Light surface rust problem.

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FritzW

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Jan 30, 2011
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Las Cruces, NM
Hi All,

My unfinished fuselage is showing some light rust. It's at the stage that I can still wipe it off with a paper towel and maybe a little scotch bright work.

Any thoughts on the best way to deal with this?

Cleaning it up and wiping it down with something like WD-40 sounds like a good idea but whatever I put on now I'll have to clean off sometime in the next month or two so I can paint it.

Thanks
Fritz
 

steveair2

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Jun 1, 2007
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990
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Dallas Texas
If it's finished welded, I'd epoxy primer it. You can do it in sections. My future method will be to finish weld and epoxy primer in sections as I progress from firewall to tail post.
This will save much time and effort. If you need to add any tabs or such, just burn off the primer weld and re primer.
 

cheapracer

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Sep 8, 2013
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Australian
One method is to wipe your frame down with a diesel soaked rag for temp storage. Later use some brake cleaner to clean the spot you want to weld.
 

Brian Clayton

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Dec 7, 2012
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Ivey, Ga and Centerville,Tn
ospho works great. Its not really a coating, so you can clean up any areas to weld tabs with a scotchbrite pad quick. Heavy oil coating are hard to clean back off before painting and you get nasty everytime you touch it.
Ospho reacts with concrete and aluminum though, so beware. I use a spray bottle (like a old windex bottle) at work on chassis I am working on. Doesnt take much, about like using windex.
 

Brian Clayton

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Lowes sells it under "metal prep" in the plumbing section last I saw. Green liquid in a clear quart bottle, JONESCO brand or something like that. By the drano and such last I bought there. Some places have it in the paint section under either "metal prep" or "Ospho". Just look at the label, should say phosphoric acid. And it doesnt "do" anything when you spray/wipe it onto steel/rust, takes a few hours usually for it to turn black. It will turn black on rust, and just darken the CM tube coating a little. Just have to get it damp, not dripping. If its dripping wet, it leaves a heavy whitish residue that is a pain to clean out of joints, aside from sandblasting. On restos, I take several gallons and saturate all the body seams with a pump up sprayer before I sand blast, that way all the "internal" rust is treated too, not to mention the deep pits blasting may not get. Its some great stuff.
 

FritzW

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Las Cruces, NM
I just picked up a gallon of Ospho at a local hardware store, I'm heading out to the garage to give it a try.
 

Pops

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Jan 1, 2013
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USA.
I have a very large supple of 4130 tubing and flat plate that I bought from Dillsburg about 12 years ago when Charley told me that in the future the 4130 was coming from China. Something like 30-40 sticks each of the more common sizes and lots of flat plate in different thickness. To protect the steel from rust, I spray with Sprayon LU-767. Made for storage of machine tools and dies. No rust anywhere IF you do not touch it with bare hands. Always handle while wearing gloves. Easy to wipe off and weld. I always epoxy prime after a light sandblasting with play sand from Lowes box store. Dan
 

BBerson

Light Plane Philosopher
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Dec 16, 2007
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Port Townsend WA
The Ospho will actually remove some pretty heavy rust if you apply it multiple times and scrub while wet. Don't let it dry while scrubbing, then when done just wipe most of it off with a dry rag, then when the film is dry it is ready to paint.
I don't like to let a thick coat dry, it leaves a whitish dust.
 
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