Framebuilders - Clearcoat on bare steel?

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View Full Version : Clearcoat on bare steel?


stevefaletto
08-12-08, 02:47 PM
I've ordered a new steel frame and I was thinking about if it would be possible to pay someone to powdercoat just clearcoat onto it, or if another method would work better. I'd like to keep the look of the bare metal, but protect and gloss it. Thoughts?

this is a photo of the frame material

http://alienbikes.com/products/lug_small.jpg


unterhausen
08-12-08, 10:45 PM
I don't really know much about powder clear coat, but I wouldn't do it. I worked with someone that made an absolutely beautiful frame and polished it. Then he got it clear-coated. It developed a spider web of rust underneath. Actually looked really cool, but I imagine he had it painted later.

lightningcow
08-12-08, 10:50 PM
I actually prep and paint cars. It would take quite a bit of prep to keep it rust-free for a while. You could try some Ospho, a rust inhibitor, and then sand and clearcoat. I still think it may end up rusting though.


stevefaletto
08-13-08, 07:50 AM
hmm. would a rattlecan clear be any better? This may not be such a good idea in the end.

lightningcow
08-13-08, 08:15 AM
Rattle can would be the worst. It's just not thick or strong enough. Automotive clear or powder coat would be the best, but If any moisture is caught underneath it will eventually rust. Like I said though, Ospho may help with that.

sstorkel
08-13-08, 09:54 AM
Aren't you guys being a bit paranoid? Is the frame really going to start rusting during the 5-minute walk from the bead blasting booth to the powder coat room? Steel frames are powder coated all the time! It doesn't seem to be that the color of the powder coat (clear vs. opaque) should have a big impact on whether the frame will rust or not...

To the OP: I think you'll be fine with powder coat. If you're worried about rust, and honestly I would not be, ask your powder coat shop about it. I'd also ask to see a sample of clear powder coat over bare metal so you know what your frame will look like. Best if you can get your builder to send you some off cuts and convince your powder coat shop to run one as a test.

unterhausen
08-13-08, 11:13 AM
the frame I saw this happen to was not powdercoated. Given that, there are chemical reactions that go on underneath your paint job, and it doesn't matter to you because it's hidden by the paint. I think the OP should realize that he's probably one of a very select group of people that would find this attractive, and the rest of that group of people take a different frame size. So he could never sell it.

And rattlecan clear is not as good as the finish I saw. I guarantee there will be rust under rattlecan clear. Polished steel is significantly more rust resistant than sandblasted steel. The frame in the picture has been sandblasted/media blasted. I suspect that sandblasted steel may promote rust faster than almost any other finish.

wlhutch
08-13-08, 07:27 PM
Check out Rivendell's BOMBADIL (clear-coated version over bare steel) http://www.rivbike.com/products/list/bicycle_models#product=none
http://i3.photobucket.com/albums/y66/wlhutch/bombadoubst1.jpghttp://i3.photobucket.com/albums/y66/wlhutch/BOMBADOUBHT2.jpg

stevefaletto
08-13-08, 08:28 PM
yeah that's what i had in mind. thats such a ridiculous bike, but awesome. I'd like to know what processes they use to do that

unterhausen
08-13-08, 10:29 PM
they just clearcoated over a bare frame that really hasn't been processed in any way. thinking it must have been powdercoated

stevefaletto
08-16-08, 05:22 PM
the frame says "phosphated" on the box. dont know if that has anything to do with powdercoating, but i'm still thinking about going the clearcoat direction.

duane041
08-16-08, 10:53 PM
the frame says "phosphated" on the box. dont know if that has anything to do with powdercoating, but i'm still thinking about going the clearcoat direction.
By putting on a phosphate coating, you inhibit further corrosion, and also give the surface of the steel some profile, or 'tooth', which helps your primer to adhere better. It also prevents the frame from flash rusting before it gets painted or powdercoated.

NoReg
08-16-08, 11:12 PM
I have a friend who just bought a clear coated Brompton. Looks great in the pictures he sent me at the time. I think everyone is right. Bad things may happen. Looks cool and may be fine if you live in Death Valley. I probably wouldn't do it if I comuted every day in Seattle.

Overall I think frames done this way can look awesome. I am not as convinced that the bikes look good. The overall bike effect can be a little blah. Looks awesome at 3 feet, looks crap at ten and beyond.

Torchy McFlux
09-05-08, 05:00 AM
Thin little veins of rust show up sooner or later. I've seen it first-hand.

That Bombadil is a prototype, I believe. Neat way to check the quality of brazing. No Bondo touch-ups allowed.

LittlePixel
09-05-08, 08:00 AM
Brompton folding bikes do a powdercoated clear steel frame. Haven't read any reports of rusting. I don't really see how rust could form with no exposure to oxygen.

poopisnotfood
09-05-08, 08:35 AM
That is an impressive frame. I like the look personally.

zzzwillzzz
09-06-08, 12:11 AM
oh that's hideous, it looks like it steam powered or something. and if you're going to go through the trouble of building that monstrosity then that extra top tube should have lugs as well. you shouldn't half-@$$ something like that