Getting rid of rust.....for good.

[theonetruegreg]

Did a search and only found one short comment about it. So figured I'd put it back out there.

Having been a restorer of vintage (1930-1960's) motorcycles for an awful lot of years now, I have to deal with serious rust on parts that had insanely low (500 or less sometimes) runs of production. Have to save them, as replacement is impossible, and machining a new part just wouldn't fit the end goal on external parts.
I have always, and always will continue to use, 85% phosphoric acid (15% glycerin as a thinner/carrier).
Soaking for small parts that I can, and brushing on for larger bits (frames and combustion chambers in my use). Generally let sit for about a day (with the exception of valves, which will have the coating eaten away, I only leave for a couple of hours).

After you've wire brushed as best you can, set em to work. Serious corroded bits take a few days of work, but the results are always great.

Rust inhibitor products have too much extra crap in them to be terribly effective for seriously messed up parts.

Working through my own rig, bolt-by-bolt, cleaning and painting/sealing every single part. Works like a charm.


(added bonus: if not powder-coating, Appliance Epoxy is a pretty serious finish for clean metal parts, which I use quite a bit)

[rocklaurence]

Where do you get glycerin?

[theonetruegreg]

Where do you get glycerin?

Just about any grocery store will have it in first aid supplies. I buy it from my local walgreens

[REDONE]

Less patience! More powertool!

[rlars7]

Did a search and only found one short comment about it. So figured I'd put it back out there.

Having been a restorer of vintage (1930-1960's) motorcycles for an awful lot of years now, I have to deal with serious rust on parts that had insanely low (500 or less sometimes) runs of production. Have to save them, as replacement is impossible, and machining a new part just wouldn't fit the end goal on external parts.
I have always, and always will continue to use, 85% phosphoric acid (15% glycerin as a thinner/carrier).
Soaking for small parts that I can, and brushing on for larger bits (frames and combustion chambers in my use). Generally let sit for about a day (with the exception of valves, which will have the coating eaten away, I only leave for a couple of hours).

After you've wire brushed as best you can, set em to work. Serious corroded bits take a few days of work, but the results are always great.

Rust inhibitor products have too much extra crap in them to be terribly effective for seriously messed up parts.

Working through my own rig, bolt-by-bolt, cleaning and painting/sealing every single part. Works like a charm.


(added bonus: if not powder-coating, Appliance Epoxy is a pretty serious finish for clean metal parts, which I use quite a bit)

Interesting. I have been using rust-mort as a stop gap until I can weld in new metal. After it rained, my spots turned white where I had treated the rust.

Would like to hear more about your system. How much rust do you remove prior to brushing on your mix? How many coats of mix? When you say glycerin, what kind do you use (vegetable, etc.)? Prime and paint immediately afterwards?

How does it hold up long term? Thanks for the advice!

-Rob

[theonetruegreg]

Interesting. I have been using rust-mort as a stop gap until I can weld in new metal. After it rained, my spots turned white where I had treated the rust.

Would like to hear more about your system. How much rust do you remove prior to brushing on your mix? How many coats of mix? When you say glycerin, what kind do you use (vegetable, etc.)? Prime and paint immediately afterwards?

How does it hold up long term? Thanks for the advice!

-Rob

The one I use is veg-based, but not sure if it matters.

Not a system I developed, old-timer stuff that I learned from a Vincent restorer long way back.

I brush off as much loose stuff as I can with a simple wire brush (I use steel brush on heavy parts with a lot of material like frames and a brass brush where I dont want to get into it too much like sheet metal or combustion chambers and pulling heavy carbon off of aluminum pistons). Once quick pass with the acid on a brush (or toss bolts and small parts in a bowl filled halfway, it foams up a lot, so don't fill the bowl) and let it sit for a day, then a quick-over with a brass brush, til is back to shiny clean steel. (one shot'll do for surface rust, for deeper, more corroded bits, will take a few goes.) If it's gonna be a while before I can paint or finish, I'll just coat the part with oil to keep the air off.
Long term, it holds up fine, you're back to clean metal. Prep and paint it right, and it'll last same as any new part.

Not a magic cureall, still takes work, but works a lot better than the rust removal/inhibitor products I see people using.



(also, wash it off your skin right soon if you get it on you, it'll itch for days if you don't)

[jaber]

Thanks for sharin guys, Great tip...