Yoke and Yoke Shaft Refinishing

How to keep the Cessna 170 flying and airworthy.

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brian.olson
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Joined: Mon Aug 14, 2017 12:04 pm

Re: Yoke and Yoke Shaft Refinishing

Post by brian.olson »

I spent some time yesterday cleaning up the yoke bearing brackets and fine-tune sanding the Deltrin bearings (balls). The brackets were coated in some quite resistant grime that I attacked first with solvent (the bracket on the left of the photo has actually been thoroughly soaked and cleaned with solvent) and then finished with a Dremel. All four came out pristine.
IMG_E6895.JPG
I used sandpaper wrapped around a wooden dowel to sand the inside of each Delrin ball, first starting at 220-grit and finishing with 1200-grit to give a nice, smooth and form-fitting dimension.

Today, I reinstalled everything - first with the Delrin bearings and the brackets, and then the new universal joints (which arrived via USPS mid-afternoon). You can see the old vs. new joints in the following photo. I'll note that there is zero excess play with the new universal joints and the yokes are rock-solid, yet move easily in all directions.
IMG_6910.JPG
Before wrapping up for the day, I pulled the throttle cable knob off and shot a photo of the completed project (at least this project). I'll strip the knob tomorrow evening and once the rains stop and the humidity drops I'll be able to paint with primer, the red color coat, and finally a few coats of clear coat to protect everything.
IMG_E6911.JPG
Very happy with the outcome and I feel much safer knowing the universal joints are new.
Brian
1950 170A
N5762C s/n 19716
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GAHorn
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Re: Yoke and Yoke Shaft Refinishing

Post by GAHorn »

Very nice job, Brian!
Yes, the universal joints are certainly important and the originals are all over 60 years old now. I pulled the ones out of my ‘62 Skyhawk and they were covered in powdered red-rust and had loose pins (with no protective rubber hose to prevent their leaving). There are stories of these things failing...so a little preventive mx is a good idea for all to consider. Expensive (IMO at $300...they were about half that not long ago...and may be less expensive elsewhere or if generic 1/2” ones are found), but not hard to replace, and available from Aircraft Spruce and others.

But just imagine what it would be like for one to fail or jam inflight. At least check them and see if the pins are tight and they are lubricated and free of excess play. IMO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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rnealon1
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Re: Yoke and Yoke Shaft Refinishing

Post by rnealon1 »

After discussion with Brian and George, I decided to re-do our yokes, which were chipped. While in Annual I removed both yokes and shafts at the universal joint (not easy to reach the right one!) and had a local shop powder coat them and ordered the vinyl lettering decals from stickylife.com (I thought I had uploaded the artwork correctly but made a call just in case and they straightened it out).
Old 1.jpg
Old 2.jpg
New 1.jpg
New Logo.jpg
Pretty happy with the results, will see once they are reinstalled.

Thanks for the help and advice!

Bob
Bob Nealon

Southbury, CT
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brian.olson
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Re: Yoke and Yoke Shaft Refinishing

Post by brian.olson »

Looks amazing!
Brian
1950 170A
N5762C s/n 19716
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rnealon1
Posts: 219
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Re: Yoke and Yoke Shaft Refinishing

Post by rnealon1 »

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20230914_152845.jpg (78.06 KiB) Viewed 9951 times
Bob Nealon

Southbury, CT
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GAHorn
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Re: Yoke and Yoke Shaft Refinishing

Post by GAHorn »

Beautiful Work!
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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rnealon1
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Joined: Wed Sep 19, 2018 7:28 pm

Re: Yoke and Yoke Shaft Refinishing

Post by rnealon1 »

Thanks for all the help and suggestions!

Bob
Bob Nealon

Southbury, CT
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mmcmillan2
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Re: Yoke and Yoke Shaft Refinishing

Post by mmcmillan2 »

Looks awesome! Now go clean up them rudder pedals!
170B owner, KCFD, CFI(I), ATP Multi
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rnealon1
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Re: Yoke and Yoke Shaft Refinishing

Post by rnealon1 »

Oh, if only that were the last item on the list!
Bob Nealon

Southbury, CT
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