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Control Stick, part 5

scottly

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Ok, here's the final version. Previously, I made a bearing collar that used a needle bearing set but have decided not to use that version....This version is using a phenolic block/bearing.
Earlier, I mentioned that I wanted to cage the phenolic because although it is very strong, I felt a bit safer it the block were caged. Wanting to keep it simple and light, I caged it so that it would weld to the fuse the same way the plans-built bushing does.
I used some 3/8 x .065 tubing and some 1" x .125 strap I had lying around. The 3/8" tubing is used as a dowel when boring the phenolic blocks to fit the torque tube.
The 3/8 tubing is actually slightly larger diameter, so I machined the outside of the tubing so that I had a lip for the strap to bump up against after drilling 3/8" holes in the upper strap. I set the height of the lip so that the tubing was inset about .25 at the bottom of the block. I then welded the strap to the tubing on the top. I reamed the inside of the tubing to .250. I drilled the bottom strap to .250. This will allow me to insert 1/4" bolts and secure block halves:




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The upper strap and tubing is then welded to the fuse cross members just like the plans version.


The thrust collars will be welded to the torque tube when I weld the assembly into the fuse at a later date. The phenolic blocks are wider than the strap, but I do not think this will be an issue....as previously stated, I believe the blocks are strong enough to support themselves, but the cage is just an added margin of safety in my brain. :) Here's what it looks like now:


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Page 11, detail 15 had to be made longer to accomodate the lower position of the torque tube due to the thicker material of the phenolic.


I would like to know how many degrees of travel the sticks should have...the only reference I see is that the stick should have enough travel to allow for 30deg of elevator travel, but I'd like to know how much stick travel I should have, just to be sure.


Here's my final:


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Just to mention: For the stick-to-stick push rod, I used an AN24-17 clevis bolt and AN320-4 nut, both being low profile so that they would easily clear the torque tube....just in case you might have that problem.


Well, that's the last post from me for a while....I have some building to do. All fuse fittings are done, control sticks are done, pedals are done, wing control parts are done, drag/antidrag wires done,horizontal tail pieces are done, ribs are done, center section parts are done, ailerons are almost done....Next comes leading edges, aileron completion, wing assembly, then start welding fuse. Edited by: scottly
 

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