Elevator bellcrank securing

[svyolo]

The tube that the elevator bell crank pivots on needs to be secured somehow. I can't find anything on the plans, and an old version of the kit builder manual mentions a cotter pin. I would think a single AN3 bolt through one of the two stand off tubes would suffice.

I can't find any other reference.

[Nev]

If this is the forward bellcrank, I’ve put a split pin through each side.

600263AF-9316-4B33-8C3E-270FACE1190A.jpeg

[svyolo]

I ended up just thru bolting the left standoff.

[Battson]

I put a split pin through the left standoff.

If you orient the pin vertically, then there's no risk of it dropping out.

[James]

Yep - A bit like what Nev did:

1) Get the EW positioning of the bellcrank right, because the bolt head at the bottom of this bellcrank can hit the flap wire.
2) Make up spacers from aluminium tube (I also had washers against the bellcrank as "wear surfaces"). Nev's picture doesn't have spacers, but maybe the kits have been improved since mine.
3) Slide in pivot tube flush with LH standoff
4) Drill a single hole 3/32 through the LH standoff, and through one half of the tube. You don't have to go out the other side of the tube.
5) Put the head of a split pin inside the tube, and bend the legs around the outside like Nev has done.
6) Cut RH end of tube flush with standoff (to save weight)
7) Remove tube, and put two notches on the RH end of this tube, to allow you to get a pin punch or screwdriver in there and rotate the tube to line up with the hole again.

There was actually a bit of resistance to getting the tube in and out, so I could never imagine it falling out, even without a splitpin.

Note that, with Nev's approach, the tube is free to rotate, but with mine, it's locked to the standoffs (as it would be with an AN3 bolt). But the Bolt hole would be much bigger.

MY AIRCRAFT ISN'T ACTUALLY FLYING YET, SO TAKE MY ADVICE WITH CAUTION! :-)

Hope that helps,

James

[svyolo]

The kits have changed a bit. No spacers required (or any extra space for). The tube supplied with the kit didn't have enough extra to drill outside the standoffs. I did with a bolt what Battson did with a pin, I drilled nearly vertically and inserted from above. If the nut drops off, gravity keeps it in place. I think that is a bit of an old school rule of thumb. Insert bolts head up, or head into the slipstream, if able. Although, like everything else, sometimes you can't.

[James]

Yeah, I drilled through the standoff as well, pinning the tube to the standoff.

I'm glad the kits have been changed with regard to the bellcrank placement - this could have been a real "gotcha" moment, if I hadn't thought about the flap cable clearance before drilling.

- James