Prep on plastics

K

Korey

Guest
I've been having trouble getting primer to stick to plastic helmets. I've watched every YouTube video available, tried doing everything that was suggested. Nothing has worked so far. Please help!!
 
Someone with more knowledge than I will likely be along shortly, in the meantime I suggest you head over to the Intro section https://www.airbrushforum.org/introductions/ and provide some basic info.... Our welcome Dragon has some suggestions on the info that will be most helpful in our guidance

76d29be6-b2b6-417c-9257-d194ae83eb90-jpeg.56198
 
As for your question here, i'm guessing the first questions you will be asked are:

What prep have you done so far
What brand of primer & sealer have you used
are you using any kind of bonding agent on the helmet to assist adhesion
Can you provide info on the type of plastic the helmet is constructed of . . . . .
 
As for your question here, i'm guessing the first questions you will be asked are:

What prep have you done so far
What brand of primer & sealer have you used
are you using any kind of bonding agent on the helmet to assist adhesion
Can you provide info on the type of plastic the helmet is constructed of . . . . .
Ditto
If not at least the model and brand of helmet.
 
I've gone over the entire helmet with the green scotch pads. Primer lifted after peeling back design to paint. Also tried sanding with 320grit then moved up to 600grit washed down with dawn soap and warm water. Left to dry over night with the same results.
I'm using a rustolum spry can primer made for plastics.
As far as the type of plastic, I have no idea. It's a 3m hard hat that can be purchased from any hardware store.
 
The one that is just called plastic primer.,..the one plastic it isn't for is polyethylene. Hardhats are usually hdpe. Except the fiberglass ones
I'd suggest rust oleum universal bonding primer, or an adhesion promoter like bulldog.
Flame treating is also highly beneficial for hdpe.
 
It's called 2x American accent primer. I have a friend that paints hockey helmets and he swears by it.
Just watched a video on YouTube on heat treatment on plastics. I'll try anything at this point.
 
Well, vinyl nitrile isn't polyethylene,
As you've found out....and 2x lists polyethylene as something it might not work on.
It's one of the worst to try and paint.
Flame and universal bonding primer are my go to for it.

Oh, and definitely skip the bulldog if the paint you use over top is an enamel...like in most spray cans.....the two aren't compatible.
 
I'll be using water based. I have createx wicked paints. I've had success painting on canvas, wood and metal so far but this helmet is kicking my ass! I've done this 3x's so far. I'm buying a new one and starting over tomorrow.
Question on the heat treat; do I scotch pad before heat or after?
 
I would think before, the flame treat makes an extremely thin layer of modified material Soo ..I think you'd just have to wash it good after scuffing and before flame treat...
 
Hmm, I may have to retract the bulldog part.
According to their 2008 TDS it's nit to be used in lexan or any polystyrenes

According to their 2018 TDS
8. Bulldog should not be used on Lexan® or polyethylene surfaces.

I know it works bc of the liquid styrene. Which doesn't work on polypropylene. Wasn't aware of the polyethylene thing.

Now they are recommending bulldog bft for the polypro/ polyethylene
Family....

Anyone used it on PE?
I use it on urethane bumpers but that's about all these days.
 
Last edited:
As for scuffing, I would use a red scotchbrite which is about 600 grit, dont go any finer than that. Make sure you give it a good wipe with wax and grease remover and also tack rag it to make sure there's no dust or bits on the surface.

Lee
 
Back
Top