Fuel resistant paint

[quandryron]

I painted my bike last year with the cheap stuff at walmart. It's holding up well. Seems reasonably fuel resistant. I can't say for sure as I wipe up any spills asap when they happen. Plus, the finish really impressed people for the ten dollars I spent in paint and clear. The secrets in the prep work. The defects really pop out when it's dry.

[mf70]

I don't care how much the can says "fuel resistant," pre-mixed spray paint isn't made to harden. The way it dries is by the moisture evaporating from the paint, leaving color behind. That's how it says liquid in the can for years.

I'm no paint expert, but I have some knowledge of resins. Conventional hydrocarbon solvent paints dry in two stages. 1) As you said, the solvent (generally not moisture except in latex paints!) evaporates. 2) Critically, the binder in the paint then reacts with oxygen in the air and cross bonds, creating a chemically stable polymer.

At a microscopic level, solvent-based coatings leave pores that can let solvents (such as fuel) re-penetrate the coating. Catalyzed coatings don't need to depend on evaporation, and have a less porous structure.

MarkF

[skreemer]

here's some stuff that the guys on the SOHC Honda site use to paint thier tanks... Two part catalyst clear coat that's chem/fuel resistant... called spray max

http://www.toolweb.com/itemDetail.cfm?partno=KWA3680061

[spyug]

Spray bomb finishes are generally not impervious to gas and as already stated you need a catalized system as used in auto body paint facilities.

While 2 part systems are more expensive than spray cans, the finish is going to be superior and stand up better to gas spills and stone chips.

You can lessen the cost quite a bit by using spray bombs for your colour coat and topping off with a two part clear coat. As mentioned previously, you need to ensure that the two paints are compatible. Oddly enough, I have found the cheaper brands of rattle can enamels to work well with the PPG Urethane clearcoat I have started to use. You should experiment a bit. Find the paint you like...shoot onto some tin.....clearcoat and see what happens afte an hour or so.

Using the 2 part urethanes , you will need to use a compressor and paint gun but even the $50 electric 1/4 horse compressors will work. For best results, I would invest in an HVLP gun ( high volume low pressure). All you need is a touch up gun ( 4 to 6 ounce capacity). they run a bit more than standard guns but places like Harbour Freight or Princess Auto here in Canada often have them on for $20 or so.

Painting starts with the best finish on the piece being painted and all blemishes will show through. Take the time to make the piece smooth. Use a good quality undercoat/primer/surfacers. Sand with 600 wet/dry. apply colour coat (s) sanding between each coat. Sand again before applying clear coats and finish off as suggested with 1500 to 2000 wet dry. Buff out with polishing compund for the amazing shine.

With spray equipment there is a bit more fiddling ( i.e. setup of paint area, cleaning of equipment) but it is well worth it for the superior finish you will gain. Two points on safety.....always use a good quality spray mask rated for paint as these 2 part paints can make you really sick if inhaled....(they will clog up your lungs) and set up your paint area in a well ventilated area.

the first time you paint with these products it will seem like a lot of effort but the more you do it the easier and faster it gets. You never know, you might be good at it and start a second career or part time job at least.

Cheers and good luck,
Spyug.

[Bopi]

Ill repost this if you like:

You can use automotive paint with hardener and apply it with this. It works great.
Retails for $10 bucks.

http://www.prevalspraygun.com/howto.htm

[gsgeezer]

I would clear coat it, or use flat black, as suggested!

Be sure to tape evenly around the lip of your tank fuel bung, or filler neck and cover the hole and about an eight of an inch down the filler neck. Remove the tape after the first day, but if you don't let the rattle can clear sit about a month, as already mentioned, be prepared for gas to eat through, or bleed under the paint around the filler neck. Good luck!

[robertbarr]

If you were wondering how there can be a 2-component aerosol can, well, so was I. I recall the Rawlplug epoxy system which has a diaphragm separating the components. You stab a tool through the diaphragm and then stir. It's really an ingenious solution.

Anyhow, here's another site about the SprayMax. It would really help to know German, though!

http://www.kwasny.com/en/b2/p2400.html

You can see the two components kept separate in that inner cylinder, and apparently some mechanism for breaking the cylinder. If someone knows German, maybe they can translate?