I've decided to paint my supra and I tried on my front bumper but it didn't turn out as what I expected. I also tried on my gas tank cover and that seemed to turn out fine. Bumper is plastic, gas tank cover is metal. I sanded both down with 80grit then 180grit but the bumper turned out looking like ****. I started to paint anyways just thinking that the paint would get rid of the scratches and ****, but to no avail. I need to know what grit I should sand down to the bare aluminum and what grit to sand down plastic parts to just the bare plastic. I also would like to know about sanding in between coats, blah blah blah. Thanks alot in advance.

Quote: Originally Posted by AMD Daddy I've decided to paint my supra and I tried on my front bumper but it didn't turn out as what I expected. I also tried on my gas tank cover and that seemed to turn out fine. Bumper is plastic, gas tank cover is metal. I sanded both down with 80grit then 180grit but the bumper turned out looking like ****. I started to paint anyways just thinking that the paint would get rid of the scratches and ****, but to no avail. I need to know what grit I should sand down to the bare aluminum and what grit to sand down plastic parts to just the bare plastic. I also would like to know about sanding in between coats, blah blah blah. Thanks alot in advance.

First of all, grab a book about Auto Body painting, from the auto parts store, or a library, it will cover most of your questions.

It sounds like you forgot to Primer it too, that is how most scratches are filled in.

36 grit- Rough- bodywork, very course.
80 grit- Medium -heavy duty, good for removing paint, and shaping of bondo
120 grit- Medium- good for blending paint, feathering the leading edge of paint when there are multiple coats.
220 grit- Semi fine-I use this after the first coat of primer
360-400 grit- Fine- used for final prep of primer before paint.

Those approximate grits, as long as they are pretty close to those numbers, you should be OK

Anything finer than that (Like 600-2000) is used after painting to remove minor flaws before buffing with a machine for that mile deep look.

You also know you need to add a flex agent when painting plastic, other wise it will crack and peal

You can always catch me on MS IM if you have other questions

Didn't I give you a run through on Bondo last year?

Okay so if I am correct. Sand to around 200grit, prime first coat, sand to 200-220, prime 2 more coats, sand to 400grit, first coat of paint. and then after I am lost. I understand Bondo crystal clear now and i did alot of bondo and it turned out superb. Now whats this thing with flexi agent and whatnot for plastic? Do I paint bondo in the same way as I would metal or as I would plastic? Anyways to make the transision from the metal to the bondo go un-noticed? Can you help me figure out what I do after the first coat of paint after all the steps I listed, if they are even correct.

Make sure you rough up the parts you will be applying Bondo to with at least 120 or it will not stick well. Cut the filler down with 80 then feather filler out with 200-220 to get a nice smooth transition, but its unlikely it will be on your first tries you will have to feel around real good to get it smooth, the eyes dont work here. Then prime it with a good urethane primer with a flex agent. Sand the primer with 320 if using single stage enamel and 400 if using a base/clear system, with flex agent in either. Apply Bulldog adhesion promoter and apply paint as normal. You can skip the flex agent and Bulldog on the metal parts but it doesnt hurt.

OH, and if you buy Bondo brand filler, buy the blue can lightweight stuff, not the usual red/black can. It is much higher quality and easier to work with.

Do spraycan paints come with the flex agent in them? Can I get that bulldog stuff at canadian tire?

Quote: Originally Posted by AMD Daddy Do spraycan paints come with the flex agent in them? Can I get that bulldog stuff at canadian tire?

You gotta be joking. No way your painting a supra with bomb can unless its a model supra.

I doubt hes joking.......alot of people try to rattle can their car. Please post pictures when your done. -

So do you plan on spray painting the whole car, well good luck . post pics when your done. especially after you spend all that money on spray paint.

Well how bad could it turn out? I've been painted metal for quite some time. Plastic is another thing for me though, can't seem to get plastic painted too well. Its a 1981 Toyota Supra Celica L-Back with 281500KM on it and a paintjob that was well taken care of besides the occasional rust-spot here and there but its very dull looking. How bad could the ol' rattlecan be if I take my time?

Quote: Originally Posted by AMD Daddy Well how bad could it turn out? I've been painted metal for quite some time. Plastic is another thing for me though, can't seem to get plastic painted too well. Its a 1981 Toyota Supra Celica L-Back with 281500KM on it and a paintjob that was well taken care of besides the occasional rust-spot here and there but its very dull looking. How bad could the ol' rattlecan be if I take my time?

OH its an '81 I guess thats not so bad. But you know if your painting the whole thing it gonna cost you a bundle. You could go to a Maaco or Earl Scheib and have it done semi-professionally for around $200, well with Maaco anyway, I wouldnt say Scheib qualifies as semi-pro. Most Maaco's will do a nice job if you either prep it well yourself or pay them to do it. For $200 all you get is a scuff and shoot, but if you get the body strait and prep it well yourself it will look good for a $200 paint job.