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Lynn Erickson

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Everything posted by Lynn Erickson

  1. Marc, mentioned a proven and tested system gear system not the one you are thinking about?
  2. thanks Marc, you just saved me a lot of typing. it sounds like you want a wider stance on the gear then stock, if that is your reason to do all this engineering and work I have to say it is a waste of time and money as you will not find a more stable plane on its gear then the cozy 3 and Marc, you mentioned a proven and tested retract system? or was that a proven but not fully tested or a tested but not fully proven system?
  3. when you say Grove gear struts you mean the bent aluminum fixed gear legs?if so why would it attach to the spar?
  4. we also have an SS spacer between the bearings that is .015" smaller then the bore in the casting between the bearing recesses, so even if the bearing was to fail the gear would still pivot but with some play. the bearings are still holding up even after breaking a nose fork and loosing the nose wheel. my fork and fork pivot are now made of billet 7075 alum. the stock long ez fork has been known to break even on some light long ez's.
  5. Sorry Skiing comes before airplanes. i will have to check on the bearing numbers I used. and the engineering was done by a retired Space shuttle engineer and he calc'd the loads and spec'd the bearings for me. and I guess he was right as they seem to work just fine. he said the bearing could take the load and the 5/16" bolt would shear before the bearing would break but the ng 30 would be the first thing to go if the loading was exceeded. he said the bolt and bearing has about ten times the strength of the NG 30
  6. the long ez main gear axle is at WL -22" the bottom is at WL +.9 so about 23 ". depending on the size tires used, the plans size tires are about 11.5" in diameter. so 23" + 5.75 for half the tire = 28.75"
  7. the load on these bearings are not that high. taper roller will work but are big overkill I weighed the taper rollers that wilhemson uses and they are almost a pound compared to the ball bearings which weigh about the same as a quarter. the reason to change is that the bushings get worn and you get wobble on the nose gear strut and this has been known to cause wheel shimmy. The bushings do work , for awhile, the small ball bearing seem to be better as I have used them for 400 hours with out any sign of wear changing the bushings to another bearing is not worth doing if you are going to add pounds to the aircraft.
  8. they do work but the ball bearings are simpler and do not have to be adjusted for preload the ball bearing have built in preload and are a lot lighter in weight. the ones I used are 5/16" id single row sealed ball bearings.
  9. If you do build these I would suggest that you do away with the bushings and use ball bearings as I did or a tapered roller bearing like the Wilhelmson units
  10. the best belts for the cozy are the ones sold by ACS. http://www.aircraftspruce.com/catalog/appages/seatbelt5.php They are designed to work in our cockpits the lap belt adjustments are at the buckles and pull out from the center. this is best because there is little room to have a buckle and a separate adjuster. if the adjuster is on the side it gets caught in the cushion and is very hard to readjust. the shoulder straps tighten by pulling down and have a release strap that is pulled up to release. reasonable price and they work perfect for our planes, and no need to re invent the seat belt
  11. is this a complete flying plane or a project?
  12. it is phenolic micro balloons, it is slightly lighter then glass balloons. it was used on some of the first Ezs but because of the price is not used by most builders. does sand easier but not that much easier to make the extreme price difference worth it.
  13. Multicolour Australia191 Park Street, South Melbourne 3205, Victoria, Australia 613-9690-0898 multicolour@bigpond.com
  14. Did they change the definition of sarcasm? even I can't see any sarcasm in his statement. what word tipped you off to the sarcasm? was it the words "Good point" or was it the word " thanks"
  15. They use that cheap, pull only, lawn mower cable. too many have mowed a lawn with their aircraft using those cables. and they are made for a front mounted engine.
  16. the chewing gum is easy and the disposal requires you to climb during this procedure.
  17. Go with the mechanical back up almost every time I have seen a problem with the nose lift it is something electrical. water in the electrical or motor and the mechanical will still work. mechanical gives you more piece of mind. back up batteries are a pain they only seem to be dead when you need them. I use a dual battery system because then your back up battery is always used and stays in good shape and either one can power the plane by itself if need be.
  18. Why do you think that because it is stronger as a fabric it will be stronger when used with a matrix. that chart is giving you breaking strength of the fabric and does not relate directly to the strength of a composite structure that uses this fabric. the weave is completely different and that is only one property that will effect the strength of a composite structure. you are comparing apples and oranges and saying one is better then the other. but better, how is the question?
  19. The Cozy III gear is a Long ez strut. no difference
  20. the first coat is rolled on and scrubbed into the surface to fill the pin holes. second coat is rolled on smooth and a little thicker to fill the sanding scratches and check for missed pin holes. the first two coats are sanded with 120 grit just to remove the tops of the high spots that the roller left. the third is sprayed on and then sanded to a smooth true surface finish ready for the paint primer. the first two coats do the same thing as the raw epoxy does, it fills the pin holes but also does add some filler on the surface and is much easier to sand then epoxy. rolling on the primer does not build up as much primer as you can when you spray the primer on.
  21. The center of the prop is higher then the wing on most of the canards. there are a lot of factors involved in engineering the correct position. the thrust centerline is also at an angle to the centerline of the aircraft
  22. The gear box is not a V drive it is a straight through box used on front engine/ stern drive boats. and they do not make an aircraft gear box but make them for the E Racer on special order. the cost of the gear box and a all aluminum auto engine will cost more then an aircraft engine before you are all done. there are a few that were built and maybe a few that will fly with the mid- engine/ gearbox but it was not all that successful. even the designer Shirl Dickey was going to change his prototype to an aircraft engine. there are a few others that had mid-engines but they have been converted to engines behind the firewall. With the engine behind the seat you have a lot of noise and heat to deal with. with the engine behind the firewall the area behind the seat becomes a big baggage compartment and all the noise and heat is behind the firewall where it belongs. this configuration makes a great two person traveling aircraft.
  23. be very careful substituting clothes. there are many more thing to consider then it is stronger. its not is it stronger but how is it stronger that counts. there are many factors in choosing the right cloth and unless you are a composite engineer you should stick to the plans cloth. besides the 7725 is only $6.75 from ACS
  24. 135 resin can be used with the slow hardener without post cure the only spar cap that needs the thread removed per plans is the roncz canard. its very easy to remove, after wetting out each ply, you cut the thread in the middle of the length, grab the outboard end and pull each cut strand outboard. the opposite half of wet out layup will hold the ply in place while you pull out the strand. after it is pulled you squeeze it back down from the center, outboard in both directions.
  25. when you do large layups you mix it in small batches so a 3 hour gel time is more then enough. the original Safetypoxy used to build the cozy IV only had a 2 hour gel time and it worked fine.
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