My project bike has some SC aluminum spokes (wheels) and I cant decide if I should anodize them, or powder coat them to match the frame and swing arm. What are the advantages/disadvantages to powder coating aluminum?
I'd either paint them or anodize them.
I'm concerned about the powder coat baking fvcking the heat treatment on the rims.
Quote from: Speeddog on February 23, 2009, 12:30:46 PM
I'd either paint them or anodize them.
I'm concerned about the powder coat baking fvcking the heat treatment on the rims.
My concern also. I'm assuming I can get them anodized close to the same color (Titanium gray) as the frame and swingarm correct?
Also how expensive is anodizing?
Quote from: Speeddog on February 23, 2009, 12:30:46 PM
I'd either paint them or anodize them.
I'm concerned about the powder coat baking fvcking the heat treatment on the rims.
and possibly warping them to a shape not desirable for holding tires.
If you go with a hard black anodize, it's kind of a charcoal gray/black.
A clear hard anodize is a lighter gray.
Regular color anodize you can get almost any color you want.
Problem is, they fade with sunlight exposure.
Black will go funky purple, red goes pink, gold fades a bit but it's not too bad.
The 'color-fastness' depends on how good the anodizing shop is.
I've had black go purple within a couple weeks of very limited sunlight.
Talk to a local shop near you, they should have samples of what the various types of anodizing look like.
Typical lot charge will be about $100 or so for anodize.
Smooth, shiny aluminum will anodize different from a relatively rough casting, so keep that in mind too.
Different aluminum alloys 'take' the color differently too.
Clear hard anodize actually ends up a grey/brown color (kinda cool). I used it on the outer fork tubes of the M1000SS.
With an aluminum hoop, I wouldn't p'coat it because of the heat issues indicated above. If they were steel hoops, I'd p'coat them without hesitation.
so most likely paint then. [laugh]
Nate would the hoops and hubs be small enough to airbrush?
there are different grades of anodization. The hardest anodization is actually only available in a sort of charcoal finish. You'll find it on better built AR style rifles. It's not likely to change much during the service life of the rim. If anyone can chime in with the three grades of anodization, that'd be great. If not, I'll look it up! someday....
Quote from: TiAvenger on February 23, 2009, 01:12:06 PM
so most likely paint then. [laugh]
Nate would the hoops and hubs be small enough to airbrush?
I don't think so.
You'd do better with a detail gun.
Quote from: ducpainter on February 23, 2009, 05:32:00 PM
I don't think so.
You'd do better with a detail gun.
I knew that would be your answer. Im looking into em (and a compressor)
any way I can really make the beast with two backsem up? I assume I can strip them down and paint them several times without damaging the rim.
Quote from: TiAvenger on February 23, 2009, 05:34:05 PM
I knew that would be your answer. Im looking into em (and a compressor)
any way I can really make the beast with two backsem up? I assume I can strip them down and paint them several times without damaging the rim.
Not really.
Once I got them prepped it would have to be a serious make the beast with two backsup before I'd strip them. There's a zillion ways to deal with 'challenges'.
If you strip aluminum you'd need to re-etch it.
Quote from: ducpainter on February 23, 2009, 05:40:59 PM
Not really.
Once I got them prepped it would have to be a serious make the beast with two backsup before I'd strip them. There's a zillion ways to deal with 'challenges'.
If you strip aluminum you'd need to re-etch it.
Should I re-etch if I took the paint off with a grinder?
Quote from: Speeddog on February 23, 2009, 12:30:46 PM
I'd either paint them or anodize them.
I'm concerned about the powder coat baking fvcking the heat treatment on the rims.
Not enough heat to cause damage.
QuoteShould I re-etch if I took the paint off with a grinder?
Yer joking, aren't you? Sometimes hard to tell without a smileyface. :)
In case you're serious, no you can't take the paint off rims with a grinder and ever hope to get them looking good again. Plus, little sharp edged scrapes and scratches in aluminum in the wrong places might start a fatigue crack later on.
Sorry if I didn't catch your humor - sometimes I'm taking things too seriously and can't tell.
Quote from: Langanobob on March 18, 2009, 11:00:36 AM
Yer joking, aren't you? Sometimes hard to tell without a smileyface. :)
In case you're serious, no you can't take the paint off rims with a grinder and ever hope to get them looking good again. Plus, little sharp edged scrapes and scratches in aluminum in the wrong places might start a fatigue crack later on.
Sorry if I didn't catch your humor - sometimes I'm taking things too seriously and can't tell.
I was serious, :) but I should specify that I was thinking about a wire wheel on the grinder. ;) Probably a lot of hand sanding and a dremel as well. But for the sake of search. I'll re-ask my question. Does aluminum in general need to be re-etched if sanding the paint off rather than using a chemical stripper?
I'll leave it to dp to answer the etching question, rather than venture an uneducated guess (a first!). I have another related question for dp. Assuming the rims have a good quality paint job on them from the factory and they're going to be re-painted rather than powdercoated or anodized: Couldn't you wet sand the original paint, fixing any chips and then seal and/or primer them and put on a color coat without removing the original paint?
I'm just asking this because I know how much work is involved in stripping things, regardless of whether it's done chemically or mechanically.
Does this "etching" differ significantly from the result he'd get from sand blasting?
Quote from: Smokescreen on March 18, 2009, 08:45:07 PM
Does this "etching" differ significantly from the result he'd get from sand blasting?
Dunno what happened to dp, this is really a question for him to answer. I think that aluminum forms an oxide surface that isn't good for paint to bond to, thus the need for chemical etching as a paint prep to remove the oxide layer. I also think that sandblasting is OK as long as you clean and paint right away. If you leave it sit for awhile the oxide surface will reform. But a roughened sandblasted surface seems like it would bond pretty good, even if it did have an oxide coating. But this is really a question for dp and if I got it wrong I hope he comes back and straightens it out.