down on the work bench this way and that, I froze as I noticed the table seemed to be also a 1/4 bubble out of level. Then it happened, something made me turn the level around 180 deg. There it was, level! I had an inaccurate level. My wife's words were true, IT DID come right by itself! An accurate spirit level will read level in both directions not in one direction like mine. By accident ( or divine grace ) I had set it up with the level pointing the same direction during line up, but when checking the already set top skin I had inadvertently rotated the level 180 deg from left tip to right tip giving me the 1/4 bubble outage. Needless to say I never made that mistake again. I now have an arrow marked on the level to point forwards at all times, maybe you could pass on this tip to Nat for a newsletter? Check your spirit level before you check your level lines. Rego Burger Port Elizabeth RSA Cozy Mk 4 #139 Date: Fri, 08 Nov 1996 05:26:32 -0500 From: "Steven D. Sharp" Subject: Re: COZY: Spirit Levels and level lines. Rego Burger wrote: I almost threw my nappies out of my cot. -Okay? Is this good?? > I had an inaccurate level. Very common - Levels need to be checked on a regular basis I used water levels with multiple stations on the same level - dead accurate - at least within the diameter of tube I used. As long as your're straight and no significant twist you are good to go!! Thanks for the info Steve Sharp cozyiii@earthlink.net From: Epplin_John_A@hpmail1.90.deere.com Date: Fri, 8 Nov 96 08:18:27 -0600 Subject: COZY: Spirit Levels and level lines. I came by a machinists level some years back. These have several times the sensitivity of normal carpenters levels. You can be what you believe to be dead on with a 4 ft. carpenters level and place a machinists level over the carpenters level and be a full bubble off. I am not sure what accuracy is really needed but I feel confident that the machinists level is an over kill and am not sure of the carpenters level. The Starret level I have is graduated in increments of 1000 to 1 or about .057 deg of angle. The carpenters levels I checked were over 5 times this. It is a good idea to check you level by the 180 deg rotation method mentioned by Rego frequently. I have a 2 x 3 ft granite table I use for this. Any flat surface you can shim or otherwise adjust is OK however the heavier it is the better. John epplin Mk4 #467 by InfoAve.Net (PMDF V5.0-6 #4800) id <01IBMZ02R5JS8XJ7DV@InfoAve.Net> for cozy_builders@hpwarhw.an.hp.com; Sat, 09 Nov 1996 09:51:39 -0500 (EST) Date: Sat, 09 Nov 1996 09:51:39 -0500 (EST) Date-Warning: Date header was inserted by InfoAve.Net From: Nick Ugolini Subject: Re: COZY: Spirit Levels and level lines. > >An accurate spirit level will read level in both directions not in one >direction like mine. By accident ( or divine grace ) I had set it up >with the level pointing the same direction during line up, but when >checking the already set top skin I had inadvertently rotated the level >180 deg from left tip to right tip giving me the 1/4 bubble outage. >Needless to say I never made that mistake again. I now have an arrow >marked on the level to point forwards at all times, maybe you could pass >on this tip to Nat for a newsletter? Check your spirit level before you >check your level lines. > I agree. You can purchase an electronic level called "Pro Smart Level". It is accurate to 0.1 degrees. On a 48" rail, I have measured an accuracy of +/- 0.060". Periodicly, you can do a full calibrations of all directions, and daily you do a quick level reset. I love using it to check my carpenter levels. Sometimes I find that I have "recalibrate" my bubble levels. It has a bunch of different displays, such as, a visual bubble, direct degrees reading from level, % grade, and feet/foot. You can also set your own datum plane and measure angles or plum form the new plane. It has an electronic senor which you can place in diffrent "rails". I have a 24" and a 48" rail. They also make a 12" and 96" rail. I highly recommend the unit. Cost about $90 (including a 24" rail and case.) Nick Ugolini unick@mail.charleston.net Varieze N89RS Cozy Mark IV #0264 by SERV05.SLAC.STANFORD.EDU (PMDF V5.0-6 #10979) id <01IBPSMAB5A60016O2@SERV05.SLAC.STANFORD.EDU>; Mon, 11 Nov 1996 10:21:09 -0800 (PST) Date: Mon, 11 Nov 1996 10:21:48 -0700 From: hrogers@SLAC.Stanford.EDU (Howard Rogers) Subject: COZY: Re: Tool picture and alignment Michael, Thanks for the Jpeg and the explanation. I am always interested in the myriad of little solutions people think of for solving such problems. I fininshed my winglets some time ago, but I have no doubt that your method could be applied to similar problems, elsewhere. I will share one of mine with you. I was never happy with the use of bubble levels for such a critical task as wing and canard alignment. I borrowed a surveyor's transit/level from work, where we are used to aligning electron beamline components to the thousandth, over large distances. I set it up in the corner of the garage, leveled it, and now had the ability to optically sweep a "plane" over the whole construction area. By holding a ruler to the tops of templates, fueselage longerons, leveling boards, etc. I could sight through the "telescope" and adjust things till they were all positioned accurately, in relation to the optical plane, then bondo them in place. Everything on the EZ is aligned to much higher standards than the plans-methods would allow. I hope this pays off in flight. Another tip: The slickest method of forming nice fairings around the gear-leg to fuselage junction that I have ever seen works like this: Just pile on chunks of urethane foam and grow-foam around the junction. Make a big glob. Sculpt it to a large-radius graceful faring shape, holding to the slipstream direction as closely as possible. Glass over the whole thing (about 4 plies BID), and right up onto the fuse and gear leg. When this cures, of course, you have made a rigid thing out of a joint that must flex. Now, tape about 4 or six hacksaw blades together and make a continuous cut, just through the glass, all the way around your new fairing, just about midway between gear leg and fuse. Make the cut carefully, and parallel to the slipstream. You have now separated the whole shell into two pieces. The wide cut will allow them to move without catching on each other. The urethane foam will crunch around a bit, inside, but who cares? The glass shells will hold their shapes. The only decision that must be made is: Would you rather that this look perfect while the airplane is parked on the ground, or would you rather that it faired perfectly, while in flight? I plan to compromise. When I park, I will always lift up on a wing to "unspring" the gear, anyway. I will glass it up in that postition, which isn't far from its "in-flight" position. I did this exact setup for a friend on his formula 1 racer a few years ago, and it worked out beautifully. I didn't invent this, but I sure like it. hrogers@slac.stanford.edu (Howard Rogers: pilot, aircraft mechanic, saddle maker, high energy physics R+D handyman) _____________________________________________________________________ Do your part: Help stamp out the mindless, indiscriminate use of impersonal, cutesy "rubber-stamp" E-mail signatures. _____________________________________________________________________ Opinions are strictly mine, and are usually not those of my employer. Date: Tue, 12 Nov 1996 18:21:25 -0500 From: DFinn7971@aol.com Subject: Re: COZY: Spirit Levels and level lines. In a message dated 96-11-09 09:56:02 EST, unick@charleston.net (Nick Ugolini) writes: << You can purchase an electronic level called "Pro Smart Level". It is accurate to 0.1 degrees. >> I bought the Smart Level at OSH two years ago and consider it one of my better investments. I have two 48" and one 24" Carpenter Levels that I use too but I always finish up by checking with the Smart Level. It will read out in inchs of rise per foot as well as in degrees. I find this helpfull in setting up rough shims. Dick Finn Date: Thu, 21 Nov 1996 07:06:53 -0500 From: SBLANKDDS@aol.com Subject: COZY: AR-100 Epoxy Pump I purchased the AR-100 pump a few months back and the product a good value. Now they have a web page that has very good pictures of the pump. The text is very descriptive of the pump. Find them at: http://www.jbproducts.com p.s. An inexpensive home built balance is still acceptable. Steve Blank, Cozy Mark IV #36, Port St. Lucie, FL USA Date: Thu, 21 Nov 1996 15:19:44 +0200 From: Rego Burger Subject: COZY: Balance Scale >>p.s. An inexpensive home built balance is still acceptable. Steve Blank, Cozy Mark IV #36, Port St. Lucie, FL USA<< I agree with Steve, I had a KR-2 builder come visit me to discuss the validity of buying a pump system. I showed him my simple old balance scale. I feel I went a little further with it to a point. Because I do other odd jobs with epoxies I needed to mark different ratios on a slide rule type arm. The pivot is mounted on a bearing, this reduces friction well. I demonstrated to my keen observer , when asked how accurate is it. In the balanced position I place half a square from a tissue on the hardener arm, it drops like a brick! He then wanted a demo with "REAL" liquid. With water demo it dropped after 3 drops. I feel it's worth it's money, the whole scale cost me R 15-20 in 1991.( $4-00 ) Once a month I blow out any dust in the bearing ( a sealed one was going to cost me too much R 9-00) then light oil and back to work. Maybe some early starting builder may try it out. Rego Burger Port Elizabeth Cozy Mk 4 #139