Body work and paint prep, oh noes.
 

I am going to be doing some much needed body work on the Miata very soon, eventually ending up with new paint and new rear rocker panels. I have done stuff in the past, but I never really did it right, so it has always turned out "average" at best.

First off, is bondo typically a no-no? I want to fill the body contours, I have seen it before and absolutely love the look. I think I can get away with bondo on the metal parts, but would I have to use some kind of resin or fiberglass for the front and rear bumpers since they flex? Or should I ditch the idea of bondo entirely and use something else on the metal panels?

And second, I used to have a friend do most of my painting and he always told me it was OK to use rattle can primer to prep it for him. If I use a decent brand primer from a can, will that cut it? I used cheap primer on my engine bay along with cheap paint, finishing it with Omni clear coat, but the paint and primer are so "soft" that if I drop any bolts or nuts it chips off right down to the original paint. I would hate for my exterior paint to be that fragile, I would trash it in a year for sure.

As always, any input is greatly appreciated. :)

Paging Leatherface.
__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

I'm actually using bondo to fill the body contours on my car right now.
Here's a link to my project....MX-5 Ireland :: View topic - The BIG Project.

(PS) I was going to create a thread here when it was all done.

Thanks for the link, bookmarked. Let me know if you run into any problems with that bondo.

Shouldn't be any probs, another member of our club here in Ireland has already done his car and it's perfect !

regular bondo brand filler is absolute shit. Find a paint supply store near you and get some good stuff. to fill in the body line it's best to A) weld some steel in it first then filler B) use a fiberglass reinforced filler also known as "kitty hair" and then finish with a suitable light weight filler. C) as a last resort use bondo, but be prepared to do it again in a couple of years when it shrinks. that body line is just to deep to be filled with crap filler.

You can use rattle can primer, just check with your painter to see if it's compatable with the type of paint being sprayed. of course real primer from a gun will net better results.

the body line on the bumper is best left alone, unless you switch to aftermarket bumpers that are fiberglass. in that case you'd want to use fiberglass mat and resin. the plastic bumpers never last or turn out good with anything more than the paper thinest of layers of filler.

hope this helps.

when it comes to body work do it nice or do it twice.

Ops typo, I'm using a polly"something" filler.

I was thinking that it might help to weld in a small rod of steel into and along the body line in the center of the groove to give the filler something to grab onto? I'm talking a bunch of tack welds.

Now that I think about it, I haven't seen stock bumpers filled, only fiberglass bumpers. That makes sense now.. Darn

My new IL Motorsports front bumper is fiberglass.
The guy who already has his done just used filler all around the car, but his front bumper is from an Mr2 which was cut to fit onto a miata, I don't think that it's fiberglass though. His rear bumper is standard Mazda stuff, it all still looks perfect.
I'm gonna try it out anyway, if it doesn't work I can always redo it since I'll be repainting the car this summer and I know a welder if I need a metal strip put in.
If the bumpers are plastic why not fill them with MORE plastic ? It would sand down perfect and 'flex' with the original bumper etc. Lots of liquid/gel plastics out there to mix up and use.
I'm sticking with the polly"something" filler since I've already seen it done on two cars here in Ireland and they are both perfect after about four years in Irish crap weather.

(PS) Ireland doesn't get more than 28C in summer...22C if we're bloody lucky, maybe that may be an issue in the USA ? Come to think about it, it started raining here last June and didn't fecking stop until mid September....Jazus I need a holiday.

uhg good luck filling the body line. i did it in my 240 and it was a pain. Kitty hair is a must! dont go throwing bondo in there like its your job. Metal would be the best tho.

Ive painted a few cars and a shitload of little stuff, its a learning experience to say the least. As for the rattle can primmer... i used self etch rattle can here and there for bare metal spots, but overall i wouldnt. You NEED to use a good highbuild primmer, and a sealer in my opinion is a must. Im working on doing a DIY writeup on the paint process on my local uconn car club forum... when its done ill post a link up here. Im no expert, just sharing my experience.

your going to be rolling on tremclad right :)

So what is this "filling the body lines" business all about?

Do it. There are never to many DIY writeups for real projects.

<--- doing bodywork entirely too soon.

people use filler all the time, even on high end paint jobs. Just don't use bondo, do some research on what fillers are good. Also, if you want your car to look straight, get at least a 1 foot sanding board for straightening out waves and make sure you understand what a "guide coat" is and how to use it. If you dont mind some light waves in your pannels, then a 3m rubber sanding block would do fine.

some advise I got from a really good painter: DONT use cheap bondo. DONT cheap out on the primer as well. He usually fills whatever (assuming its not more than 3/16ths of filler you're actually using. any more is a no no) with filler, grinds it down with really rough sandpaper (100-240) to get it to the right shape/etc...Then he uses this really expensive/good primer that he buys by the quart and sprays it with a gun. he told me to NEVER use rattlecan shit. the stuff he uses COMPLETELY fills in all scratches/blemishes and really does a good job. hits it a couple times with 400 then 600 and its ready for paint.

He is a very well known painter here in sacramento, so I usually pay close attention to his advise. Dont really know much myself though, so this is just my .02

This stuff covers up filler sand scratches. That way you dont have to spend so much time sanding from 100 - 180 - 240. And for me whenever i try that method, i always miss a few spots and then i get pissed off. My only gripe with it has a tendency to not lay perfectly flat and its harder to sand than regular filler

http://www.evercoat.com/imgs/product...llon%20711.jpg

I think a good quality primer (not rattlecan shit) will do the best scratch filling you can possibly think of. With the stuff available nowadays, you really dont need that huge ass 100-160-240-320-400-600 transition. good quality filler+160+good quality primer+400/600= good to paint

you are probably right, i guess i made my life harder when i did my paint prep work

man, I have so much fucking prep ahead of me its ridiculous. the whole car, while fine from 10 feet away, has 100000s of tiny ass little dents and dings I will have to remove this spring/summer before I paint it. :mad:
I feel your guys' pain

+1 on the big job ahead. Im getting ready to paint mine, using the shop and help of a freind of my father, since I live in a bad area for painting stuff. I have so many little dings and scratches on my car. Pretty much going to have to go panel by panel and do some serious prep work. Looking forward to new paint, not looking forward to the work. Almost makes paying someone worth it.