Question about filler

[JFortner5]

I bought some Bondo glazing putty earlier today to fill a few seems on my 86 NASCAR Monte Carlo. My question is should I apply the filler directly to the plastic or prime it first? Does it even matter? This is just the basic putty it's not the two part. I wanted two part but couldn't find it. I think I'll be ok though these are really small areas I'm working with.

Thanks,

Joey

Edited January 21, 2013 by JFortner5

[JFortner5]

I just realized there is a Q&A section, sorry I posted this here.

[BKcustoms]

It sticks really well to bare plastic, just make sure to apply it as thin as possible. It has a tendency to shrink up a lot when it's put on thick.

[JFortner5]

Thanks I was hoping it would. It's too cold to spray anything in the garage tonight. But at least I can smooth it up a little.

Thanks again,

Joey

[Ace-Garageguy]

The one-part glazing putty is basically thickened lacquer primer. The solvent that makes it stick to plastic is simply lacquer thinner mixed in with the solids, just not as much thinner as there would be in 'primer'. Thin coats is right, and it's a REALLY good idea to scrub your model with hot water, Comet and an old toothbrush before filling low spots (to remove possible tooling lubricant contamination that can play jell with adhesion). I personally recommend scuff-sanding the spots first, too.