Priming Question?

[maximumrpm]

Hi All

As most of you already know i pranged my car....ive almost fixed all the panels, but am tight for cash....i have sanded all the panels and want to prime then so it costs cheaper to paint....now heres the question...i want to prime in 2 pak, my front guards bumper and bonnet.....i have primed in acrylic before and its just miking the primer with thinners...whats involved with 2 pak??? and priming a fibre glass front bar in 2 pak is that ok, or do i have to put some flexi stuff in the primer so that is doesnt crack off...cheers

[maximumrpm]

any painters out there?

[maximumrpm]

come on ppl some one must know???? cheers

[frogman]

2 pak is paint or primer mixed with a hardner (then thinners between 5 to 20%)

They are VERY harmfull to breath in so you need a mask with proper filters & Its not really legal to spray 2 pak outside of a booth so you dont want to be doing it in your driveway where people can see you ( plus the overspray can travel a long way.

They come in 4lt tins with a seperetate hardner & you'll have to get reducer(thinners) & a measuring stick with the right ratios on it too, you would probably only use about 1.5lt though.

It might be worth taking the panels to your smash repairer and getting a price for the work before you go out & buy everything...

But if you are keen to do it yourself there are two types,

4:1 primer filler &

2:1 primer surfacer

If you have alot of repairs that arent super straight go for a 4:1 (4 parts primer to 1 part hardner) 'primer filler' these are generally thicker and fill scratch marks in bog work & give you more to work with when sanding. Usually put down 4 good coats, starting with just priming the repair & working your way out each coat allowing flash off time between coats.

The down side to these being thicker is that it is hard to do big panels (whole bonnets) if your arent quite good with a gun as you need to spray them a bit slower. If you have alot of repairs on the bonnet & need to prime the whole thing really well, i would suggest doing 2 coats over the repairs with 5% reducer then 2 coats over the whole thing with around 15% so you dont end up with dry lines going up & down.

If the bonnet is new or good 2nd hand & you only have small repairs then 3 coats of a primer surfacer should be fine. These dont have as much body to them, so they dont fill scratch marks or hide repairs as good. If the guards only have repairs up near the headlights, only rub & prime a far back as you have too, 10-15cm past the bog.

As for you're fibreglass bar, no you dont really need a flex agent.

I hope this helps you out.

[maximumrpm]

cheers thanks for all your help champ

the panels are straight so hopefully it will be easy...thanks again

should a flex agent be added to the paint for the front bar? as i dont want stress cracks...cheers

[frogman]

cheers thanks for all your help champ

the panels are straight so hopefully it will be easy...thanks again

should a flex agent be added to the paint for the front bar? as i dont want stress cracks...cheers

It cant hurt to add a flex agent to the paint, but fibreglass is a pretty stiff material, so when it comes to front bars that are prone to stones/driveways/speedhumps etc stress cracks are just a part of life really. Flex agents are more for the soft plastics, normal bars, mudflaps & those rubber type boot spoilers etc