Date: Sat, 11 Jan 1997 14:33:08 -0800 From: marcna Organization: ratdog Subject: COZY: New Electric Pitch Trim System I'm just about to install a new electric trim system that was introduced at Copper State last year. The system used a spring plunger, similar to the one Vance developed. The difference is in the motor that powers the system. The Alex Strong Trim System uses a Black and Decker screwdriver motor with the cluch set to the 1 setting. The unit is very easy to install and sells complete for $175.00 Alex is also a member of the Cozy group "Alex Strong " For more information you can email him or visit his web site at: http://www.concentric.net/~Marcna/Alextrim.html Marc Parmelee N425CZ From: Marc J. Zeitlin Subject: COZY: chapter 17: landing brake assy. Date: Wed, 29 Jan 97 10:06:10 EST People; Thanks for all the input on the wires in the control stick! Got another question - think I've answered it, but want to check with others. As one of the Luddites :-) using the stock non-electric landing brake system, the first line in the plans for landing brake installation tells me to attach CZLB-15 to CZLB-10. This is the round rear pulley with the tang, and the upper bracket that also attaches to the springs. There's a tapped hole in the pulley, and the plans say to attach the bracket to it with an AN3-6A bolt, a couple of washers, and a nut. I _ASSUME_ (knowing the old saying about assuming making an ass out of you and me :-) ) that I'm supposed to put them together like: pulley bracket | | | | | | | | || || |-| | | | | || || |--| -|-|--|-|------------| | AN3-6A bolt -|-|--|-|------------| | |-| | | | | || || |--| nut | | | | || || | | | | washers with the bolt going through the bracket bushing (through hole) and threaded into the pulley (tapped hole). The nut would then just be used as a locknut. The problem is that when I do this, that there seems to be _way_ too much slop - the bracket rattles around on the bolt something fierce. I need three or four washers to get rid of the extra space. It seems I should either use an AN3-5A bolt instead of the AN3-6A called for, just add more washers, or I'm misinterpreting the instructions and actually have no idea what I'm doing here :-). Can one of the other anachronists :-) out there straighten me out? Thanks. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Wed, 29 Jan 1997 14:34:48 -0500 (EST) From: Westlande@aol.com Subject: Re: COZY: chapter 17: landing brake assy. In a message dated 1/29/97 3:08:14 PM, marcz@hpwarhw.an.hp.com (Marc J. Zeitlin) wrote: > The nut would then just be used >as a locknut. > >The problem is that when I do this, that there seems to be _way_ too much >slop - the bracket rattles around on the bolt something fierce. I need >three or four washers to get rid of the extra space. It seems I should >either use an AN3-5A bolt instead of the AN3-6A called for, just add more >washers, or I'm misinterpreting the instructions and actually have no >idea what I'm doing here :-). > >Can one of the other anachronists :-) out there straighten me out? >Thanks. > >-- >Marc J. Zeitlin Email: marcz@an.hp.com Marc, I built my own parts from the plans a couple of winters ago. The nut does act as a stop nut, at least that's the way I did it. I can't recall the exact length of the bolt I used, but all that really matters is that the end of the arm that the springs attach to clear the pulley when you open/close the brake. It does not have to be too long to do this. anachronistly yours, Eric From: Marc J. Zeitlin Subject: COZY: chapter 17: Roll trim question Date: Wed, 29 Jan 97 16:26:11 EST People; I've got a question regarding the stock manual roll trim. After connection all the cables from the handle to the RT-2's I find that I've got a hysteresis "dead zone", where motion of the trim handle does _not_ lead to motion of the control sticks. I can move the handle 1/8" to 3/16" to either side of center before the sticks begin to move. Also, whatever the position of the handle (left, right, center), I can move the sticks 5 degrees or so to either side before they will begin to be pulled back by the springs. I've got the requisite 1" of stretch on each of the RT springs. Without any trim connections (springs disconnected) the control system feels very smooth, with almost no drag at all from the delrin (phenolic replacement) bearings and less than 1/2 degree of free play in either stick before the other stick begins to move. The pitch trim system does not exhibit this "dead zone"; i.e. for each minuscule motion of the pitch trim handle, the elevator (and control stick) move a concomitant minuscule amount. Is this only a problem (if it is one) because I don't have the wings on and there are no aerodynamic loads? Do I need to just pull the springs tighter or shorten them? Has anyone else seen this phenomenon? aTdHvAaNnKcSe -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Wed, 29 Jan 97 15:42:00 PST From: Brian DeFord Subject: Re: COZY: chapter 17: Roll trim question People; >I've got a question regarding the stock manual roll trim. After >connection all the cables from the handle to the RT-2's I find that I've >got a hysteresis "dead zone", where motion of the trim handle does _not_ >lead to motion of the control sticks. I can move the handle 1/8" to >3/16" to either side of center before the sticks begin to move. Also, >whatever the position of the handle (left, right, center), I can move the >sticks 5 degrees or so to either side before they will begin to be pulled >back by the springs. >I've got the requisite 1" of stretch on each of the RT springs. Without >any trim connections (springs disconnected) the control system feels very >smooth, with almost no drag at all from the delrin (phenolic replacement) >bearings and less than 1/2 degree of free play in either stick before the >other stick begins to move. The pitch trim system does not exhibit this >"dead zone"; i.e. for each minuscule motion of the pitch trim handle, the >elevator (and control stick) move a concomitant minuscule amount. Marc, I had the same problem. I went to Nat to see if I could get the answer and it appears that the springs he used were not necessarily the ones called out in the plans (He said he used what he had laying around the shop). Anyway the bottom line was that he said to use a spring with enough stiffness to get the job done. I used a spring from Century Spring (purchased at Home Depot) that did a much better job. It is much stiffer, is the correct length and already has the ends coiled for easy attachment. Sorry, but I don't have the part number on hand with me. I'll try to locate it if you are interested. Brian DeFord by SERV05.SLAC.STANFORD.EDU (PMDF V5.1-4 #16063) with SMTP id <01IESIE69GA0002CKD@SERV05.SLAC.STANFORD.EDU> for cozy_builders@hpwarhw.an.hp.com; Wed, 29 Jan 1997 16:26:12 PST Date: Wed, 29 Jan 1997 16:26:13 -0800 From: hrogers@SLAC.Stanford.EDU (Howard Rogers) Subject: Re: COZY: chapter 17: Roll trim question I agree with Brian, Marc. I don't think that there is anything too sacred about the strength of the springs, and it is largely a matter of personal preference, and "feel". On the original Long EZ, Mike Melville expermented with stiffer pitch trim springs, because he liked the idea of additional insurance against breakage when using a trapped compression spring (like the ones you typically find on a tail-wheel). He wrote up his findings for Canard Pusher. He said that some people might not like the more touchy stiffness of the compression springs, and left it up to the discretion of the builder. On the subject of the hysteresis, I think you would probably find, in flight, that the combination of air loads and vibration would probably make it disappear. Try two or three spring-stiffnesses, and pick the one that feels "right" to you, after flying them. Howard Rogers A&P 2005148 Date: Wed, 29 Jan 1997 22:17:47 -0500 From: Mahan Subject: Re: COZY: chapter 17: Roll trim question Howard, I used the compression pitch trim springs on my Long-EZ and they work very well. No complaints. And, yes, I like the idea that one won't let go *bang* and leave me fighting a pitchup or pitch down. Fred in Florida Long-EZ N86LE From: Marc J. Zeitlin Subject: Re: COZY: chapter 17: Roll trim question (fwd) Date: Thu, 30 Jan 97 9:41:06 EST Howard Rogers wrote: >I agree with Brian, Marc. I don't think that there is anything too sacred >about the strength of the springs, and it is largely a matter of personal >preference, and "feel". Agreed. I don't like the hysteresis, though - sort of negates the purpose of the trim system :-). >........ On the subject of the hysteresis, I think you would probably >find, in flight, that the combination of air loads and vibration would >probably make it disappear. Yeah, I kind of hope so, but I was hoping to hear from people who were already flying to see how their roll trim systems were working, and what they did to get the right "feel" (especially if they found hysteresis upon original assembly). >....... Try two or three spring-stiffnesses, and pick >the one that feels "right" to you, after flying them. Well, I took Brian's suggestion, went to Home Depot, and tried three different springs last night. None of them did squat for the hysteresis. I took the torque tubes out, opened up the Delrin bushings a couple of thousanths with some 100 grit, and put them back together. Without springs, the system was even smoother than before, but with them..... still a dead zone. I think what's going on is that the force of the springs causes extra friction at the front bushing, and that stronger springs just causes more friction force. This seems to balance itself out, so that there's always some zone in which the force can't overcome the friction. Maybe I just need to use ball bearings for my front torque tube pivots :-(. So, Brian, if you can find the spring # you used, I'd appreciate hearing it. Thanks - hoping to hear from some of you flyers regarding your systems. -- Marc J. Zeitlin Email: marcz@an.hp.com From: "Charles F. Wolcott" Subject: Re: COZY: chapter 17: Roll trim question (fwd) Date: Thu, 30 Jan 1997 08:02:59 -0800 > > Thanks - hoping to hear from some of you flyers regarding your systems. Hi Marc - I found I had to adjust the spring tensions several times for both the pitch and roll trim. Once you get this tuned to how _you_ like it, I think the stock trim devices work fine. I don't see how you could accurately select springs for the best feel and tension until the bird flies. At least that sort of thing rarely happens to me! : ) I bought a selection of springs (similar lengths, but different ratings) and got pretty good at removal and installation before I was happy. Chuck Wolcott chuckw@qnet.com 175 hrs on Mk4 #154 From: "Krasa, Paul" Subject: Re: COZY: chapter 17: Roll trim question (fwd) Date: Thu, 30 Jan 1997 12:28:51 -0500 Marc writes >Agreed. I don't like the hysteresis, though - sort of negates the >purpose of the trim system :-). >........ On the subject of the hysteresis, I think you would probably >find, in flight, that the combination of air loads and vibration would >probably make it disappear. I have the same situation on my Long EZ, and decided to fly it after looking at flying Long EZs and Cozys in my area and finding that about half of them have the same hysteresis. I have also tried shortening the springs to increase the preload and found it did not make a difference. Paul Krasa Long EZ 214LP !---*---! Date: Thu, 30 Jan 97 14:19:00 PST From: Brian DeFord Subject: COZY: Chapter 17: Roll trim spring used Much deleted... >So, Brian, if you can find the spring # you used, I'd appreciate hearing >it. >Thanks - hoping to hear from some of you flyers regarding your systems. Marc, The part number is C-133 (Century is the maker) and the spec's are 7/17 X 2-1/2 X.047. By the way - I agree with your earlier assessment that the problem is most likely due to the friction of the tube on the front bearing as the spring pulls them together. Although it is a simple system, it has much to be desired IMHO. Brian DeFord Date: Thu, 30 Jan 1997 18:42:58 -0500 (EST) From: CCady@aol.com Subject: Re: COZY: chapter 17: Roll trim question (fwd) If you haven't tried already you might try a close tolerance bolt for the stick pivot. This is something that was in the Canard Pusher way back as a means to eliminate some play in the stick. Cliff In a message dated 97-01-30 09:42:25 EST, you write: << >I agree with Brian, Marc. I don't think that there is anything too sacred >about the strength of the springs, and it is largely a matter of personal >preference, and "feel". Well, I took Brian's suggestion, went to Home Depot, and tried three different springs last night. None of them did squat for the hysteresis. I took the torque tubes out, opened up the Delrin bushings a couple of thousanths with some 100 grit, and put them back together. Without springs, the system was even smoother than before, but with them..... still a dead zone. >> From: Epplin_John_A@hpmail1.90.deere.com Date: Fri, 31 Jan 97 11:29:16 -0600 Subject: COZY: Roll trim related. Does anyone have a roll servo for some form of auto pilot? Where does that connect to the system? Could some such thing be used for a roll trim? I am building an electric pitch trim system with the intention of using it for the auto pilot pitch servo later on. Might not work, but I intend to try it at least. Experimental aircraft? John Epplin Mk4 #467 Date: Thu, 6 Feb 1997 03:24:12 -0500 (EST) From: KSPREUER@aol.com Subject: Re: COZY: Chapter 17: Roll trim spring used In a message dated 97-01-30 19:25:18 EST, you write: << Subj: COZY: Chapter 17: Roll trim spring used Date: 97-01-30 19:25:18 EST From: Brian_DeFord@ccm.ch.intel.com (Brian DeFord) Sender: owner-cozy_builders@hpwarhw.an.hp.com Reply-to: Brian_DeFord@ccm.ch.intel.com (Brian DeFord) To: cozy_builders@hpwarhw.an.hp.com All deleted... I had the hysterisis problem on the three place and have seen it on many Cozy's. The problem is that the trim system puts a large side load on the torque tube resulting in friction in roll. The larger the spring the larger the friction. If you are going to keep this awkward system, the answer is to reduce the friction in the torque tube bearings. I found the best answer is to design a system that does not generate large side loads while it applies a torsion force on the torque tube. I designed a torsion spring that attaches to the forward part of the torque tube forward of the stick. The torsion spring is "grounded" by a lever that is part of the outside winding. (It is concentric to the torque tube). The lever protudes up thru a slot in the arm rest just forward of the stick. I built a bracket there that allows the lever to be set at a range of left - right positions to set the force on the roll stick. The bracket clamps the lever between teflon so it can slide smoothly and be held where set. It adds no noticable friction and has no dead spot. If it breaks there is no unbalanced force. Full stick motion is achievable regardless of the trim position. Date: Mon, 28 Apr 1997 17:36:05 -0400 From: Paul Burkhardt Subject: COZY: Re: cozy chap 17 Maybe I just need to use ball bearings for my front torque tube pivots : I used the system outlined in CSA a while back which uses roler bearings on the front torque tube(against the phenolic block) there are two washers sandwiched outside the bearing. These work great and are cheap If anyone is intrested I'll go dig up the numbers> I believe they are torrington part numbers. Paul Burkhardt From: Marc J. Zeitlin Subject: COZY: Chap. 17 - Landing Brake Damper Date: Mon, 21 Jul 97 15:33:10 EDT People; As promised, here's my report on my attempt to add a damper to the landing brake (manual, not electric) to prevent the handle slamming either up or down and pulling the cable out of the nicopress fitting. I purchased the following parts from McMaster-Carr (908-329-6666): 6521K11 Hydraulic Damper, Extension, 0.24" rod, 2" stroke $12.47 9416K77 Safety Clip for 10mm metal ball socket fitting $ 2.63 9416K71 Metal end fittings for 10mm ball $ 2.50 9416K73 10mm Ball Stud, 5/16"-18 thread (pr.) $ 1.00 The idea here was to attach the damper in such a way that it would be extending either as the handle reached full up position or full down position - this would give me damping at either end of the handle travel. I achieved this by putting the handle in the middle of it's movement range, and marking a point on the perimeter that was the aftmost on it's circumference. I then drilled and tapped the handle (making sure that the hole was far enough in not to interfere with the cable groove) for one of the 10mm ball studs. I needed to shorten the threads on the stud about 1/8" so that it would not hit the center console wall. Next, I drilled and tapped a 1/4" thick by 1.5" square aluminum piece for the other ball stud and mounted it with a couple of AN5 washers to space it out a bit. With the Landing Brake completely installed and working, I snapped the damper onto both ball studs and positioned the aluminum plate on the side of the console directly aft of the centerline of the LB handle. I clamped the aluminum plate to the console side, and while operating the handle slowly, I positioned the plate so that the damper would not reach either it's fully compressed or fully extended position at any time. I then floxed and glassed the plate to the console side with 2 BID. After cure, I drilled and re-tapped the plate hole (some epoxy had gotten in) and then mounted the damper. Handle (in middle position): ## ## (X) marks ## ball stud mount ### on handle (moves) ### with handle #### # # # # -------------| Ball stud mount # X-----| |-X in aluminum plate # # -------------| floxed to console # # Damper inside wall (fixed) #### Cylinder You can see from this sad ASCII picture that as the handle rotates in either direction, the damper will extend (the "X"'s will move apart), and since this is an "extension" damper, it will apply a resistance to the movement and slow down the handle (and brake). It works reasonably well, substantially slowing down the handle if it's just released and would otherwise smack into either end. I've heard of passengers getting their left thighs smacked with the handle - this won't happen in my plane. However, I did a "fatigue" test, and with 4 releases on the extended end (handle up) the fourth smack pulled the cable out of the nicopress fitting on the rear pulley again!!! I don't want to restart the whole nicopress fitting debate, but I had installed and measured (with the nicopress gauge) that fitting, and it met spec. I can only hazard a guess that the shock of hitting the stop is more than the nicopress can handle without the mitigating factor of a thimble. Anyway, I reinstalled the cables with two nicopress fittings in series. I have come to the conclusion that this Landing Brake design is less than optimal, even having sprung from the head of the master Burt. So, what's the upshot of all this? I guess I'd say that this damper installation is a qualified success. For us Luddites who don't use an electric Landing Brake actuator (for our own twisted reasons :-) ) this damper assembly will mitigate (but not eliminate) the shock at either end of the handle motion. It's cheap (<$20), easy (maybe 2-3 hours total, once you know what to do) and kind of cool. It's not the panacea that I was hoping for, but it does help, and it was fun. Ce la vie. -- Marc J. Zeitlin Email: marcz@an.hp.com From: Marc J. Zeitlin Subject: COZY: Ch. 17 - Roll trim and bearings Date: Tue, 2 Sep 97 12:44:16 EDT People; In January I posted a note regarding hysteresis in my roll trim and control sticks. I've finally gotten around to installing a couple of ball bearings to replace the Delrin bearings (to replace the plans called out Phenolic bearings :-) ) that I previously had. I chose some 5/8" ID, 1 3/8" OD, .375" thick sealed ball bearings from Grainger (I think) - they were about $12.75 each, and can be used for both the front and rear bearings in the control system. I used them just in the front. Yes, I know that you can get bearing kits for all four bearings (if not all six) for about $120 or so - I just felt like making my own :-). I made some bearing mounts from Delrin in the machine shop that held the bearings in the same place as the original Delrin bearings and the two large washers - it's almost exactly a drop in replacement for the 1/4" bearings with the two 1/16" washers. One of my torque tubes ended up with some linear play (about 0.010") so I removed the trim lever tube, shortened it a bit, and put one of the washers back in. Voila, no play. Anyway, the whole point of doing this was to remove rotational friction in the system to remove the hysteresis in the trim system. Another qualified success - there's a lot less hysteresis, but it's not completely gone. Since many people are flying with the original system and have this hysteresis (and live with it), I'll just see what happens. I can always swap in other bearings at some other time. This roll trim system is less than optimal from a friction standpoint. The pitch trim system works GREAT - no hysteresis or play at all. Something along the lines of Keith Spreuers roll trim (on the web pages) is functionally better, but I'd like to see something that is center mounted for use by either side of the cockpit. -- Marc J. Zeitlin Email: marcz@an.hp.com From: Gunrider@aol.com Date: Thu, 30 Oct 1997 18:03:43 -0500 (EST) Subject: COZY: SPRINGS & WINDOWS On the landing brake - for cosmetic and exposure reasons I am wondering if anyone succesfully shortened these two springs and moved the bracket lower on the back of the seat back to be out of the way? Bad Idea???:) Anyone considered making the side windows larger for claustrophobic passengers? How well does it work and look? Hugh Farrior Finishing Ch. 17 From: cdenk@ix.netcom.com Date: Thu, 30 Oct 1997 20:13:14 -0600 (CST) Subject: Re: COZY: SPRINGS & WINDOWS Remember to make 2 ply BID covers for the landing brake mechanism and forward of rear armrests. I used cardboard/posterboard & hot glue gun, taped with duct tape for release to make mold. Advantages: 1: Safety, its easy to load the luggage and jam something, or something to roll into a bad spot. 2: Appearance. Covers are held in place with a few 8-32 stainless machine screws. I wouldn't change anything on spring length, the brake linkage is supposed to close if speed is too high.