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  1. Cloud Dancer


    Over kill for an Avid Flyer or Kitfox but worthy of mention is the solution used to fix the tail on Draco. Link here: https://youtu.be/j2WKyra8HBc

    A small air cylinder with adjustable flow ports on the intake and exhaust could be used to dampen the Avid or Kitfox wheel similar to how the Draco was tamed. We had many hydraulic cylinder designs that used this idea to control flow under various load conditions. Those smaller air cylinders are made of aluminum and are very light and the flow restriction idea works for air just as well as hydraulic fluid. The gas block on an AR-15 is another example of a port being used to control gas flow rate. Many applications use needle valves to make the flow rate adjustable.

  2. nlappos


    My high speed shimmy stopped when I tightened up the pivot nut enough to damp the wheel pivot, but at that happy place where the TW still castored and allowed me to turn. Took a little experimenting.

  3. nlappos


    Some thoughts about that diesel heater:

    1) The heat value makes no sense, at 0.24 Liters per hour max diesel flow, that would be right at 8000 btus. (diesel has 139,000 btu's per gallon, .24 liters is .06 gallons per hour. akflyer confirms this flow when he saw 1 gallon every 24 hours, that is about .05 gal per hour) . The claimed 8000 watts is about 27,000 btus.  Even so, I would bet the 8000 btus it really gives out is nice heat.

    2) Putting heater, a flame source, in the cabin is near suicide, anything goes wrong and its toast.

    3) Putting it right outside (like akflyer's belly pod), with a firewall between it and the cabin would be pretty safe.

    I have the Avid "stock" heater funnel off the left radiator and it works well down to about 25F (all I've seen so far). If the water temp drops to 145 or 150, the heater falls off too. As a result I block my belly rad off (at 35 deg takeoff, I have it half blocked). Most important was lifting the top cowl and blocking all the area behind the firewall up to the windshield off so the drafts almost stop. I also sealed the door leading edges with stick-on door seal, works well.

    1 person likes this
  4. marksires


    Jenki, not the same as split lock or spring.  both of those are to keep the fastener from becoming loose.  Belleville washers are to keep the connection from coming loose, or to keep constant, predictable pressure on a connection.  One use of them is when fastening a wooden propeller, so as the wood expands and contracts with humidity the connection to the hub stays tight.

    Mark

     

  5. akflyer


    I will be shaving a lot of weight off it as there is no real need for the long pipe runs etc.  Also don't need the muffler on it, just a straight pipe going out.  I think the 2KW would be more than enough as these things really do put out some good heat!  I could even mount it in a "belly pod" so its all self contained under the plane then just pipe in the heat under the seat.

     

  6. Buckchop


    Well -14 here last few days and think im gettin to b a whimp sometimes about the cold, So decided was time to widen the doors on the Blackfox #0021.  So got a 4x8 sheet of lexan and started peelin right side door apart to change lexan and bend up a new center bar. Looks like ill get 1.75" on each side at ur shoulder, elbow, knee.  My Bluefox has this done but only 1.5" on each side. Sure makes a lot of difference on the older narrow body Kitfox and probably just as well on the earlie Avid. Ill post more pic as i get them done. 

    image.jpg

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    1 person likes this
  7. wypaul


    KSpiit lock washers are not the sameSpring Washer as bellville washers.  Here are some pictures h each.  JImChukImage result for belleville washers

    Spiit lock washers are not the sameSpring Washer as bellville washers.  Here are some pictures of each.  JImChukImage result for belleville washers

    Thought this showed up the first time I posted it.  :-)  JImChuk

     

    this showed up the first time I posted it.  :-)  JImChuk

    Hey Jim that second picture looks more like nord-locks than Belleville washers.:) Probably just the picture, here is a different one.

    https://en.m.wikipedia.org/wiki/File:Belleville_washer.jpg

  8. Jenki


    Thank you very much. Better to have more answers than not know what is exactly going on.

    I need to check it, better say, I will ask manufacturer as I am reaching 200 hours for inspection. I will ask for both, check of caster angle and U-strap settings (resistive damping).

    It will be the last mandatory inspection (2 years since manufacture date) so they will do complete check. I didn't fly Bristell since 9th September till 5th December now (nearly 3 months) due to starter clutch repair (I am using old ROTAX 912) so I missed good or at least suitable weather here to fly to manufacture. Till the inspection it is still under warranty period and I need to be ready to bring all findings to solve.

  9. 1avidflyer


    Spiit lock washers are not the sameSpring Washer as bellville washers.  Here are some pictures of each.  JImChukImage result for belleville washers

    Thought this showed up the first time I posted it.  :-)  JImChuk

  10. marcusofcotton


    Jenki,

    Belleville washers are washers that are not flat, they are cupped, and if not made of spring steel, have some spring to them so they keep pressure on the bolt/nut when they are torqued down correctly.  The amount of pressure can be varied by changing how much torque is applied to the bolt.

    Mark

     

     

    Jenki,

    Belleville washers are washers that are not flat, they are cupped, and if not made of spring steel, have some spring to them so they keep pressure on the bolt/nut when they are torqued down correctly.  The amount of pressure can be varied by changing how much torque is applied to the bolt.

    Mark

     

    Oh, thank you, we call this spring washer, split lock washer ... now I understand

    No Jenki, not a split lock washer, these are belleville washers. Nested stack increases the pressure available, inverted stack increases the range of operation. Nested and inverted increase both. They are not designed to be tightened down flat. Do an internet search on them.

    https://www.mcmaster.com/belleville-disc-springs

    P.S. I missed that others had already answered... had an image added too but it didn't make it.

     

     

  11. Turbo


    No, Belleville spring and split lockwasher are two different things.  Belleville spring, if laid on a flat surface, is raised on the inside relative to the outside.  It's like a shallow cone, with elevation varying with radius only.  When compressed, the outer edge is in tension, and the inner edge is in compression.  It's a nonlinear "softening" spring; spring rate decreases with deflection towards flat.

  12. Cloud Dancer


    They hung them upside down because of too little offset on the Rotax gearbox and so they could be cowled like a conventional airplane. If the engine was upright the oil would accumulate in the bottom of the engine because the fuel/oil charge enters through the side of the crankcase and not the head. 

    The gearbox can be mounted in four different positions. Too bad nobody makes an intake manifold to fit  a down draft carburetor on the Rotax engines. Then it could be mounted on it's side with the intake on the top and the exhaust on the bottom. Any fuel mix dripping through when it's not running would drop out the exhaust ports if it happened to make it past the rotary valve.

    2 people like this
  13. Turbo


    Just completed the mod to correctly relocate my EGT probes.  Again, thanks to all, especially Vance.  I'm keen to fly it to test it out.  Looking at my carbs, it appears the previous owner knew what he was doing, setting it up slightly rich on the part-throttle needle, hanging 'em high, and with the next size larger (than Rotax recommends) needle jets.  It will be interesting to see what results.  With no cabin heat, though, fear of the dreaded freezerburn keeps me on the ground for now.  Plus, the days are so darn short, and my bird doesn't live at the airport.  Temporal overhead for launch is a bitch.

  14. 1avidflyer


    Not really just then.  just taxied him around in it.  The friend of mine that passed away a year ago did fly with me  a few times though, and he was about 6' 1" and weighed about 240.  We filled up the space for sure.  Maybe that's why I like the idea of widening the fuselage.  JImChuk

    1 person likes this
  15. PW_SD


    Hello Gents,

    I have a pair of Avid STOL wings for sale here in San Diego.  

    Age and full condition unknown, they will require restoration, including rib-tail flaperon attachments.  Flaperons not included.

    Asking $500 for the pair and motivated to clear some space!  I have jury struts available as well, separately.

    Email or PM me with any questions.  Will be posting to Barnstormers soon.

    Thanks!

    Phil

     

     

    Avid STOL Wings.JPG

  16. Jenki


    Problem with not enough "resistive damping" could be caused by missing "silentblock" or sort of flexible material inside U-strap in my case I think.

  17. Jenki


    Jenki,

    Belleville washers are washers that are not flat, they are cupped, and if not made of spring steel, have some spring to them so they keep pressure on the bolt/nut when they are torqued down correctly.  The amount of pressure can be varied by changing how much torque is applied to the bolt.

    Mark

     

    Jenki,

    Belleville washers are washers that are not flat, they are cupped, and if not made of spring steel, have some spring to them so they keep pressure on the bolt/nut when they are torqued down correctly.  The amount of pressure can be varied by changing how much torque is applied to the bolt.

    Mark

     

    Oh, thank you, we call this spring washer, split lock washer ... now I understand

  18. Chris Bolkan


    That's my friend Jeromie.

    He was building a carbon fiber plane. It consisted of a carbon fiber fuselage. Murphy Rebel wings I think, aTitan tornado full flying empanage and a kitfox7 firewall forward. He got a lot of the way done but abandon the project and ended up just buying a clipped wing piper. So he is parting everything out. 

    He has the complete KF7 FWF setup minus engine. This exhaust is part of that setup. i was hoping I could use it on my Fat Avid, but it won't work.

    Anyway he now has a lot of random stuff for sale and what doesn't sell will be thrown away.

  19. Chris Bolkan


    That's my friend Jeromie.

    He was building a carbon fiber plane. It consisted of a carbon fiber fuselage. Murphy Rebel wings I think, aTitan tornado full flying empanage and a kitfox7 firewall forward. He got a lot of the way done but abandon the project and ended up just buying a clipped wing piper. So he is parting everything out. 

    He has the complete KF7 FWF setup minus engine. This exhaust is part of that setup. i was hoping I could use it on my Fat Avid, but it won't work.

    Anyway he now has a lot of random stuff for sale and what doesn't sell will be thrown away.

  20. Chris Bolkan


    Guys, you are going to chase shimmy all day long re-arching springs to change castor angle in hopes of eliminating it. The only real solution is enough adding enough friction in the back and forth movement of the wheel (resistive damping) to critically dampen the resonance. Shimmy is a resonance. Just sayin.....

    The trick is adding enough friction in the back and forth movement of the wheel to kill the shimmy but still be able to overpower the friction with steering springs..

    That's why some of the really big tailwheels have gone away from steering springs altogether, because it takes so much friction that steering doesn't really work anymore and you have to steer with differential breaking.