Perfecting Alignment of Axel Nut to Cotter Key Hole ...

[HFS]

If (for whatever reason) the cotter key hole in your axle & nut do not line up to your liking, you can easily solve that problem in one of two ways -

By machining the face of the nut - Since the thread pitch of the axle nut is 16 tpi, it means that for every "flat" advancement, there will be .01041" of movement toward the wheel spacer (or bearing) ((1/16)/6). So, if, for example, you are a half a "flat" tight, just face off .01041/2 = .0052", and you should be good to go.

By adding shims - To move the nut away from the wheel spacer (or bearing). Using the example above, you need a ~ .0052 spacer to make the holes line up. McMaster-Carr (Aviation Division) P/N 92022A347 Stainless Steel Ring Shim - 1.25 i.d. x 1.75 o.d. x .005, that will do the job within .0002 - close enough for me ...

HFS

 

[rocketbob]

Slotting the holes on a mill works well too Dave.

 

[Sam Buchanan]

Another tip is to add another set of holes in the nut (on different flats) which allows a bit of margin for lining up with the axle.

 

[DHeal]

Another tip is to add another set of holes in the nut (on different flats) which allows a bit of margin for lining up with the axle.

As Sam suggests, drill a second cotter pin hole in the axle stub. I drill the second hole 1/2 flat revolution away from the primary hole -- usually located @ 90 degrees from the primary hole). This way you have a 1/2 flat adjustment factor.

 

[RV7A Flyer]

I had one that got just a smidge loose after a hundred hours or so. McMaster sells peelable shims in the right ID/OD, and just a few layers (they're quite thin, don't recall the exact dimensions of each layer) tightened it up nicely.

 

[PCHunt]

I had one that got just a smidge loose after a hundred hours or so. McMaster sells peelable shims in the right ID/OD, and just a few layers (they're quite thin, don't recall the exact dimensions of each layer) tightened it up nicely.

There is so much to learn...... and so little time!

 

[Bavafa]

As Sam suggests, drill a second cotter pin hole in the axle stub. I drill the second hole 1/2 flat revolution away from the primary hole -- usually located @ 90 degrees from the primary hole). This way you have a 1/2 flat adjustment factor.

Why not drill a new hole in the axle, assuming this was an axle that we are working on.

 

[Larry DeCamp]

How loose is loose ? How tight is tight ?

 

[Freemasm]

How loose is loose ? How tight is tight ?

Per the old school A&Ps/IAs; no perceivable axial motion. Wheel should easily turn by hand but a spin by hand should arrest itself in 1/2-3/4 or a turn.

Now, where that tribal knowledge is actually specified? No clue. It did make rudimentary sense to my young brain -> no slop in the bearing/raceway interface and not too tight to add unnecessary friction.

Now I'll await an answer based on OEM releases or Regs from someone here if there is one.