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Aileron push rod assembly bushings

PostPosted: Sun Jul 26, 2020 1:06 pm
by Rofomoto
On my final stages here. Last thing is my aileron push tube attachment. Is the 5/16 od bushing Supposed to turn with the push rod assembly tube snx-c03-2? Or is the bushing stationary and the push rod assembly tube turn on the outside of the bushing ? Thanx billy

Re: Aileron push rod assembly bushings

PostPosted: Sun Jul 26, 2020 6:11 pm
by sonex892.
Rofomoto wrote:On my final stages here. Last thing is my aileron push tube attachment. Is the 5/16 od bushing Supposed to turn with the push rod assembly tube snx-c03-2? Or is the bushing stationary and the push rod assembly tube turn on the outside of the bushing ? Thanx billy


Hi Billy.
There are 2 different bushing setups at play with the bearings at the pivot bellcrank.
The pivot as shown in the photo the bronze is fixed to the bellcrank support bracket and should not rotate. The bellcrank, bolt and steel bushings are bolted together and move as one. The movement, rotation is between the inside of the bronze and the outside of the steel bush.
With the pushrods. The bushing is fixed to the bellcrank and the movement, rotation is between the outside of the bronze and the inside of the hole in the tang on the pushrod. I hope that makes sense.
Steve
Sonex 892
Image

Re: Aileron push rod assembly bushings

PostPosted: Sun Jul 26, 2020 6:40 pm
by Rofomoto
So the powder coating is to be removed from the 5/16” hole in aileron control tube correct? The bushing in the control rod should be able to rotate.

Re: Aileron push rod assembly bushings

PostPosted: Sun Jul 26, 2020 8:30 pm
by sonex892.
Rofomoto wrote:So the powder coating is to be removed from the 5/16” hole in aileron control tube correct? The bushing in the control rod should be able to rotate.

Thats correct

Re: Aileron push rod assembly bushings

PostPosted: Sun Jul 26, 2020 9:04 pm
by NWade
And please note something that I re-discovered on the plans just yesterday:

A 3/8" long bushing is called out on the plans, but if you measure the 1/2-scale detail drawing you'll see that the drawings show it as only 1/4" long! This is so that the narrow end of the flanged bearing is flush with the bronze washer that sits between the aileron pushrod and the bellcrank.

I'd manually shaved my bushings down to roughly this length and assembled the system, but in recent checks (as I near first flight) I noticed that mine were still a few hundredths of an inch too long and I didn't like the slop that left in the connection with the bellcrank so I've ordered some1/4" long flanged bearings from McMaster-Carr that should be the exact right specs. I'll post an update as soon as I've gotten them and checked the fit!

--Noel
Sonex #1339

Re: Aileron push rod assembly bushings

PostPosted: Sun Jul 26, 2020 9:52 pm
by Rofomoto
sonex892. wrote:
Rofomoto wrote:So the powder coating is to be removed from the 5/16” hole in aileron control tube correct? The bushing in the control rod should be able to rotate.

Thats correct


Thanx!!

Re: Aileron push rod assembly bushings

PostPosted: Thu Jul 30, 2020 12:42 pm
by NWade
NWade wrote:A 3/8" long bushing is called out on the plans, but if you measure the 1/2-scale detail drawing you'll see that the drawings show it as only 1/4" long! This is so that the narrow end of the flanged bearing is flush with the bronze washer that sits between the aileron pushrod and the bellcrank.

I'd manually shaved my bushings down to roughly this length and assembled the system, but in recent checks (as I near first flight) I noticed that mine were still a few hundredths of an inch too long and I didn't like the slop that left in the connection with the bellcrank so I've ordered some1/4" long flanged bearings from McMaster-Carr that should be the exact right specs. I'll post an update as soon as I've gotten them and checked the fit!


Just a quick update to say that I have received and installed the 1/4" long flanged bearings from McMaster-Carr and they are a perfect fit!

If you are working on SNX-W02 and don't want to deal with cutting or sanding the specified Symmco bushing down to length, the McMaster-Carr part seems to be a great alternative.

--Noel
Sonex #1339