Prep prior to painting

[reedx]

A very basic (and hopefully quick) question.

We're about to start painting the chassis parts and running gear on a 1/5th scale steam lorry we've been working on for the last few years. I wanted to make sure our prep method will be adequate as I'm not wanting to have to take it back apart to redo.

The parts have been mostly fabricated out of whatever scrap we could find lying around, so varying qualities of steel right down to black bar.

They will all be brush painted. The plan is to key them with emery paper or a wire brush. Clean with panel wipe. Grey epoxy mastic paint (from rust.co.uk) the bare metal as a primer/undercoat, then the following day paint with machine enamel in our finish colour.

Any gotchas in the above plan, or suggestions for improvement?

Colin

 

[steveo3002]

be aware the mastic doesnt brush on that nicely at all

so sand between coats to keep it smooth

 

[brightspark]

i may be wrong but i wouldnt have thought an enamel paint would coat over a mastic chassis paint ??? anyone

 

[Chipper]

99% sure that stuff is a Jotun epoxy in a different frock... so is an epoxy primer. In which case it'll want keying, and as said, won't brush too nicely. But should take enamel OK.

 

[steveo3002]

yeah epoxy mastic takes almost any top coat

 

[reedx]

Thanks guys. This is the epoxy mastic paint we've got

Epoxy Mastic 121

though I now notice they do a dedicated epoxy primer

Custom Epoxy 421

Is there any advantage in using this, other than the sightly cheaper price per litre?

We will definitely sand between coats. If it's like you say and doesn't brush on too nicely then enamel paint on top will make it look worse. There is a thinner included in the epoxy mastic pack to use with smaller items so we may do a bit of an experiment to see if it helps us. Saying that my father-in-law tried some of the machine enamel the other day and wasn't impressed with the finish - I think he now wants to use the same colour, but in Tekaloid instead.

I'll have a look at the Jotun epoxy, as mentioned by Chipper, it may be a bit cheaper than the £35/litre delivered the rust.co.uk product ends up costing.

Colin