Topic: should i paint my tank over existing paint, or strip to metal?

[uwjberg]

so what do you all think? the paint job on the bike is fine now - not the best job, but ok. i'm going to change color, and i want to see what will be better. keep in mind that i'll be doing a rattle can cheapo job, using the methods i've seen on here (in oterh words, it won't be a professional job).

what do you all think? sand the paint down so the new paint can adhere? or strip it all the way down to metal?

[ColinMc]

Depends on what's on there now...original paint? Rattlecan job by someone else? Laquer based? Enamel based? If you don't strip the old paint off i'd make sure to at least get a can of sealer to use first to help avoid any lifting or other odd stuff.

[wildcatmahone]

Strip away man! You dont know if the paint your gonna use will be compatible with the stuff already on there you may have adhesion issues. IMO it's best to start from scratch and use a tried and true method to get the best results possible. 

[speedy gonzalais]

rub the tank down with fine sand paper the paint will stick it would be better to use primer as well

[uwjberg]

not sure what's on there now - just know it's not original. how do i tell what kind it is?

if it's not compatible, would i have adhesion issues even sanding it down and using a sealer?

[NickC]

On my tank I had roughly 4 coats of paint on TOP of the original. Stipped it down to bare metal.....

[wildcatmahone]

Better to be safe than sorry strip the f*ck outta it...

[KingCustomCycles.com]

Aircraft paste stripper from Walmart, get the quart can, the spray is junk.  Strip all the way down to metal and give her a scrub with detergent and a scotchbrite pad, Bondo dings, spray on primer/sealer, fill nicks with spot putty, reprime, base coat color, sand with 600 lightly and clear coat.  It is fuel proof and glossier (sp?) than factory. It is THE only way to go and that is a hard learned lesson from 35 years of painting mistakes and half ass attempts. 

[Hush]

Hey cheers for that comprehensive rundown KC, I'm in the same boat having rubbed the original paint back to bare metal.
The original stripes are a pain in the ass, they stick to the sander and peel forever, if you are doing an el cheapo rattle can job I'd leave them there and use them for a pattern for your new colours.

[NickC]

angle grinder + twisted wire wheel took care of my problem extremely fast

[wildcatmahone]

Stripping or wire wheeling is the only way to go, I would NOT go anywhere near a fuel tank with an angle grinder that sheet metal is thin enough to begin with....you crash the bike and sparks and BANG!  Give it a generous wipe with acetone before spraying....Check out my rattlecan thread hope it helps ya.

http://forums.sohc4.net/index.php?topic=36659.0

[NickC]

a wire wheel really doesn't take much metal off, unless you are applying some MAJOR pressure. I was using a wire wheel on an angle grinder, to clarify

[mystic_1]

Aircraft paste stripper from Walmart,

+1

Tal-Strip brand Aircraft stripper is great stuff, should eat through most finishes in short order.  Make sure to protect you skin if you use it, it's über-corrosive.

mystic_1

[coyotecowboy]

Rattle can cheapo job?  Scotch-Brite, wipe and shoot that #$%*!!  If it lifts, you're out the cost of a can of paint. Big deal.  If you don't like it then strip it

[Old Crow]

From Honda to your shop, that tank can't have had incompatable anything on it (could it?)or it would have come off (wouldn't it?)and been re-done by someone along the way. (wouldn't they? (;-)

what possible esoteric wierd science would yer average CB owner toss in the mix?

Spray/rattle a hidden test corner on your tank and find out.

My spray booth time was short but down to steel isn't neccesary unless you want exposed metal in the finished piece. This not a pro job, right! It's rattle can. But it can look really good anyway.

Sand with 200-250 on the old finish, fill the canyons, and re-200 till sweet. Tack cloth, prime, 320 like your buffing a babies butt, miss nothing. Spray paint, 320 between as many coats as you lay on. Minimum four layers.
I put my bits in the sun to warm up. Spray with the ambient breeze. Do not try to cover in one coat. Definition: one coat is a complete, even, all over coating. So... it may take several gentle sparing "applications" waiting in between for 30-60 seconds to get some tack. Build easy to get one real coat. Resist the urge to "hit'er again" or it will run.

All the fuss reduces the orange peel, the runs, or flat spots of old finish trying reassert.
I'm from the rat bike school, but it can still be sweet.

[ColinMc]

Unless it's originally Laquer paint...which it probably is, or if someone rattle canned it with laquer, which they might have, and you try and put enamel over the top of it...or someone sprayed it with crappy enamel that never REALLY fully cures, and you try and put anything on top of that.

But either way, get a can of something, scuff that tank down, shoot it and see what happens. Worst case scenario you are back where you started from, best case scenario it comes out good enough for what you are going for and you are done. Sanding between coats with spray paint seems like kind of a waste to me. You don't even do that with automotive grade finishes. Just scuff the tank down with 220 to smooth things out, then finish sand with 600, then spray that sucker down with light coats until you are happy with the coverage.

If it was me and I was doing it as cheap as possible for the best possible result on said budget. Scuff it down with a grey scotch brite pad, tack it with a tack rag,spray can of paint, be done with it. If it lifts...then start from scratch.