Help restoring dead paint

[idickers]

I've just picked up a 1991 BMW 318is, which has its original silver metallic paint that has been well and truly beat. The paint is oxidized and the clearcoat has scratches. I plan to fix the mechanicals and some rust over the next year, and then repaint the car myself. However, I thought the current paint would be good to learn some polishing/sanding techniques prior to working on new paint.

What is the best method to attack an old finish? I have in my garage a Dewalt DW847 7" rotary polisher (0-1750 rpm), a Porter Cable 7336SP random orbital polisher, and a lot of interest on my part, but very little practical knowledge. Is this something that is best started with wet sanding, or can I start with a buffing compound?
Thanks for any suggestions,
Ian

[style]

I've just picked up a 1991 BMW 318is, which has its original silver metallic paint that has been well and truly beat. The paint is oxidized and the clearcoat has scratches. I plan to fix the mechanicals and some rust over the next year, and then repaint the car myself. However, I thought the current paint would be good to learn some polishing/sanding techniques prior to working on new paint.

What is the best method to attack an old finish? I have in my garage a Dewalt DW847 7" rotary polisher (0-1750 rpm), a Porter Cable 7336SP random orbital polisher, and a lot of interest on my part, but very little practical knowledge. Is this something that is best started with wet sanding, or can I start with a buffing compound?
Thanks for any suggestions,
Ian

Go pick up some 1500 and some compound and try leveling the paint with 1500 wet with share block then Polish out the scratches with a wool pad and compound once you can get the scratch out perfect then hit it with a black foam and the same compound then once you have that all down pick up some sure finish and you'll be set..

[tomsteve]

i would suggest that before doing anything,wash it good, then clay it. some pics would help determine the best coarse of action to take.

[idickers]

For wet sanding I think I'm going to get an Airvantage sander. For buffing, would I be better off (as a beginner) using the random orbital polisher, or the rotary?

[Len]

For wet sanding I think I'm going to get an Airvantage sander. For buffing, would I be better off (as a beginner) using the random orbital polisher, or the rotary?

Get a decent variable speed rotary, it's the only way you're going to make any progress in a reasonable length of time. If you're scared of damaging the paint you can slow the rotation.

[idickers]

My Dewalt is variable speed (0-1750 rpm), will that do?

[Len]

My Dewalt is variable speed (0-1750 rpm), will that do?

Yes, that will probably be fine. Get the right backing plate, pads and compound if you don't already have them.

LINK

[idickers]

Here are some pics of the paint. I can't feel the scratches when I run my fingers over them. It looks like the previous owner never waxed the car, and washed the car with a scotchbrite pad.
Ian
Paint_09 copy.jpgPaint_12 copy.jpg

[idickers]

I bought some Sure Finish, the set of Sure Finish polishing pads,and Robert's "Detailing for Enthusiasts" DVD. From watching Robert's video, it looks like I should start out using Sure Finish on a wool pad on the rotary polisher to remove scratches, and then switch to a foam pad on my random orbital polisher to remove swirls.

The polishing pad kit comes with two wool pads, a high density and a loose, and with two foam pads, black and orange. How should I decide which wool pad to use, and then which foam pad to follow-up with?

[Len]

I bought some Sure Finish, the set of Sure Finish polishing pads,and Robert's "Detailing for Enthusiasts" DVD. From watching Robert's video, it looks like I should start out using Sure Finish on a wool pad on the rotary polisher to remove scratches, and then switch to a foam pad on my random orbital polisher to remove swirls.

The polishing pad kit comes with two wool pads, a high density and a loose, and with two foam pads, black and orange. How should I decide which wool pad to use, and then which foam pad to follow-up with?

Just about any standard wool pad will work and I'm a big fan of the orange foam pad for almost any application. The problem I see when looking at the picture is that the clear has "crazed" (cracked) and I doubt that you're going to be able to remove a lot of the damage by buffing but you may be able to get rid of some of the cracks by sanding and polishing.

[idickers]

Thanks for the quick help. I'd like to work on this over the weekend, and don't have an air sander. Can I pick up some sandpaper form a local auto paint supplier and use my random orbital polisher/sander, or should I do this by hand?

[Len]

Thanks for the quick help. I'd like to work on this over the weekend, and don't have an air sander. Can I pick up some sandpaper form a local auto paint supplier and use my random orbital polisher/sander, or should I do this by hand?

I'd recommend picking up some 1500 or 2000 grit wet sanding paper and doing it by hand. You can get "Job Packs" of 3M sandpaper with 5 sheets of paper. Put a couple sheets in a bucked of water and let them soak about 15 or more minutes before you use them. Sand a small 2 square foot area then polish it to test your result before sanding the entire car, you may find that it won't help enough to make it worthwhile.

3mjobpack3a.jpg
Job Pack Link

3m5526.jpg
Link

[Henry]

Thanks for the quick help. I'd like to work on this over the weekend, and don't have an air sander. Can I pick up some sandpaper form a local auto paint supplier and use my random orbital polisher/sander, or should I do this by hand?

OEM paint does not allow for very much sanding at all let alone paint from 1991. Below is a LINK to Robert doing a sand and buff on OEM paint and remember, Robert is a highly skilled professional in doing this. I would guess you will go right through your clear into the silver and have a mess because of sanding. ROBERT'S EFFORTS:

http://www.autobodystore.com/rsw.shtml

This link comes from the CLASSROOM which can be found from the HOME page at the top left of any page you are on. You will find tons of information there.

Henry

edit added: It's important that you "season" the wool pad with a little water and product. Don't hit that old paint with a dry wool pad. I prefer Robert's ORANGE pad.

[TOGWT]

A question before you wet-sand or compound/polish the paint surface-

What paint thickness do you have to work with?

[idickers]

I'm not sure. How would I tell? I'm pretty sure it's 20 year-old original paint, that didn't receive much care.