d-9 0 Posted February 28, 2006 After carefully following the instructions on the tin right up to the "leave for 24hours to harden prior to rubbing down" I started rubbing down with wet and dry, and all the frigging primer washd off Share this post Link to post Share on other sites
Jonmurgie 2 Posted February 28, 2006 What are you painting? Share this post Link to post Share on other sites
C_W 3 1 Cars Posted February 28, 2006 Are you sure it's water based? I If its out of a can then surely it can't be? I find that that primer sands very quickly and if you're using wet n dry will look like its dissolving in the water and you can sand right through it if you're not using a very fine grade. Share this post Link to post Share on other sites
ashley peddle 3 Posted February 28, 2006 seriously doug stop p*ssing about with the rattle cans and stick them in a box and post them to me - il give them back to you at haynes donut Share this post Link to post Share on other sites
d-9 0 Posted February 28, 2006 nooo I WILL learn to do this myself! thanks for the offer thou mate! turns out maybe i was rubbing a bit hard, or maybe 1500grit wasnt fine enough :S Share this post Link to post Share on other sites
ashley peddle 3 Posted February 28, 2006 was this black plastic by any chance? if it was then you need to sand it back quite a bit to get rid of years worth of 'back to black'... paint dont like that stuff Share this post Link to post Share on other sites
d-9 0 Posted February 28, 2006 nah theyre the body colour covers on my wing mirrors. except the mirrors are off a green saxo! Share this post Link to post Share on other sites
Paintguy 0 Posted February 28, 2006 (edited) It's definately not water based, but I think you've worked that out now Ashley's spot on with his last comment though. Almost every adhesion failure I've seen on plastic is down to improper cleaning before applying primer. Even brand new plastic parts need a thorough clean, as they are covered relase agents to stop them sticking in the moulds when maufactured. Plenty of hot soapy water, using a scrubbing brush if it's textured, followed by clean water, then a solvent like white spirit (or better still a proper degreaser) should be your minimum. Edited February 28, 2006 by Paintguy Share this post Link to post Share on other sites
Guest smokinslim Posted March 1, 2006 I had the same problem a few years back with a boot spoiler from a citroen xm. Sanded the spoiler to remove laquer and key for new paint, paint was a bit thin in a few places and went straight down to bare spoiler material (whatever it was made of). Off i went down to halfords for primer, type chosen on their recommendation. Primed the whole thing in the end, and left for at least 24hrs. When it came to a light sand before painting proper, i may as well have washed the primer off! I've never had problems like this when using primer on metal tho. Didn't bother getting any more primer for it, jus slapped the paint straight on and it stayed. Share this post Link to post Share on other sites
Paintguy 0 Posted March 1, 2006 As hinted at by C W, most plastic primers just don't have the build (thickness) of regular primers, but are formulated more for adhesion. If you want any sort of depth for sanding or levelling something out, you'd be much better off using a coat or two of plastic primer, followed by a regular primer or primer-surfacer. Share this post Link to post Share on other sites
