Date: Sun, 26 Feb 95 22:52:56 EST Subject: Re: Sanding info Ron; Glad we could finally connect, and that you're receiving mailing list mail. >Sorry about the finger. I have often wondered if I had to experience all the >pain I endured while building my bird, at one time, would I do it?, I bled >all over it many times. Thanks. I built a Q2 about 12-14 years ago, and I don't think I ever did anything so stupid that I required stitches (like now), but I remember continually cutting myself on the fiberglass, banging myself on the tables and anything else around, and contorting myself in great pain into bizarre positions and shapes. I loved it, and I'm doing it again. Pain is a strange thing; after it stops, you can't really remember it anymore. You remember the IDEA of the pain, but not the pain itself. Anyway, thanks for the sympathy. Since we haven't conversed before, how far along are you (or are you already flying)? Eric didn't tell me anything except that you wanted to be added to the list. >.................. A hint for your finishing. Make some long sanding >boards of various lengths with progressively finer paper on them. I had a set >of three, 6 foot long boards for my wings. You can get sand p on rolls as is >used in floor finishers to glue onto them. I used 1/8" felt under the paper >for cushioning. They will cut fast and even without the dips. I used Alpha >and micro for fill, put it on thick, like frosting a cake. as I added layers >of fill, I put a few drops of food coloring into the micro so I could easilly >see when I was getting into the last layer and would not damage the structure >underneath. Before you finish, you will develop an aversion to sandpaper that >will last a lifetime! I've used 3 foot sanding blocks before, but never anything as long as six feet. I'll have to try it out. Why the AlphaPoxy? I'm using 2427 for the structure. Does the food coloring do anything to the properties of the epoxy (good idea, either way.)? I don't mind the sanding so much - it's the DUST I can't stand! Good talking to you! -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Fri, 7 Apr 1995 16:19:14 +1000 Date: Fri, 7 Apr 1995 16:13:48 +0200 From: parkyn@citr.uq.oz.au (Nick Parkyn) Subject: Filling and finishing composite structures The following suggestions may be useful and are based on my experience: 1) Separate layups of multiple plies - each ply that is added accentuates the bumps that already exist. Light sanding between layups can help reduce the final bumps or one application of knitted fabric "multi-ply" (biaxial / triaxial) produces the same bumps as single ply (this is used on the Velocity wings). 2) Two type of epoxy resins are available: o the laminating resins which we use to build composite laminates for the airplane o Saturating epoxies which are used for saturating timber when building epoxy saturated timber boats (eg. WEST System Resin, System Three Resin). While saturating epoxies must not be used for the laminates (we use those approved by Nat!) they are the best resins for use when mixing filler, because they are softer making the filler easier to sand. These resins are also cheaper! The other good products are the ready mixed fillers like Microlight from Gougeon Brother (WEST SYSTEM). 3) Most of what you put on, you sand off! If you put on a significant amount to filler you will be sanding and filling trying to chase the right profiles. More care and accuracy in the building stages pays off. All you should need to do is fill the weave!!! 4) Assuming few very small imperfections (weave fill required) filling can be done in two stages. o Fill with epoxy filler to fill weave and imperfections - then sand o If you are using high build epoxy paint primer you can add white micro to the primer to thicken it (test your brand first) and squeegee it on. (it is really is easy to sand the primer). MOST IMPORTANT YOU MUST SAND FILLER OR PRIMER WITHIN A DAY OF PUTTING IT ON OR IT CURES TOO HARD TO SAND EASILY - SO PLAN CAREFULLY. WHEN SANDING THE ONLY WAY IS TO USE A LONG BOARD ("TORTURE BOARD"!!) WITH SAND PAPER BONDED TO IT, OR YOU CREATE BUMPS. AIR POWERED OR ELECTRIC RANDOM ORBITAL SANDERS CAN BE USED FOR SANDING AT PRIMER STAGE, BUT NOT FOR INITIAL FILLER FAIRING. ; Fri, 7 Apr 1995 11:06:54 -0400 Date: Fri, 7 Apr 95 10:04:45 CDT From: qtdalls!ken%qtdalls@uunet.uu.net (Ken Reiter) Subject: Re: Filling and finishing composite structures I just wanted to added to Nick's Filling and sanding message. I have been using the Alpha-poxy mixed with white micro for filling. Is cures in about 7 hours and is easy to sand and work. One of the things that I stumbled across was the use of white micro mixed in with the primer. I am using the System Three water based paint. The paint system is not perfect ( alot of it is me) ; but, so far I would use it again! The true test will be how well it holds up. Back to the story, I mix about 1/3 - 1/5 micro to primer and hand brush it on. Usually, I apply two to three coats with about 3 hours between the coats. It sands very nice with 3M 120 wet ( no dust just water ). After sanding, I spray the straight primer - 2 coats. Then sand with 3M 320 wet. Then on with the color coat, sand that with 3M 600 wet and then the clear. The long board is the best way to sand to remove bumps. Remember to use the 45 degree sanding technique. Also, remember sanding is the WORST part of the whole project. But if you it to sanding you CAN SEE BRIGHT light at the end of the tunnel! Ken Date: Wed, 31 May 95 15:39:58 PDT From: "Michael Antares" Subject: Detail sander Just thought I would pass on for those of you who haven't as yet discovered it. I just purchased a Ryobi detail sander (it is the one with the small triangular plate on it). With 40 grit paper it does wonders in preparing glass for taping in a hurry (plus a lot of other tasks) and is small enough to get into really tight corners. I'm just sorry I waited so long to try it. Michael Antares Software/Hardware Systems Engineering mantares@crl.com Santa Rosa, California From: Lee Devlin Subject: Fiberglass dust reaction? Date: Fri, 16 Jun 95 8:51:42 MDT I was noticing lately that my fingers have been experiencing what I think is a fiberglass reaction. I've been very careful to use ply-9 and gloves every time I do a layup and not to let any uncured epoxy touch my skin but I haven't been so careful when sanding around fiberglass with cured epoxy. It could also be a reaction to the powder in the latex gloves which I understand can be an allergen. But for some reason, I feel that it has to do with the little bits of fiberglass that land on my skin while sanding. So far, it has only affected my fingers up to the second joint. There a lot of very small bumps that have a sort of numb feeling to them. They didn't appear immediately, but about two days after I did some sanding/layups. I first noticed it about a week ago and I've been building for about 3 months. It's worse on the sides and backs of my fingers than on the fronts. I'll be on vacation for the next few weeks so hopefully my fingers will return to normal before I work on the plane again. Needless to say, I intend to change my work habits and will wear the gloves while sanding. I also intend to use the butyl gloves and wear the cotton liners under them and the latex gloves over them. Has anyone else experienced a reaction like this to fiberglass dust? Lee Devlin From: Marc J. Zeitlin Subject: Fiberglass dust reaction? (fwd) Date: Fri, 16 Jun 95 11:03:16 EDT Lee D. writes: >..... There a lot of very small bumps that have a sort of numb feeling >to them. They didn't appear immediately, but about two days after I did >some sanding/layups. I first noticed it about a week ago and I've been >building for about 3 months. It's worse on the sides and backs of my >fingers than on the fronts. >Has anyone else experienced a reaction like this to fiberglass dust? Yes. The little itchy bumps are the sign of fiberglass dust particles embedded in the skin. I get it if I'm not careful to wear long sleeve shirts when I sand, especially when I'm rubbing hard on a large flat surface and my arm is in contact with the cured layup. I got a major reaction on both arms when sanding the fuselage exterior with a short sleeve shirt on. My fingers don't seem to be affected. I just did a 5 hour layup of the canard shear web on Wednesday night. On Thursday, I noticed a 1" x 1" patch on my left forearm which was slightly swollen and itchy, but smooth and with no bumps or spots. This is the epoxy allergic reaction. I must have touched the layup just below the gloves and above the long sleeve. Oh, well. At least I know that: 1) I'm still allergic to epoxy 2) If I wear the butyl gloves and a mask, I'm O.K. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Fri, 16 Jun 1995 11:09:23 -0400 From: SidLloyd@aol.com Subject: Re: Fiberglass dust reaction? In a message dated 95-06-16 10:56:56 EDT, leed@hpgrla.gr.hp.com writes: >It could also be a reaction to the powder in the latex gloves which I >understand can be an allergen. Try vinyl gloves. You can get them from Direct Safety @ 1-800-528-7405. Sid Date: Mon, 19 Jun 1995 09:43:37 -0400 From: NBalog@aol.com Subject: Re: Fiberglass dust reaction? (fwd) This may not be allergy, but irritation. The difference being: exposure to cinnamon will make your skin red an itch, while exposure to poison ivy will make it red, itch, peel, and occasionally cause systemic effects. It's wise not to tempt fate and develop an allergy though; keeping exposure down helps, but if you're really allergic, inhalation and long-term exposure to the dust will keep reminding you to build a metal plane Date: 5 Oct 1995 12:46:59 -0500 From: "Bill Schertz" Subject: Re: Fiberglass Dust "Scott Mandel" Reply to: RE>Fiberglass Dust Scott, et.al I haven't started on fiberglass fabrication, but have done a lot of woodworking, where some of the dusts actually can be toxic. the thing that worked best for me was designing a dust collector that removes dust from the air before it gets a chance to settle on me. The device that works best in my shop is a special sanding table that I made. It cost me 1 sheet (4x8) of plywood, and a 2'x4' piece of perforated masonite. The basic idea was from a magazine called woodsmith, and I can get issue number for those interested. Being cheap, I modified the plans enough to limit my purchaes to the one sheet of plywood, but the idea is the same. It basically is a rectangular box, with an old furnace blower (free) in it that blows (out) of the box at the end, a double layer of furnace filters (20"x20") covers the top of the box, and the perforated masonite forms a cover over the top of the filters. The top sanding surface is 2'x4', I sand my work with it sitting on this bench, with the blower running. The dust is sucked --immediately-- DOWN into the holes in the top, and never flys around the shop. With some of the big parts like a Cozy wing, etc. the whole thing could not fit on the bench, but you could have the part being sanded over the downward flowing airstream. When working with my belt sander, I just set the belt sander on this bench, and the dust off the end of the belt just disappears as fast as it is formed. Bill Schertz -------------------------------------- Date: 10/5/95 12:20 PM From: Scott Mandel Subject: Time: 12:08 PM OFFICE MEMO Fiberglass Dust Date: 10/5/95 I recently got a very bad fiberglass dust rash. I consulted my doctor and he said to try Aveeno, Corn Starch, or Baking Soda in a cool bath. It worked really well to get rid of the fiberglass in my skin. I also used some over the counter anti-itch stuff. If anyone else has found other aids let me know. I'm really sensitive and get the glass rash even through my clothes. Has anyone had any success keeping dust from getting in your skin. ------------------ RFC822 Header Follows ------------------ Date: 5 Oct 1995 12:12:29 -0600 From: "Scott Mandel" Subject: Fiberglass Dust Date: 5 Oct 1995 12:12:29 -0600 From: "Scott Mandel" Subject: Fiberglass Dust Subject: Time: 12:08 PM OFFICE MEMO Fiberglass Dust Date: 10/5/95 I recently got a very bad fiberglass dust rash. I consulted my doctor and he said to try Aveeno, Corn Starch, or Baking Soda in a cool bath. It worked really well to get rid of the fiberglass in my skin. I also used some over the counter anti-itch stuff. If anyone else has found other aids let me know. I'm really sensitive and get the glass rash even through my clothes. Has anyone had any success keeping dust from getting in your skin. Date: Sat, 7 Oct 1995 14:13:13 -0400 From: StetsonE@aol.com Subject: Re: Fiberglass Dust On 10/5 Stott Mandel wrote: >I recently got a very bad fiberglass dust rash. I consulted my doctor >and he said to try Aveeno, Corn Starch, or Baking Soda in a cool bath. >It worked really well to get rid of the fiberglass in my skin. I can't help you with skin reactions. I've never had any skin reaction whatsoever from "E" glass dust, however "S" glass (gear struts) will make me itch. I think I'm just thick skinned - at least that's what my wife tells me..... But since we're on the subject of glass dust, the purpose of this reply is to remind everyone the importance of dust masks when sanding fiberglass. I ignored it for the first part of my project, and often got cold/flu like symptoms. It turns out the glass dust irritates your nose/throat/lungs, and will definitely make you sick. Use a good dust mask. Don't bother with the cheap disposable surgical type masks. They usually don't fit well, and for those who have to wear glasses (like me), they often cause your spectacles to fog up. I picked up a good mask from Sears. It has a black rubber face portion and holds a round cleanable/disposable filter of about 3" diameter. I just remove the filter and vacuum it off on a daily basis. It's well made and very comfortable. About $20.00. Stet Elliott stetsone@aol.com Perpetual Long-EZ builder Date: Wed, 18 Oct 1995 00:44:00 -0400 From: KSPREUER@aol.com Subject: Builder Hint-Urethane Foam Carving CH 13, 18, 21... I just discovered a neat tool for rough shapping the 2 lb urethane foam. This would work very well on the Nose, Strake L.E. and the Canopy frame. I'm working on the Canopy. I microed in the foam blocks per plans. I then used a rasp to carve the foam down close to the template shape at FS. 41, 50, 60, and 70. I then took a wire brush and stroked it across the foam. It provides a good deal of control but removes foam pretty rapidly. I wire brushed until the contour between the template points was eye ball close on the fat side and then finished in the conventional manner.