what did i do wrong?

[rockbound]

ok so i tried to paint my newbright jeep body. i sanded it all down, primed it with tamiya primer and then painted it with tamiya paint for plastics! but the paint is pealing right off! what did i do wrong how can i fix it?



Primed

painted



[img=http://img153.imageshack.us/img153/8665/dsc08669mv6.jpg]


ok some minor updates. here are the pics of the fenders painted and the paint peeling from removing the tape!! ARGHHHH.

[JasonC]

Is it the paint coming off, or the primer? Looks like the primer did not adhere to the plastic.

Did you wash/clean the body after sanding it to get all contaminents off of the body?

[obijuan]

what grit sandpaper did you use? it doesnt even look sanded. also did you peel it off with the masking tape when you painted the black?

[2JSC]

Tray painting it with something like Krylon Fusion.

[rockbound]

i used 320 grit sand paper, and yes the primer is peeling from the body, the paint adhered to the primer but the primer did not adhere to the body.

I used denatured alcohol after sanding to clean the body.

It peeled when i removed the blue paint masking tape from painting the flares,

[obijuan]

use around a 180-200 grit or so. 320 is too fine IMO.

[extreme]

it depends on what sort of plastic they made the bodys out of, try the krylon fusion if that doenst work you might want to try an adhesion promoter form one of the autobody supply stores if that doesnt work then go with a 2 part epoxy primer

if all else fails bake the body to release the solvents wash with hot soap and water and then prime with the best sticking stuff you can find

let me know how it goes i know these nylint bodys can be a pain

[joe_and_jeep]

I used the $1 Dollar Store paint without sanding my New Bright body and I never had a problem. And I put mine thru some abuse. I just made sure I washed it extremely well with dish soap and hot water.

[team3six]

First of all was the use of Primer! There isnt any need for it! Its a plastic paint and it bonds to the pores of the plastic. there was never a need to invest in Tamiya's paint though I had no idea they had plastic paint. I thought it was lexan paint. Ill have to check this out. But anyways. Rustoleum makes hundreds of colors and they have paint that comes in a full can for less then that tamiya paint could cost.

Im not picking on ya at all. My thought would be to take it all off with some denetured alcohol and re sand it. DONT prime it and paint it with good old regular Plastic paint. You should have no problem!

[O.C.D.]

Been using Tamiya plastic paint for years and have learned a few things about it. Tamiya has bad batches of paint, plain and simple. I have bought probably 50-60 cans of TS from them and the same color paint code will have issues. It is also sensitive to temperature. You need to put the can in warm water for a few moments to get the propellant working properly. I have used Fine White Primer on more than just plastic. It is an outstanding primer for plastic, but for your case I am shocked. If properly cleaned and lightly sanded that primer should no come off at all. Hell, I have soaked bodies in 90% alcohol for a month and it won't even eat through the primer. If the body is injection molded then there could be residual release agent in the plastic? But since you sanded it down and cleaned it I am at a loss. Fusion works great for plastic too. I use it on my Jeep fenders and it is flexible and last a good while. As mentioned, maybe you should try that?!

[Knoc]

^I agree. There is no need to prime it when its plastic. Primer is a sealer for BARE metal. Even seeing people primer there cars (1:1's) over there old sanded paint always made me snicker..
But yeah, Id strip er down, wash it real good with a degreasing soap (Like dish soap) and then spray it with some plastics paint. Then ya should be good to go.

[tjb]

Regular palstic paint don't adhere well to that kind of plastic no matter primed/sanded or not. You will have to use Krylon Fusion to get it to stick decent.

You will have to strip it down, use 400 or 600 wet sandpaper then wipe it down with denatured alcohol and shoot it with fusion. they make it in a yellow that matches what you have now also. It sucks, but is about the best/only real option you have...

[Hotflashjr]

The primer was the issue. I have had this before on plastic. Try using Testors model paints in the spray can or airbrush them on. I have found these work really really well. Duplicolor also makes a spray on adhesion promoter for plastics that I use a lot. It works really well. Make sure you was the body with warm water and liquid dish soap before paint. Any grease, finger prints will keep the paint from stick. If you do mask something off, run a razor blade along the paint edge very lightly before you peel the tape. This will any paint that adhered to the tape and keep it from peeling.

[rockbound]

thanks guys all good info to think about when i redo her.

Originally Posted by Doc J33P

Been using Tamiya plastic paint for years and have learned a few things about it. Tamiya has bad batches of paint, plain and simple. I have bought probably 50-60 cans of TS from them and the same color paint code will have issues. It is also sensitive to temperature. You need to put the can in warm water for a few moments to get the propellant working properly. I have used Fine White Primer on more than just plastic. It is an outstanding primer for plastic, but for your case I am shocked. If properly cleaned and lightly sanded that primer should no come off at all. Hell, I have soaked bodies in 90% alcohol for a month and it won't even eat through the primer. If the body is injection molded then there could be residual release agent in the plastic? But since you sanded it down and cleaned it I am at a loss. Fusion works great for plastic too. I use it on my Jeep fenders and it is flexible and last a good while. As mentioned, maybe you should try that?!

i think the temp thing may be what got me. i was painting this in my basement where it wasn't very warm. the cans and body sat overnight and half a day before i painted. temp was prob between 40-50 degrees at night and then about 50-60 when i painted. I always work in the basement cause thats where my area is so the temp is always low. when i repaint it i will do it in the summer maybe outside to warm everything up and use the fusion paint no primer.

o-well live and learn, that was really my first paint experience with plastics, i usually build tubers.

[run2jeepn]

Next time go to Wal-Mart and head towards the Automotive Paint section. There is a spray can Call BullDog. This stuff works good on small projects. Also pick up some wax Cloths. After sanding it all down. Blow it off and take the Wax cloth and wipe it clean. The wax cloth will remove all dirt and everything less from the body.

[rockbound]

man i asked a bunch of people at retail and hobby stores if they made anything like that and they all told me no!!
this board truly is amazing!! so much great info and advise! thanks everyone!!

[pantablo]

I used Rustolium on my hardbodies and its holding up to abuse just fine. No primer. very little or no prep.

[extreme]

if i dont have the body in my hands i really cant tell you what sort of method to use toget the paint to stick.

my buddy used tamiya paints and it wrinkled like an old man in a bathtub when he tryed to clear it and it never stuck to well

id try the bulldog adhesion promotor but soemtimes that will leave a nasty texture that needs to be blocked down again

try the fusion that will be your best bet, no primer since it doesnt require it.

let that set up over night and run a finger nail along it and see if it comes off if not then you should be good to go

i've delt withthis problem plenty of times! tamiya's hard bodys can actually have an issue when you sand them down alot and require the bulldog AP. i havnt been too succesfull with the fusion but thats b/c i dont use it too much

temp really shouldnt be that big of an issue your only a couple degrees off from the the required temp and the only issue you should have with that is dry times not adhesion

[gregsgrafx]

all molded plastic bodies should be washed with warm water and mild dish soap prior to sanding to remove any mold release film. this will avoid sanding film into plastic.wash again after prep and handle body with powder free latex gloves.as for the masking tape pealing the paint, i use automotive fine line tape for the edge and back mask with 3m green tape.let paint dry 24 hours. when you peel tape, try to pull it off strait back against itself to help cut paint. hope this helps and good luck!!!

[gregsgrafx]

all molded plastic bodies should be washed with warm water and mild dish soap prior to sanding to remove any mold release film. this will avoid sanding film into plastic.wash again after prep and handle body with powder free latex gloves.as for the masking tape pealing the paint, i use automotive fine line tape for the edge and back mask with 3m green tape.let paint dry 24 hours. when you peel tape, try to pull it off strait back against itself to help cut paint. hope this helps and good luck!!!