Rustproofing bare steel

Northwind · 14 Nov 2008 at 19:16

OK, this might be a big ask, but I'm helping one of my neighbours out with a bike project, and he's wanting to leave the steel frame as bare metal- scuff it up with scotchbrites then leave it. It looks brilliant, so I kind of agree. But he also wants to ride it, not just keep it in a vacuum pack, so it needs some sort of rust protection. He could wax it, or I've suggested ACF50, but they both leave a noticable coating, plus they're temporary- even ACF50 washes off.

Really something permanent would be the ideal, a clearcoat without paint essentially. Any suggestions? Obviously I could just use a regular clearcoat but I'm worried about adhesion to metal...

Cheers

Andrew

BigglesPiP · 14 Nov 2008 at 19:23

Make it again from aluminium.

Northwind · 14 Nov 2008 at 19:39

Good idea. But then he'd probably want to polish it and it'd still corrode

BigglesPiP · 14 Nov 2008 at 19:40

He's going to have to settle for the rat look I think.

PhillyDee · 14 Nov 2008 at 19:44

A clear coat of varnish/laquer or whatever. Or get it plated. But even then, it wont look as bare steel. Aluminium corrodes too . . . . Just takes longer and looks like white powder.

Northwind · 14 Nov 2008 at 19:56

Yeah, a simple clearcoat of some sort is going to be the plan, just trying to figure out what's going to work, if anything.

slowrunner · 14 Nov 2008 at 20:27

Good old celly should do the trick!

philjohn · 14 Nov 2008 at 21:12

If I wanted to ensure that it wouldn't rust, I'd get it galvanized - it won't look the same, but it will still have that "bare metal" look.

Vasquez · 14 Nov 2008 at 21:20

Couldn't you attach it to the battery to stop it corroding?

Northwind · 14 Nov 2008 at 21:28

Ooh,there's an idea, galvanising wouldn't look quite the same but it might at least look interesting. I'll look into that.

ShakenNstirred · 14 Nov 2008 at 21:54

Vasquez said:
Couldn't you attach it to the battery to stop it corroding?

no
as the electric are earthed to the frame

Dogbreath · 14 Nov 2008 at 22:15

Northwind said:
Ooh,there's an idea, galvanising wouldn't look quite the same but it might at least look interesting. I'll look into that.

You have to be very careful hot dip galvanising metal frames, it can cause serious distortion as internal stresses in the frame are released.

EvilDreams · 14 Nov 2008 at 22:29

So make it again from titanium.

BigglesPiP · 14 Nov 2008 at 22:38

electro-plating then more scouring might work, stop at the nickel layer, no point paying for chrome, careful not to rub through to the copper.

mrthingyx · 15 Nov 2008 at 11:18

EvilDreams said:
So make it again from titanium.

Let me know how you get one with that.

Lacquer is probably the only way to get it working properly, but that will go the way of the dodo as soon as you nip a bolt on it.

Some pretty cool stuff can be achieved with aluminium (transparent anodising is one, but pretty tough unless you really know what you're doing), and the amount you'd pay to make the frame out of it + time makes it impractical.

If using dirty carbon steel of some description, you could try 'sacrificial protection' by bolting small zinc plates to the frame at certain points: those would corrode in place of the steel, but would need maintaining...

BigglesPiP · 15 Nov 2008 at 13:55

I don't think a sacrificial anode will keep the rust spots at bay, it'll go like a brake disk does.

Northwind · 15 Nov 2008 at 13:56

OK, thanks guys... We're just going to try a regular 2K clearcoat for now, with ACF50 around the inevitable damage points where things bolt in. o idea how well it'll work but he can always clean it off again

Glaucus · 15 Nov 2008 at 14:00

How about some sort of matt finished clear coat.