Corrosion R Us

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:: cross posted ::

On a whim, I picked up a spot blaster from HF to see if I could clean up the steel parts on my Quicksilver seat frame and related tubing. While it performed decently so I could get a view of the underlying metal, it really didn’t have the horsepower to clean things up fantastically. But the great news is the condition of the tubing is really good. I scoped the tubes revealing just a little bit of surface corrosion on the inside. As hoped, there is a weep hole in the low point that allowed any excessive moisture to escape.

So instead of spending more money on a bigger sandblasting rig — coupled with my time — I’m going to bring it to a pro shop to get them properly cleaned and refinished. After that I’ll probably flow some rust converter through the tubes just for peace of mind. Probably unnecessary, though.

More positive progress in my book! Looking into the Ospho technique. I’m not familiar with that process.

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BBerson

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Ospho should remove that light rust. The phosphoric acid will chemically remove light rust if you spray it or brush it on and let it work 10 minutes. Then wash it off with water and dry it with a towel. If that doesn’t do a second coat might. If you let it dry it converts the rust to iron phosphate. If you want to paint bare steel then wash it off and paint. I use Ospho for almost everything. It cleans rust in the shower 5 times better than anything else.
 

fly2kads

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I have used Ospho for a few jobs on the restoration of my 1966 VW Beetle. I treated the underside of the package tray (above the transmission), cleaned up a replacement glove box door, and some other assorted smaller parts. I have followed the package directions, and it has worked very well for me. Ordinary primers have adhered very well to the "toothy" surface left by the Ospho.
 

BBerson

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I use twisted wire wheel in the hand grinder for big jobs. It is super fast and takes off rust and paint. Wear thick leather gloves, eye protection and don’t let it catch and kick back or at least be ready and hold it firm. Or pulse the trigger in tight spots of the cluster. I don’t recommend powdercoat. Multiple coats of regular oil based tractor paint will last. Even spray can.
It burnishes, so not quite as good as sandblast. So an almost dry wipe of Ospho might add tooth.
 
Joined
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Messages
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Location
Germantown, WI USA
I use twisted wire wheel in the hand grinder for big jobs. It is super fast and takes off rust and paint. Wear thick leather gloves, eye protection and don’t let it catch and kick back or at least be ready and hold it firm. Or pulse the trigger in tight spots of the cluster. I don’t recommend powdercoat. Multiple coats of regular oil based tractor paint will last. Even spray can.
It burnishes, so not quite as good as sandblast. So an almost dry wipe of Ospho might add tooth.
I did grab some cans of tractor paint recently. Sounds like a winner when used with a wire wheel and/or ospho. Another person suggested a wire wheel as well. I tried with an abrasive nylon wheel. Even the coarse one didn’t really make a dent. Sounds like I need more RPM/horsepower like an angle grinder.
 

Dan Thomas

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I did grab some cans of tractor paint recently. Sounds like a winner when used with a wire wheel and/or ospho. Another person suggested a wire wheel as well. I tried with an abrasive nylon wheel. Even the coarse one didn’t really make a dent. Sounds like I need more RPM/horsepower like an angle grinder.
That tubing might be powder-coated. It's tough stuff.
 

Larry650

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At my age I hate hard work. Or at least the pain in my hands after the hard work is done, so I have found a paint and rust removal service here in Phoenix. These people will remove paint and/or rust right down to bare metal in large vats of chemicals with no damage at all to the base metal. The advantage of liquid paint and rust dissolvers is that they get inside the tubing thru weep holes and clean the inside as well as the out. They also offer sandblasting with fine grit media. I just had them strip and derust a bicycle frame and fork. Both came back the next day squeaky clean, right down to bare metal, for $40. Perfectly done, I might add. Figuring the cost of paint removing chemicals, paper towels, sandpaper, my time and then arthritis painkillers, that's a great deal.
Xpress Metal Stripping
 

Dan Thomas

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Sep 17, 2008
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7,230
At my age I hate hard work. Or at least the pain in my hands after the hard work is done, so I have found a paint and rust removal service here in Phoenix. These people will remove paint and/or rust right down to bare metal in large vats of chemicals with no damage at all to the base metal. The advantage of liquid paint and rust dissolvers is that they get inside the tubing thru weep holes and clean the inside as well as the out. They also offer sandblasting with fine grit media. I just had them strip and derust a bicycle frame and fork. Both came back the next day squeaky clean, right down to bare metal, for $40. Perfectly done, I might add. Figuring the cost of paint removing chemicals, paper towels, sandpaper, my time and then arthritis painkillers, that's a great deal.
Xpress Metal Stripping
One must make sure they're using strippers that don't cause hydrogen embrittlement of spring-steel stuff like gear legs.
 
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:: cross posted :;

@BBerson and another builder friend suggested I try a twisted wire wheel on a grinder within a half hour of one another. Since two rights can’t be wrong, Menards received sixteen more of my hard-earned dollars and I came home with a spinning wheel of wonder. It did great work in short order as described! And was a heck of a lot less messy. Thanks for the direction, Bill! Now let’s give ‘er a wipe down and a coat of black tractor paint.

I’ll see if I can find Ospho to do the wipe down to catch any corrosion in the crannies before shooting it. Best place to find it? Napa?

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Hawk81A

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Ospho is available at Home Depot, Lowes, and other stores like that - even hardware stores. Definite second on the warning about commercial strippers and their chemicals. Some chemical strippers, like muratic acid eat the rust like nobody's business, but WEAKEN the metal. FWIW, I'm working on a go-kart project for my nephew. Kid brother said someone gave it to them. BAD rust. ad to cut a lot out and weld in new steel. At least it doesn't fly.
I was looking at your earlier posts with the bolts and the holes they came out of. Would have been nice, and stronger (all around) if they'd have welded in steel tube bushings instead of just drilling holes. Of course other than extra expense, it would also have been extra weight - one more case where ultralight rules can add danger. Dennis
 

BBerson

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Ospho is neat stuff. I was having some frustration with welds that were rusty. I sanded best I could but rust remained and foamed. I tested some Ospho and it cleaned deep where I couldn’t sand. Welded nice.
 
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