smoothing interior plastic

what is the best method for smoothing interior plastic. What sandpaper to start and finish with, what primer to use and what else is needed. Thanks in advance for your help.

I'd start with prolly 80 or 180 and sand down as much as you can with out weakening the plastic, then spray adhesive plastic promoter before primer, spray a high build primer, so you can wet sand to 600 wet and the spray color and clear, and you should be done after that.  To wet sand and buff, would be difficult, try not to put the clear on to dry, I'd use medium-wet coats, to keep it somewhat even.

Use 180 grit. You can get a 100 pack of disc on ebay shipped for under $20.

Start low numbers and build your way up to 600 wet sanding. i think we did 80 120 220 400 600....not sure if the numbers are correct but you get the idea. I think we did the 80 and then sprayed with high build primmer a couple coats. start with 120 and sand in an X patern . Use blocks to sand not your hand or you will leave divits from your fingers. Just work your way up to 600 from there. try not to leave deep marks from the lower grade sand paper or you will sand through the primmer trying to get them out. in the end it should be very very smooth like glass almost.  Hope this helps

Edited: 7/6/2009 2:53:19 PM by low99maz

Just did my whole interior, I used 80 upto 320 then used a flexible elastic primer that had adhesion promoter in it (all spies & hecker supplies), then hi build about 3 wet heavy coats then wetsand 400-600-800 then base. Take your time sanding the raw plastic and get as much texture out as you can because you dont want to rely on the paint to fill the low spots. To much paint on your plastic is not a good thing. Have fun sanding plastic sux!   O yea make sure u clean the shit out of the plastic too! Hit it with a good plastic cleaning paste and a scotch brite pad before you start sanding and a couple times during the raw plastic sanding before any paint is applied it will help get all the chemicals(armor all) out of the plastic!

I started with 80(dry), then used 400(dry), then finished with 800, and 1000(wet)... I'm not an expert, but that's how I did mine...