Stripping powder coat paint from steel tube.

[wristpin]

Regularly need to strip old powder coated paint from small diameter steel tube (1/2 - 1" diameter), mostly straight but some quite tight right angle bends. Usual scenario is some flaking off, some sticking like the proverbial to a blanket and the rest a mix of heavy rust with "islands" of paint.
At present scraping the loose stuff and blow lamping/wire brushing the rest.
Tried rotary wire brushes and flap wheels on hand-held drill and also with the drill clamped to the bench but sure that there must be a better answer!
Have a vision of a wide rotary brush with a groove down the middle so that it cleans half the diameter of the tube at one go.
Suggestions please!

 

[bigegg]

I'd go chemical - how big are the items you're stripping?

200l (55gal) steel barrel of caustic soda over a fire?

 

[wristpin]

Ok, so they are lawnmower handle bars! Often a U shape measuring say 2'6"long x 18" across the U.
Had considered the caustic route but a bit concerned safety and disposal wise.
What sort of concentration , grams per litre of water is recommended? Know that it will work quicker when hot but will it work at all at ambient?

 

[bigegg]

Oh.
I was thinking of chandeliers or something complicated

I use a saturated solution just add the powder to the (cold!) water and stir until no more will dissolve.

No idea if it will work on powder coat at ambient.

When hot - it eats flesh to the bone!

When cold, it will ruin clothes and raise blisters.

I use a rubber apron, gloves, wellies, face mask + goggles on the very odd occasion I use it.
Good thing is, it can go straight down the drains when you're done.

Seal the lid when not in use.

Might be better to find a shallow tray big enough to fit the handles in - or make up some sort of tank with twin legs for the handles to fit vertically.

 

[wristpin]

Thanks - I'll consider it!

 

[dannyp]

if doing loads id go chemical, if they were just one at a time and every day occourance i would be more tempted to use oxy torch with a very oxodiseing flame ****s powder coat very effectivly and quickly and the work dosent get that hot ether.

 

[Pete.]

I've got a 8" wire wheel on a bench grinder and I've yet to find something it won't take down to bare metal very quickly.

Another thing I have considered making for cleaning tubes is a hand-held tool for running belt sander belts inside out, like a backwards dyna-file.

 

[bigegg]

Thinking about it, a belt grinder with a sprung wheel (so the belt conforms to the shape of the tube) would make short work of it, is a worthwhile project in itself, and much safer than caustic

 

[Mr shiney]

Just burn it off. Its how I remove it and its also how the guys that do my powder coating do it. A propane torch is enough to remove it and will not damage the metal.

 

[bigegg]

I always imagined powder coating to be like that old 1930s(?) enamel coating which was pretty much invulnerable to heat (and wire brushing)

 

[langy]

You have discovered the major downside of powder coating I get it media blasted off, heat just seems to make a mess of it.

 

[Mr shiney]

I always imagined powder coating to be like that old 1930s(?) enamel coating which was pretty much invulnerable to heat (and wire brushing)

Nope, it is just plastic. A propane burner gets it hot enough to just burn away. Not enough heat and it just melts but does not burn off which does make a mess!!

I can clear a bike swing arm of powder coat in under 2minutes with no damage to the metal. A quick brush up, repair as needed and straight back for powder coat. The powder coaters dip it in some sort of cleaner and its ready to go. On a good day I can turn round the entire repair in a day.