Yoke Control Shafts Cleanup

[Buckeyechuck]

I’m in the process of doing the 500 hour inspection for the yoke control shafts on our ‘62 C model. We actually removed the shafts to properly perform the penetrant test and not make a mess. While they are out we would really like to get them cleaned up. Problem is I cannot find a shop around here that can turn them around in a reasonable time. Plane is getting a new GFC500 installed. Has anyone considered other options for restoring these shafts. 

[Buckeyechuck]

Ok, let me clarify a bit. These control rods “proper term is column in the parts book” were originally chrome plated. Most of the chrome is gone. The rods look like crap and are not as smooth in function as they should be. I am constantly lubing them. Turn around time to rechrome is a very long time. I’m considering a different process such as cerrakote, a ceramic coating which is a similar thin coating, self lubricating, and high wear.  This product is advertised as routinely used for aerospace use. I wanted to get some other ideas from the forum before discussing with my A&P/IA. 

[Igor_U]

I think some A&P/IA might object legality of the ceramic coating on on a certified plane... 

I'd like to hear form others about thins.

[StevenL757]

1 hour ago, Igor_U said:

I think some A&P/IA might object legality of the ceramic coating on on a certified plane... 

For what reason(s) ?

[Igor_U]

3 hours ago, StevenL757 said:

For what reason(s) ?

Good question that I couldn't find good answer in a past.

I would think concern is there's a no approved OEM manufactured or FAA process. Many claim, as an example, FAA and manufactures do not approve chrome plating of the propeller spinner as it can alter metallurgy of the aluminum; those are always polished or painted. 

Funny, the shafts on my (and OP's) plane are chrome plated and so is the retractable step on my F. But, I'm certain couple of IAs I worked with in a past would frown if I wanted to use "non-approved" finish on my plan's control system.

 

I'd be certainly interested to hear other opinions; I'm sure those would vary like we saw it in the past.  

[Prior owner]

Chroming process can also cause embrittlement, I believe…I’m not sure that you can just send them out for chroming like an old bumper…but I could be wrong. I’d do plenty of research on this before doing so- chroming includes removal of metal prior,to chroming, and these shafts are very thin walled to begin with.

 

Other coating processes would likely include media blasting which, once again, may affect the thin walled tubes negatively. Be careful!

[Buckeyechuck]

3 hours ago, PilotCoyote said:

Other coating processes would likely include media blasting which, once again, may affect the thin walled tubes negatively

Agree, rechrome has numerous potential drawbacks. Local shops are mostly hard chrome industrial processes. Not what is needed here. Local finish chrome shop turnaround was 10 weeks and caused numerous concerns with prep. They don’t understand what they are working on. That’s why I’m reaching out to MS. Ceramic is a spray on and bake process. Does require blasting. Some medias don’t cut metal but may not properly prep surface. I’m still investigating.  I’m  also looking at a DIY nickel process. 

[Prior owner]

Are new shafts available? If so, at 60 years old, it is not unreasonable that it is time to replace them. Our fleet is very old, and at this point in time, one must expect that maintenance costs are going to become quite high to keep them airworthy.

[Buckeyechuck]

I’m not concerned about condition, PT’d the entire shaft. No defects.  

[47U]

1 hour ago, PilotCoyote said:

Are new shafts available?

I’m pretty sure @Bob R received factory new yoke shafts a few months ago for his E.  He updated to the J-style yokes and retired the yoke shaft AD at the same time.  I’m not sure what the lead time was for the factory to produce them, but they are making parts.

[Bob R]

3 hours ago, 47U said:

I’m pretty sure @Bob R received factory new yoke shafts a few months ago for his E.  He updated to the J-style yokes and retired the yoke shaft AD at the same time.  I’m not sure what the lead time was for the factory to produce them, but they are making parts.

Lasar had one but the pilot side lead time was 8-12 weeks. It took about 15 weeks to receive it. Have to say that after actually seeing the difference in shaft thickness, I was happy I retired this AD.

[Buckeyechuck]

how many AMU’s is a new one?

[tim417]

@Buckeyechuck

I called an MSC in Arizona and they looked it up for me. Factory charges near $6,000 for the upgraded 201 style yokes with shafts, new. 

[Hank]

There are ways to safely blast them clean without damage. Look for someone who uses dry ice blast or ground walnut shells. Both perform well, one requires no cleanup afterwards. 

[Buckeyechuck]

1 hour ago, Hank said:

There are ways to safely blast them clean without damage. Look for someone who uses dry ice blast or ground walnut shells. Both perform well, one requires no cleanup afterwards. 

Yes I’m familiar we use dry ice blasting in the mill I have worked in to clean large motors. Also familiar with walnut shell and corn cob blasting. 
 

6 g’s for new shafts and yokes is a bit rich for me. 
 

At this point I’m going to clean up what I have and put them back in the airplane. 

[Bob R]

On 5/19/2022 at 5:08 PM, Buckeyechuck said:

how many AMU’s is a new one?

$1000 each or so for the shafts. Found a nice pair of J control wheels for $450.

[tim417]

@Bob R

Yes, if one finds the right shafts for his vintage used, he can get them maybe even for less than $1000 a pair. Control wheels are about $1000 a pair as well unless you are patient and a little lucky. 

After buying a pair of nice 201 control wheels for $1000, I came upon a set of wheels with the shafts I needed for $750 or so for everything. I ended up selling the original pair I got. Wheels are now off for leather wrap.