The Cessna 120-140 Association Forum

That's the official name for the ball in the instrument panel that the control yoke tube goes thru.

What type lube is best for the wooden ball and socket? Mine had a caked on black paste that seems to have some graphite in it. It was definitely not doing any lubricating!

This probably has been discussed, but I couldn't figure out how to define it for a search that resulted with posts.

Thanks.

Steve A H

I use LPS#2... sparingly. That's worked well for me.

I use a silicone spray. Apply to my finger tips and spread it on the yoke tube. Really works well and doesn't create a build-up
of gunk on the tube. Use it on the primer plunger also. It won't attack the o-rings.

Larry Surratt
C-140 1946
89011
26R

It's phenolic. There used to be a Teflon replacement part. It was available from Wag-Aero. STC SA666NW. I can't find it any longer.

Thanks for the replies.

I have a can of LPF-2, I'll give that a try. I'm sure silicone would work nicely too.

Thanks for the correction on the ball material, John. It looks just like a hard wood grain on the outside, but it can be seen that it is phenolic in the tube hole.

The 170 folks were buying Delrin® Acetal Resin balls from McMaster-Carr and having them bored, but I don't have a way to get one bored. Univair has the part for $185! Mine aren't sloppy, just were gunked up so they wouldn't move in the socket.

Here's the McMaster-Carr site. Part number is 9614K39.

https://www.mcmaster.com/standard%20plastic%20balls/

Steve A H

FWIW, @ Ebay: Item # 264552689277. $ 0.99 each, 4 available (I'm not the seller).
Mac

Hi, Mac!

Thanks for the Ebay find. The seller says the I.D. is 1 inch. The ones in our planes have aprox. 3/4 inch I.D. Mine are .780...probably a little oversized due to 70 years of wear! The control wheel shaft is .750.

Steve A H

His measurements may be approx guess(?)...in any event, they fit mine perfectly/same size as my old ones (were in 1946). FWIW -- I'm not selling anything . Mac

Steve, you asked about a lubricant that works. I have found that the windshield cleaning spray Clear View works for me if I moisten a rag with it and rub it onto the yoke shaft. It takes several applications of this over a series of flights to get things limbered up nicely.

viewtopic.php?f=8&t=671

I've made many of them, they work great.

BTW, I use silicon spray to lube the yoke shaft.