after removing rust down to the bare metal, what's the best way to protect bare metal parts from rusting again, keeping a natural finish?

[ezeeetm]

Hey! Post subject pretty much says it all. For some old bike parts (like chainrings, crank arms, and small bits of steel hardware (screws/nuts/bolts, seatpost clamps, etc), I plan to strip them down to bare metal with wire brush, sandblast, and/or sandpaper depending on the part, size and amount of rust. Then, give them a good surface cleaning with acetone or rubbing alcohol.

Now I have a nice, clean, rust free metal surface. For a painted part, now is when I would prime and paint.

However, the many parts like the ones I mentioned above and others, I want to just keep natural metal look, but don't want them to rust (easily) again. Are there some commonly accepted methods/techniques/processes in the bike restoration community for treating and/or coating bare metal to keep a clean bare metal finish from rusting?

Thank you! This forum is amazing!!

 

[Rivnut]

It's a pretty simple DIY process to zinc coat things. Takes a sacrificial zinc anode (anything zinc) some grocery store items, and a a battery and some wire. Eastwood Company makes a Diamond clear for bare metal.

 

[bloo]

You can clearcoat, or put on linseed oil. IMHO neither works that well but is better than nothing.

I keep a zinc plating bucket around like Rivnut mentioned. On automotive stuff I use it all the time. When a part has been rusty, the surface area is huge due to the pitting, and will rust much faster than a new bare part would. A little zinc can be a miracle to preserve parts like this.

On bicycle stuff, you might think twice about completely stripping parts. That just isn't what people are doing in 2020, and it would probably reduce the value of valuable parts FYI.

I used one of the following recipes for the zinc. It is not show quality, but great to hold back the rust. You can probably get show quality zinc on small pieces if you are wiling to spend a lot of time babysitting it. Read the whole thread because one of the earlier postings had the polarity backwards (a big oops).

DIY Zinc Plating for Donor Nuts and Bolts

If you have rusty donor parts and have not read the thread on old school electrolytic de-rusting, then do yourself a favor and take a quick look... several forum members have posted pictures that are almost too good to believe... but the process works as advertised. One problem with...

thefactoryfiveforum.com

 

[abe lugo]

Some of the hotrodders use Gibbs metal prep.

 

[Ernbar]

I wiped boiled linseed oil on chrome parts over a year ago and I haven’t seen rust come back so it’s worked for me so far.

 

[Steve Baltera]

I have a bare metal project with GIBBS OIL on it for about 6 years. NO rust. You can find it on amazon...

 

[Boris]

Some of the hotrodders use Gibbs metal prep.

I've got a bottle of blue Metal Ready that I've never used. Is that basically the same as Gibbs for staving off rust for any great length of time? I have just been using BLO or paste wax.

 

[vincev]

Ace has clear enamel spray can.Either gloss or matte finish

 

[atilly]

Krylon K05562007 Crystal Clear is my goto right now.

Does anyone have experience with Flood Floetrol?

I am intrigued with trying the stuff, apparently it can be applied with a brush which intrigues me. I don't have good control with a shaker-can and perhaps a brush would help with that.

 

[SirMike1983]

I've used clear enamel, clear poly, clear coats of various types on bare metal. Sometimes it works, sometimes it does not. The metal has to be very clean and carefully prepped. Contamination, rust that is not addressed, etc. can cause the rust to continue underneath the clear coat. If you want to clear over bare metal, make sure your prep is carefully done.