Paint Bonding

NightWeasel

Young Tutorling
Hey guys. Relatively new to the airbrushing world. I started airbrushing motorcycle and flight helmets here recently and I really enjoy it. They look great. Everything seems to be working really well except for the paint that I’m using doesn’t like to stick to the surface very well. After it dries, it looks fantastic but as soon as I put a stencil on top of it and remove the stencil, even though it is a little stick stencil very often, the paint pulls off of the surface. Does anybody have any experience with this? That could lend me a hand? Thank you in advance.
 
A little more info. I have used both acrylic and urethane’s. Both seem to peel off at about the same rate. The surface of the helmets are all sanded with 600 grit, cleaned and dust free. It’s really disheartening when I get the helmet done exactly how I would like it, go to add some texture, and some shading with the stencil and the stencil rips off 3/4 of the area that it was stuck to.
 
Hello,

I am by no means an expert but a few things come to mind:
-Are you using primer? I think an appropriate surface primer will make paint stick better. Of course the primer will depend on the paint used.
-Is the surface really clean? Any chance there is any residue like any oil or wax? After sanding, you can clean with alcohol pads to ensure it is really clean.
-Is the paint you are using the correct type for the application? If it is going to be exposed to the elements like a helmet, the paint has to be durable like enamels or lacquers and will most likely require a clearcoat for protection.

Thanks,
Ismael
 
Hello,

I am by no means an expert but a few things come to mind:
-Are you using primer? I think an appropriate surface primer will make paint stick better. Of course the primer will depend on the paint used.
-Is the surface really clean? Any chance there is any residue like any oil or wax? After sanding, you can clean with alcohol pads to ensure it is really clean.
-Is the paint you are using the correct type for the application? If it is going to be exposed to the elements like a helmet, the paint has to be durable like enamels or lacquers and will most likely require a clearcoat for protection.

Thanks,
Ismael
Appreciate the response! Yeah it’s over sanded 2k clear coat. I paint then clear it assuming I can get the airbrushing done without it coming off with stencil or masking tape usage….
 
Hello,

I think that's your problem. Painting over 2K clear is usually a no-no. Even if sanded. If possible, airbrush your design over the base coat and then seal everything with clear.

Thanks,
Ismael
 
I painted a hard hat and ran into the same issue. I use lacquer. I found that a product called Adhesion Promoter that works for me. Spray it after sanding before the primer coat.

I have no experience with 2K clear so I can't offer any advice there. Personally I'd only use clear as the last step in the process. Any custom work would be done before the clear coat was applied.
 
How are you prepping the surface? sanding, wax and grease remover , You have to give the paitn a good tooth to bind to other wise it will peel off.
 
How are you prepping the surface? sanding, wax and grease remover , You have to give the paitn a good tooth to bind to other wise it will peel off.
Sir! Hey I’m sanding down to a 600 grit. Washing with a light soap and water. Usually finish it off with a 3M window cleaner
 
Window cleaner is not wax and grease remover. It can leave an unwanted film on the surface.
If it is not made for painting don't use it for painting ..
I never use soap and water on a hard surface I am painting , That was beat into my head back in the 60's
 
Don't think it's underground.
Although I agree that painting over a primer is always better.
The question is how sticky is your mask?
Is it frisk film, yellow mask, vinyl or something else?
How long did you wait for masking?
How long was the mask on before you removed it?
 
Painting over polymers is a pain in the backside due to all the differing types
Polyethylene is all but impossible to paint where as it close cussin polypropylene with the right primer that changes it's Dyne and leaves a hydrogen rich bonding sites is a breese.
The latest technology are silane based primers for polyolfins and some of the polyester based polymers like urathanes, polycarbonate.
Most of them only require a through mist coat as they are designed to create more hydrogen bonding sites. Not an interface layer. Once coated the clock starts and most only last no more than 6 to no more than 24 hours befor surface reversion to its previous state.
There is an older type called CPO chlorinated polyolfens I prefer these. Layer thickness seems less critical and I have had better outcomes on various plastic surfaces
A sanded surface helps, wiping with isopropal alchol with a clean lint free cloth a technique of rolling your hand so you are not spreading contaminates across the surface helps too. Especially when silicone lubes or release agents are an issue with polycarbonate and polyester resins like bike helmets . A water bead test on the substrate pirior and after sanding is a great help to tell you wether you need a primer.
Good luck
 
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