Hi there

I'm trying to paint these side markers since it is cheaper for me to paint than buy them when converted in my Canadian currency, plus the shipping. And I like to DIY and learn new stuff so I figured let's do it! Unfortunately it hasn't gone as planned.

So I started of sanding down the piece with 80 grit, then wetsand 320. [url]Looks like this https://i.imgur.com/Ytp9MHh.jpg . Then clean with wax grease remover and swipe with a tack cloth and apply my adhesion promoter. https://i.imgur.com/Stzx0GZ.jpg . Then apply the primer. https://i.imgur.com/w32v0Wv.jpg . My piece then looks like this. https://i.imgur.com/FpeWezM.jpg . Then when I got to wipe with WGR or wetsand it's coming of as you can see. https://i.imgur.com/8D4gFWj.jpg

What is happening and why is this happening? Am I missing something in my steps?

myself i wouldnt use WAG on the primer-just sand,which looks like you sanded through the primer.
80 to 320 grit is a massive jump. that piece shouldnt need coarser than 320-400.

tomsteve wrote:myself i wouldnt use WAG on the primer-just sand,which looks like you sanded through the primer.
80 to 320 grit is a massive jump. that piece shouldnt need coarser than 320-400.

So, what do you recommend I do

I agree with Tom the primer is coming off because your sanding it off I would never use anything coarser than 220 and that would be for a real rough piece. 400 should be fine for your project. that shaker can primer isn't going to build much. so if you wanting a smooth finish you may want to spray 3-4 coats then wet sand with 400 trying not to sand though like you did. if you do no big deal spray a few more coats and sand with 600-800 with water.
Jay D.

badsix wrote:I agree with Tom the primer is coming off because your sanding it off I would never use anything coarser than 220 and that would be for a real rough piece. 400 should be fine for your project. that shaker can primer isn't going to build much. so if you wanting a smooth finish you may want to spray 3-4 coats then wet sand with 400 trying not to sand though like you did. if you do no big deal spray a few more coats and sand with 600-800 with water.
Jay D.

Sorry fellas I wasn't to clear. The 80 and 320 grit was just for prepping the piece. When I sand the primer to make it smooth it's with 600 grit wetsanding.

I've just tried doing adhesion promoter and right to basecoat then clear coat and it never stick. I could wipe it off with my **** finger. Something musn't be right here... I'm trying to lay on like 6 coat of primer now to see if that works. If not idk what to do... I hope my painted reflectors aren't gonna cost times 2... ( Bought the DIY stuff to avoid paying the pre painted ones lol).

Should I maybe put some body filler like a thin coat of it?

More primer isn't going to work if, as you say, the problem is the bond with the plastic. You're just building a bigger house on sand.

Hard plastics like that don't usually cause a problem. Take it all off, Prepsol and then give each face a light wipe with a cloth lightly soaked in thinners. tack and spray the AP.

AP needs just a single light coat and should be allowed to flash completely - say 20-30 minutes at 20C. Apply primer with light coats, allowing each coat around 15 minutes to flash and the final coat an hour or so before wet sanding prior to base.

The prep you've done is ok so I'm leaning towards the bottom layers still being wet as the cause of your problem. The spray can AP tends to be a bit hit and miss - quite different to the stuff used in a spray gun.