12 replies to this topic

[conlad]

Going to halfrauds in an hour so need an answer swift!

Sanded back front bumper with 240 dry all over, gonna fill all cracks/holes with isopon p38, then sand back - then prime!

But, what primer is needed for this? Read up on some tpoics on here but all say different!

Etch apparently eats into the fibreglass and then 2k is too thick!

Ahhhhhhhhhhhhhhhhhhhhhhh! Someone just give me a definitive answer please ( it will hten be painted with a memtalic paint by the way)

Cheers conor

[crazypainter]

I always use etch

[conlad]

Works fine on fibreglass then? good adhesion for the primer to stick to?

[crazypainter]

Yes, u need good quality etch or wash primer, and prep has to be good for adhesion

[minimartin1]

Worked in trade for 8 years and we always used 2k. No point using etch as its for bare metal to help prevent rust so total waste of time. 2k gives you the build you need to flat back and hide any blemishes in the fibreglass

[crazypainter]

Good point but silicon is used to release fibre glass from the mold, etch properties as u say are for bare metal but the adhesion properties of it trasfers to fibre glass. I've been in the trade most my life doing paint work on race and rally cars n etch is the way forward, when I used 2k on its own the results weren't as good as when etch is used 1st. Ur choice at the end of the day dude.

[panelbeaterpeter]

Probably a bit late, but plastic primer works well, you just need an adhesion promoter. I know loads of people who use etch on FG and plastics, but I'm not convinced.

[midridge2]

Dupli-Color^® Self-Etching Primer etches and primes bare metal in one step, making it ideal to use as the first step in all automotive priming projects and for use on spot repairs. A high-quality formulation allows for maximum adhesion under all types of automotive finishes on plastics, fiberglass, bare steel, aluminum and stainless steel surfaces
taken from dupli-color web site but after looking at other big paint makers eg max meyer, standox etc, none of them mention using it on fg.

the original poster was asking about getting primer from halfords so that rules out 2k .

[Surfbluegarage]

ive always used etch first then a god high build after to get rid of the weave but thats just how ive been taught.

[conlad]

cheers for all the replies and advice, greatly appreciated....

ive always used etch first then a god high build after to get rid of the weave but thats just how ive been taught.

would others recommended this too or simply whack on etch then spray?

[djdobson]

i found that just using a high build plastic primer works perfectly, if using aerosol i always use U-Pol high build primer. it the one in the blue can lol

[j-b_2009]

ive just used some of the cheap 2k off of the bay... surprised at how well it covers, did the whole car with 2.5L

[minimartin1]

I would just hi build it then flat it back. Thing with fibreglass is its never straight so the more u can flat back the better as u get it straighter