What primer to use?

[slopster]

I'm getting my bike ready for painting. I'm going to get a friend whos a pannelbeater to do the top coats but I'm doing all the preperation myself. What primer should I use. It will be a combination of plastic fairings, fibreglass fairings and the steel gas tank. I'll probably just buy the primer in in spray cans but could probably get access to a paint gun if it was going to make a difference to the finnish. Needs to be one that I can sand because I'm sure to cause a few runs as I put it on.

[dhunt]

When my brother repainted his bike recently he got a 2 part primer. That you mix the two parts then spray on with a gun. That was what he was recommended and seemed to do the trick.

[imdying]

Use a gun. It won't make a big difference to the finish, because you'll be sanding it anyway, but due to the number of cans you'd need, it'll make a huge difference to the price.

Just use a urethane primer, any body shop will be able to recommend one to use. Do not use a 2 pak primer, 2 pak painting systems have things like isocyanides that you definitely do not want to fuck with.

[Motig]

OK I'm missing something here. Wouldn't the guy thats doing the top coats be able to tell you? You would have to use an undercoat thats compatible with the topcoat otherwise your wasting your time and will have to start from scratch again.

[Busy]

use the same type of primer as the paint being used or it will sink in a few months

[Steve Gauge]

use debeer primer 2 pac 2 parts , its reasonable priced , easy to sand ,definitlety dont use a spray can because it will be enamel and will react with main coat , or pay the money and get the painter to do it ,saves doing it twice

[F5 Dave]

Go into the paintshop & tell them you want to paint 2 pac & don't have a air fed mask. If they have a conscience they won't sell you any. Heck take up smoking & Drink lots of Diet coke.

[slopster]

Go into the paintshop & tell them you want to paint 2 pac & don't have a air fed mask. If they have a conscience they won't sell you any. Heck take up smoking & Drink lots of Diet coke.

I can use diving BA from work but could I just use an (army) NBC (nuclear, chemical, biological) mask with a charcoal filter?

[crazybigal]

for the plastic you should use a primer with a flex agent in it.
depends on your top coat, some react worse than others, id just sand it down and get your mate to prime it when he paints it otherwise it will end up costing more to fix it in the end. been there done that got the frickn t shirt.

[crazefox]

give me a yell i have some good primer i can sell you 1l for 70

[XP@]

I used Dulon primer and paints, mixed up by me. was quite difficult to get the hang of but early cbr600's have a lot of body work!
For the fairing I added in a rubberising solution to help the paint flex.
Dunno if it helped much...

[steveyb]

Dulon lacquer is nearly the only option for do it yourself painting, but is very very old technology. It is an emulsion-based system that relies on solvent evaporation to form the paint layer.
Newer 2K (2 pack) paints are isocyanate based paints with as it says, two chemical components (actually many chemical components, but two parts to the polymer system). Isocyanates react with the correct second component to make polyurethane polymers, which forms the paint.

These paints MUST be painted with a positive air-feed breathing system as isocyanates are highly toxic and carcinogenic. ie they will poison you.
They must also be heat treated after applying inorder for the polymerisation to occur.
They are also more flexible and resiliant than Dulon types of paint which need a plasticiser to be added for fairings otherwise the paint will crack very easily.

If you use Dulon, do not use Plastikote primer and then Dulon top coat. The Dulon will not adhere well to the plastikote primer unless you use a tack cloth. But that can be difficult to do without screwing up the finish.

Enjoy.