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Sandng aluminum

PostPosted: Wed Jan 18, 2023 7:36 pm
by karmarepair
It's a thing, and I'm a Believer. I had a time getting the twenty years old protective film off of my flaps and ailerons and even after heat and scrape I still had a residue of re-solidified plastic and adhesive that solvents would not touch.
Influenced by DCSupershine "the More you send the less you Polish", with fear and trembling I tried some 320 grit with my Harbor freight cordless DA sander.

I can't believe how well it worked. I also tried cleaning it up with some 600. Wow.

My intention all along was to keep my airplane bare aluminum but not necessarily polished. My current intention is to finish the tops of the flaps and ailerons 320-400-600-800 grit before first flight.

In the future, I will try polishing use tools and materials from Harbor freight, but for now, better is the enemy of good enough.


https://eaabuilderslog.org/?blprojentry ... tcat=&sid=

Re: Sandng aluminum

PostPosted: Thu Jan 19, 2023 11:43 am
by dbdevkc
So heat gun and peel didn't work? I would be interested in other's opinions on that much sanding.

Re: Sandng aluminum

PostPosted: Thu Jan 19, 2023 6:03 pm
by karmarepair
dbdevkc wrote:So heat gun and peel didn't work?

Oh, it worked, and worked better than anything else, it just didn't get it all. And this is not a problem too many builders are going to experience. The film currently used is much easier to get off. Mine was the older opaque white film, 20 years old. I'll post some pictures when I get a chance.

Re: Sandng aluminum

PostPosted: Thu Jan 19, 2023 7:22 pm
by dbdevkc
I had that on some of the pieces I received in my kit.

Re: Sandng aluminum

PostPosted: Fri Jan 20, 2023 9:36 am
by GordonTurner
Be conscious of the amount of material you are removing. .025 only allows .0025 removal before part should be replaced. That isn’t very much.

All the best, Gordon

Re: Sandng aluminum

PostPosted: Fri Jan 20, 2023 3:28 pm
by dbdevkc
That was my thought. The normal polishing we do does not remove much material at all, but sanding will.

Re: Sandng aluminum

PostPosted: Fri Jan 20, 2023 3:55 pm
by Bryan Cotton
Naphthalene is my go-to solvent for adhesives.

Re: Sandng aluminum

PostPosted: Fri Jan 20, 2023 10:15 pm
by karmarepair
Bryan Cotton wrote:Naphthalene is my go-to solvent for adhesives.

Umm, Napthalene is a solid. http://en.wikipedia.org/wiki/Naphthalene
Did you mean Naptha? http://en.wikipedia.org/wiki/Naphtha

Re: Sandng aluminum

PostPosted: Fri Jan 20, 2023 10:21 pm
by karmarepair
GordonTurner wrote:Be conscious of the amount of material you are removing. .025 only allows .0025 removal before part should be replaced. That isn’t very much.

That accounts for the Fear And Trembling I mentioned earlier.

320 grit sandpaper has particles averaging 0.0014". I'm only removing the adhesive residue, and a little more, so although I haven't miked any of my workpieces, I'm not worried. Much.

Re: Sandng aluminum

PostPosted: Fri Jan 20, 2023 10:50 pm
by Bryan Cotton
karmarepair wrote:
Bryan Cotton wrote:Naphthalene is my go-to solvent for adhesives.

Umm, Napthalene is a solid. http://en.wikipedia.org/wiki/Naphthalene
Did you mean Naptha? http://en.wikipedia.org/wiki/Naphtha

Yes! Thanks for the correction. Works great on old tape residue, or any adhesive thing.