Painting tank

[Laptop_geek]

Hi Doug,
2-part paint is the elephant in the room.
You buy the stuff from automobile paint supplies stores that you find in the yellow pages.
The smallest (1 pint) can of pigment costs ~$60. Cost can go to 5 times that for fancy metalflake paint.
Then there's the catalyst that makes it harden and the extender that thins it to spray nice.
The last two are not colour-specific so you can buy bigger cans at least.
Your least material cost to paint a gas tank will be ~$100.
You will be left with ~1/2 of the pigment plus most of the catalyst and extender for use on other projects.
And yeah, a quart can of acetone to clean out the Preval.

I just some 2k urethane paint by Nason, my costs are below (US $)

1 quart of color (specially mixed - BMW color TiAg, metallic flake added) - $40.01
1 each of reducer (looks to be a 1-2 quart can) - $11.55
1 each of activator (enough for the color and clear) - $13.60
I already had leftovers from a separate project for the clear so I didn't have to buy any, but the activator works with it.

Total (after tax) - $71.19

I should have enough to paint my bike, and the trim on my BMW. I can scan the invoice if you'd like. I buy everything from a local paint supply store called ColorMatch.

I had all of the other stuff already for the prep, so that didn't cost me anything.

Here is what we painted. We only painted the plastic trim that goes around the doors/bumpers.

[zookey]

Our autoparts store can load spray cans with auto paint. It is an alternative to having to buy a compressor and paint supplies. A 16 oz spray can is enough paint to cover your tank and side covers with at least 3 - 4 good coats of paint.

The only draw back to the cans is that once it is mixed you need to spray it within about a week. I have found the sooner you use it after they mix it and load the can, the better it sprays and lays on. The older the can gets the "thicker" the paint seems to come out of the can.

Cost of one can is about $25.

[jjz28]

I was thinking of just getting a good high temp paint and then spraying that spraymax clear over it to protect it from the gas. I live in WV and i am sure we cant get auto paint put in an aerosol can, we cant even get ngkbp6es, we are so backwoods, behind the times.

[Lbrown311]

I am doing the exact same thing with my painting. Using a high temp decent spray can paint and will then use the spraymax clear. I am also giving each paint the proper amount of time to cure in room temp which is one week or 7 days for the spray color. Before clear coat I will sand with 1500 and 2000. I used 4 coats of the color to leave myself room to sand. I think that is the most price effective way to go if you can't afford someone to do it for you. But that is only one mans opinion

[crazy steve]

...Before clear coat I will sand with 1500 and 2000...

DON'T sand the color coat unless you need to remove flaws. If you do sand it, sand lightly with 220 or 320 paper. Going finer will make the paint too smooth, and the clear coat won't stick well...

[jjz28]

Let us know how it turns out lbrown and I will know whats up. I am glad you let us know that steve.

[bikerphil]

DON'T sand the color coat unless you need to remove flaws. If you do sand it, sand lightly with 220 or 320 paper. Going finer will make the paint too smooth, and the clear coat won't stick well...

I tend to disagree with the not wet sanding the color coat, you won't get a nice mirror finish without sanding it with at least 1500. JMHO.

[Lbrown311]

Well which is it gentleman. I am gonna have to put you two in time out together so you can settle your differences. I agree with both thoughts. If you sand with 220, can you polish the clear to get your mirror shine and if you wet sand with 1500/2000 will the clear actually still stick well enough to NOT chip? I feel like I am in the rack right now. I will just stick to the handle bar controls till you two get your Sh*t together

[bikerphil]

If the surface below the clear coat is not smooth, you can polish your clear coat all day long and it still won't shine. That is where the mirror finish comes from is the silk smooth color coat. Maybe 220 is smooth enough, I don't know for sure. A way to simulate what your color coat will look like after the clear is applied is pour some water on it, after the paint is dry of course.

[Lbrown311]

Well if water simulates the clear coat then it wont really look that bad even with 180 dry sanding. I wet sanded with 600 after I used 180 on my side covers and when it was wet it looked pretty decent. If you are talking the difference between 2000 and 220/180/320 then I don't know the answer to that, but even 180 looks ok when wet. Maybe a good compromise would be to use 320 or a step up and go with that since you will get good adhesion and a pretty nice finish. The clear when polished WILL give it a beautiful shine regardless if it is a mirror finish or not. After one coat of the base coat I could see myself in the paint while taking pictures. I would feel safer with better adhesiveness than with a little more mirror or gloss type finish. It will look better than 40 year old paint either way Thats just my opinion. At least I have a better idea of where to go from here now after all this discussion

Thanks for the thoughts. Glad I could take something from someone elses thread, so also a big thanks to Jeff in Tampa.

[crazy steve]

I tend to disagree with the not wet sanding the color coat, you won't get a nice mirror finish without sanding it with at least 1500. JMHO.

Phil, I used to think that too, but my paint jobs always chipped easy too.

I get a magazine called 'Auto Restorer' and they've got a pro guy by the name of Larry Lytle that does all their body/paint 'how-to' articles. He's the one that says not to use too-fine paper under the top coat. He recommends not doing any sanding of the last color coat before applying your clear in fact. But for this to work right, you need a good, smooth even finish for your clear to go over, but not too smooth (like what you'll get with 600 or finer paper) or the top coats won't have enough 'tooth' to bond to.

Once you've got your top coat on (whether it's clear or a single-stage paint), then you bring out the ultra-fine paper...

I've been following his directions, and he hasn't steered me wrong yet.

[bikerphil]

Yep, that all makes sense Steve.

[clcorbin]

The only reason to sand the color coat is if you have trash in it from shooting in a dirty environment. The clear coat is a relatively thick coat. It will cover the sanding scratches from even fairly coarse paper. If you want a truly mirror polish, you have no choice but to sand the final clear coat to level everything out (orange peal which is almost IMPOSSIBLE to completely avoid with today's low/zero VOC paints and HVLP low VOC guns for example) and then polish back up to a near perfect shine. And, if you are going for that fantastic shine, then you need to put a couple of extra clear coats on anyway so you know you have plenty of thickness to sand down...

And also remember: the paint has a recoat window for a reason (assuming curing paints, not evaporative drying paints). The chemical structure of the paint is still soft enough during the recoat window so that the next coat will actually soften and chemically bond with the previous coat. Once the paint is out of the recoat window, that can no longer happen, so you are left with a physical bond instead of a chemical bond, which means you have to sand it to provide the mechanical "bite" for the next layer. The short summary: Building the layers during the recoat window will ALWAYS lead to paint that has much better mechanical bonding than sanding it afterwards and painting.

The older solvent based lacquers are a different story. They do not have a recoat window because they do not cure. There is no cross-linking between polymers, so you can always soften them with the next coat, no matter how much time has passed. This is also why you can wash the stuff off with gasoline as well.

[Lbrown311]

Now we're really getting in depth. Great info for anyone who is wanting to paint anything. So, should the clear be applied during the base coat window to create a chemical bond with the clear and the base coat? I would assume they would have to be of the same chemical compounds regardless of manufacturer to make that bond happen. Or do you let the base coat cure for its alotted time and then clear it? I would think as long as you let the very last coat, whether clear or color(if you're not clear coating) cure, then you will have a tough paint job....obviously the overall quality of the paint job depends upon the quality of the product you use. So really my only question is when is it best to apply the clear coat....before your window is up or after you color has cured fully.

I figure if I am going to paint...especially with inferior/affordable paints...then I want to make sure I can do at least a half ass decent job.

[daveyg]

On my last rat bike I used dupli-color truck/van/suv rattle can paint over rust-oleum primer, I had about 10 coats of color when it was all said n done, was kinda a satin silver. I never poured gas on it, but every fillup would get a drop or 2 on it, and I wouldn't touch it, just let it evaporate, and I never once had it bubble up or wash out... maybe I'm just lucky.