[jmartinez443]

So I'm fitting my flap weldment on my 8 and it sits pretty snugly in the delrin blocks. How snug should this be?

If it should swing fairly freely, what have others done? Sand down the ends of the weldment? Grease the blocks? If so, what kind of grease is delrin compatible with?

Thanks for your input.

 

[DGlaeser]

Pretty snug is OK . . .

I had the same question on my 7A. The answer I got was - if you can move it, it's OK, and it will loosen with time. I don't think any lubricant is necessary or helpful - it all gets squeezed out and the delrin doesn't absorb anything.
I even had to chamfer the holes on the end pieces, due to interference with the welds to the arms. Furthermore, the location of the center block (don't know if the 8 has this) didnt align with the unpainted spot on the tube, so I had to sand off the powder coating in the correct location.

 

[C-GRVT]

shim it

if the block is one that you have to cut to fit over the tube, the hole ends up smaller by the thickness of the cutting blade - if this results in a too tight fit on the tube, you can shim the block to restore the original thickness.
Bill Brooks
Ottawa Canada
RV-6A not yet flying

 

[Guy Prevost]

It should be pretty snug. If you can get the tube in the hole (without resorting to extreme measures), it's not too tight. You don't want the flaps to be rattling around.

 

[jmartinez443]

Sounds like a plan

It should be pretty snug. If you can get the tube in the hole (without resorting to extreme measures), it's not too tight. You don't want the flaps to be rattling around.

Yea I can get the weldment in ok with a little pressure. I don't have to resort to a BFH or anything. And the weldment does move with slight resistance.

So I guess I'll call it good. I was just wondering if the movement needed to be bearing-smooth.

Regarding chamfering the ends of the block: the though crossed my mind. There's like a human-hair's separation between the weldment and the inside front edge of the blocks when the arms swing down. I think I'll shave them a smidgen.

Thanks all for your input.