A

avi8tor50

Well Known Member
While installling my aileron pushrods I noticed a small hole in the rod bearing ends that attach the pushrod to the aileron bracket. Is there supposed to be a safety wire here and if so how have folks done it. Can't find any mention of a safety wire in the plans.

Peter Katz
9A QB
 
Peter,
I assume the hole you ask about is in the shank of the rod end. That is your "check" hole, and it is very important. The hole allows you to be sure that you have enough threads engaged when you screw the rod end onto the threaded pushrod end. The pushrod end must screw in far enough to BLOCK the hole in the rod end shank. After installation and adjustment, poke a wire in the hole. If it isn't blocked, the installation is unsafe.

Dan Horton
 
Dan is right. The hole is for checking thread engagement. No grease, no safety wire.
 
hole

Is this hole in the big tubes or only on the little bearings ?
I just ordered new big tubes because I think I cut them too short and didn't feel like I had enough threads screwed in.. let me know..


Danny..
 
That's a handy feature. I've noticed the holes before, but didn't know what they were for.

The check hole is only on the female bearing ends. The big tubes use male bearing ends.
 
how much

godspeed said:
Is this hole in the big tubes or only on the little bearings ?
I just ordered new big tubes because I think I cut them too short and didn't feel like I had enough threads screwed in.. let me know..


Danny..
Click to expand...
how much to short? you can get longer threaded rod ends, i would call vans on this one unless your off by an inch or more. and the hole is for safety wire......to see if its on far enough .

these are like the ones i ordered from spruce thay are a bit pricey but were direct replacements for the p/n called out in the plans. CHECK YOUR P/N's FIRST.SPECIFICATIONS: Outer Member: Aircraft Quality Steel, Cadmium Plated. Ball: SAE 52100 Steel. Inserts: Naval Bronze

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FL34-14 ROD END BEARINGS FL34-14M $40.00
F347-14 HEIM MAGNAFLX BEARING F347-14M $66.75
F34-16 HEIM F34-16M MAGFLX BEARING $68.75
F35-14 HEIM ROD END BEARING F35-14M $27.90
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F & HF Series Female Threaded

Heim

View more details
M34-14M HEIM M34-14M MAGNAFLX BEARING $21.30
MD35-14 HEIM R/E BEARING MD35-14M $31.20
MD36-16M HEIM ROD END BEARING MD36-16M $29.50
M44-14 HEIM M44-14M MAGNAFLUX BEARING $30.30
More...
 
Last edited:
too short

Mine looked like they would have made it if they were 1/4 longer :( vans said
the threads should be screwed in the tubes atleast the same amount as they are thick, about 1/3 minimum , about were I was , so I am going to cut my new tubes a little longer.. I want mine screwed in atleast 2/3rds on both ends, half is not good enough for me.. call me foolish but I don't want to
take any chances on the control's all I can say is don't cut the tubes till your doing the rigging, I didn't wait and regret it.. tubes are 30 bucks each I think, the end cones I don't remember, but should be less than 150.00 with shipping but I have not recieved them yet.. so I can't say for sure..


Danny..
 
While we're on the subject of rod end installation, consider a few common sins.

Something I spot all the time is a rod end installed between two ears on a bellcrank without clamping the ball. All relative motion should be between the surface of the ball and its housing. If you don't clamp the ball, relative motion will be between the bore of the ball and the bolt. Wrong; the bolt should be a clamp, not an axle.

Worse is the guy who clamps the ball by tightening the bolt until he bends the bellcrank ears inward. Shame, shame.....

If the ball doesn't fully fill the space between the bellcrank ears, you must install washers or machined spacers between the flat faces of the ball and the ears. Tightening the bolt now clamps the ball without bending the ears.

It pays to be fussy about everything you do with pushrods and rod end bearings. A control disconnect will probably kill you.

Sketch below

Dan Horton

 
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