Cleaning, priming & re-skinning elevator spar

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flyingredyeti
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Joined: Sat Jun 20, 2015 10:27 am

Cleaning, priming & re-skinning elevator spar

Post by flyingredyeti »

New topic for the ongoing restoration of '26C. In addressing some corrosion on the elevator torque tube I discovered sufficient corrosion in the rivets (heads spin off when drilled), to warrant opening the elevators entirely, clean prime & re-skin.
While I knew this was a project getting started, I hadn't considered how to actually clean out the inner channel of the spars. I've seen this task referenced by a few on here, so would like to ask for any recommendations that may be available.

Currently, my plan is to use a die-grinder with a red rolock pad, and plenty of water, to slow work my way around the inside of the channel, after which the priming would be done from the front and back of the spar.

Thanks, again.

-Joshua
First time aircraft owner: '26C A gleaming Cessna 170B with 180 horsepower: the perfect mechanical bird.
flyingredyeti
Posts: 108
Joined: Sat Jun 20, 2015 10:27 am

Re: Cleaning, priming & re-skinning elevator spar

Post by flyingredyeti »

Well, turns out I can get my fingers in far enough with a red scotch pad. Still not sure how to clean the webbing.
First time aircraft owner: '26C A gleaming Cessna 170B with 180 horsepower: the perfect mechanical bird.
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johneeb
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Re: Cleaning, priming & re-skinning elevator spar

Post by johneeb »

Joshua,
Can you, and have you considered, using Aluma-prep and a brush?
John E. Barrett
aka. Johneb

Sent from my "Cray Super Computer"
flyingredyeti
Posts: 108
Joined: Sat Jun 20, 2015 10:27 am

Re: Cleaning, priming & re-skinning elevator spar

Post by flyingredyeti »

I've never used a chemical cleaning process, only mechanical, so I've never used this product. However, I just spent about 5 minutes researching Alumiprep 33 and its application process. I'm sold, especially at 19.95/qt from spruce. Thanks John!

I'll have to keep scrubbing the superficial grime by hand- but just discovered I can clean the webbing pretty well through the lightening holes. Yeah, I could definitely use a brush.
First time aircraft owner: '26C A gleaming Cessna 170B with 180 horsepower: the perfect mechanical bird.
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GAHorn
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Re: Cleaning, priming & re-skinning elevator spar

Post by GAHorn »

I have found “bottle” type brushes handy…. sometimes known as toilet “loop” brushes… cut one side and straighten it out… OR>.. one of these:
https://www.sciplus.com/extra-large-bot ... CFEALw_wcB
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flyingredyeti
Posts: 108
Joined: Sat Jun 20, 2015 10:27 am

Re: Cleaning, priming & re-skinning elevator spar

Post by flyingredyeti »

Good idea George. I got into this project yesterday and pretty quickly realized I wasn't properly equipped. I had no more nylon brushes left, only one pad of scotch-brite, and a meager sandpaper selection. Still, in about 4 hours I was able to complete the bulk of the cleaning on the spar, although some work on the webbing remains. A hardware store run is in order.
First time aircraft owner: '26C A gleaming Cessna 170B with 180 horsepower: the perfect mechanical bird.
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