Bead Blast Rust or Use Rust Converter?

[Susan_in_SF]

Hi Guys,

As many of you know, I am a poor newbie who is onto vintage machinery and tools. Hence, most of the stuff I can afford is rusty, to one degree or another.
I found this study that tested and compared various rust converters:

https://www.ncptt.nps.gov/blog/comparative-study-of-commercially-available-rust-converters/

Rust-oleum Rust Reformer came out the winner.

Since Rust-oleum Rust Reformer supposedly protects the metal from further rusting, I wondered when would bead blasting a rusty item still be preferred over converting the rust into a protective coating.

Also, for the times where bead blasting is a better option, is there anything better for rust prevention than to immediately paint with primer?

I am just a helpless woman looking for assistance.....lol ;-)

Thanks,
Susan

 

[Al 1]

I have used what ever I have. As long as the metal is cleaned off before painting: oils etc. Washed off with liquor thinner , simple green etc.
I have never got rust coming through from metal machinery. Warm metal seams to take paint better. I have warmed up metal and sprayed painted in freezing weather and it has held well. Al.

 

[GL]

When I can, I blast. But, for moving parts the grit can get in between things if you can't get it apart to clean up after. Blasting gets into the nooks better than a wire wheel sometimes and better for small parts in a cabinet. Metal will flash rust after blasting, so primer is your friend - you probably didn't get it all so I use the rust converter primer there too. I haven't used soda for media yet, but 80 grit beads will take out detail, smooth machined surfaces, and edges if that's important. I'm far from an authority on paint, but I do know rust prevention is more about prep than what's in the can if you use decent materials.

 

[mikey]

I think Evaporust is really useful for small items with surface rust. Works good, works fast and doesn't eat up the parent metal.

On larger parts, I use the electrolytic process. I've done parts from screws to entire lawn mower chassis with this process. It removes all rust and paint, thereby saving a ton of work. It is pretty safe and mostly non-toxic. If I could only do one thing to remove rust, this would be it.

I use "The Must For Rust" on and off. This is a Phosphoric Acid solution that works pretty okay for surface stuff. I dilute it and spray it on parts that come out of the electrolytic bath. This prevents flash rust and can be primed and painted right over it.

Most of the time, I am trying to restore a rusty thing. Haven't had to resort to blasting anything yet.

 

[hman]

Washed off with liquor thinner ...,

Plain water or club soda?

 

[NortonDommi]

I am just a helpless woman looking for assistance.

We all sincerely doubt that Susan and woe to you if a 3rd-wave feminist finds out you said that .

My preference is for a Tannic Acid based product called Emer Tan made by Henkel Industries. When they acquired the rights to make this the took it off the market so as to sell another of their products that has an Acrylic sealer built in. I just managed to obtain some,(at nearly 4 times the price it used to be),as apparently the produce small batches every now and then for some major customers. I like it because of its capillary action which lets it creep a long way and used before stripping old machinery also aid in the action of penetrating fluid after conversion. If making something similar Tannin from your local home brew shop is superior to super strong Tea and very cheap, Phosphoric Acid however is a bit pricey.

As to blasting, unless you are prepared to do a total strip down and have old taps in all required sizes to properly clean out tapped holes forget Glass beading. Also don't Glass bead any Aluminium to be polished as it makes it about 10 x harder to get a decent finish due to surface compaction and microscopic traces embedded in the surface,(ask me how I found this out).
Wet Soda blasting is really safe and an anti-corrosive is usually added to the liquid carrier so all that is required before paint or any other surface treatment is a rinse.

 

[Susan_in_SF]

We all sincerely doubt that Susan and woe to you if a 3rd-wave feminist finds out you said that .

My preference is for a Tannic Acid based product called Emer Tan made by Henkel Industries. When they acquired the rights to make this the took it off the market so as to sell another of their products that has an Acrylic sealer built in. I just managed to obtain some,(at nearly 4 times the price it used to be),as apparently the produce small batches every now and then for some major customers. I like it because of its capillary action which lets it creep a long way and used before stripping old machinery also aid in the action of penetrating fluid after conversion. If making something similar Tannin from your local home brew shop is superior to super strong Tea and very cheap, Phosphoric Acid however is a bit pricey.

As to blasting, unless you are prepared to do a total strip down and have old taps in all required sizes to properly clean out tapped holes forget Glass beading. Also don't Glass bead any Aluminium to be polished as it makes it about 10 x harder to get a decent finish due to surface compaction and microscopic traces embedded in the surface,(ask me how I found this out).
Wet Soda blasting is really safe and an anti-corrosive is usually added to the liquid carrier so all that is required before paint or any other surface treatment is a rinse.

Thank you NortonDommi. If any feminists get on my case for saying that, I bet they don't own a South Bend ;-) I can say stuff like that since I know I am capable, lol.

 

[psgflier]

One of the things you have to watch out for with mechanical rust removal ( blasting, wire brush, etc.) is that metal can get peened over pockets of rust and the rust will explode out at a later time, rust never sleeps.
Most of the rust converters I've used work best on a light coat of rust, but the loose rust and scale needs to be removed. I've had good luck with a product called Corroseal (sp).
If you get cleaned up to bright metal a rust converter is not necessary and a good primer and paint , preferably self-etching, works fine.
If it's a bare surface you just have to scrub it down and keep it oiled or waxed.
Almost all of the rust removal methods, mechanical or chemical erode metal. Electrolysis doesn't and I prefer it, especially on thin sheet metal.

 

[MrWhoopee]

I was quite surprised at how well white vinegar did the job.

 

[NortonDommi]

MrWhoopee Any Acid will work to remove rust, Vinegar, Oxalic, Acetic, all are common ones around the house. Tannic Acid from strong Black Tea is another. These are all mild Acids so fairly safe for Humans as well as the metal but they all remove metal as well as rust.
Converters are different in that the actually convert the rust on the surface to an adherent inert layer that resists further corrosion and provides a porous substrate for further treatment such as an oil, wax or paint. A converter treated with a drying oil can leave a tough attractive finish that will last indefinitely inside.