Need help and advice - Painting a 1986 911 Targa

vulcan300 · 09:46 PM

I bought my 86 a few years ago and knew at the time that I'd paint it at some point as the paint was pretty awful. It has stone chips galore on the bumper; the paint is completely crazed and cracked on the passenger quarter panel, flag mirrors, and all around the windshield; and the panels seem to all have slightly different colors and levels of gloss. In short, it's a mess.

I thought I'd have someone paint it but since I have access to a full shop, paint booth and many of the tools required to do a high quality job I want to do the work myself. To get ready I've read Freddy Hernandez's 101 series and I've been reading through the FAQs and posts on the autobodystore.com forum. I think I'm ready to take the plunge and my car is almost completely disassembled. This is where I need help from the more knowledgeable folks on this forum to help me as I go through the process. Here's what I'm starting with.

This is a shot of the paint around the window, this is what the paint looks like on the passenger front quarter, all around the window and the mirror.

This is a shot of the passenger quarter.

The car is largely rust free. I think there may be some rust bubbles brewing near the Targa bar inside the door jam, but I'll grind those out and weld them. All of the panels except the trunk lid are very straight. The engine lid has some indentations where people have pushed down on it when closing it. As a result I think that the engine lid will need a little metal work and bondo but the rest of the car will not require much if any.

So here come the questions;

1. Should I strip the car to bare metal or just sand away the clear and top coat? I don't want to strip away the galvanized coating on the metal so I'm wary of taking all of the paint and primer off. I had considered acid dipping the removable panels (front quarters, doors, hood, engine lid, targa bar) and chemical stripping the rest on the spot but some advice from the pros is definitely needed.
2. If I do remove just the clear and top layer of paint should I do this by hand with a block sander or use a 3M paint stripping disk at low RPM?
3. If I do go to bare metal is acid dipping the removable panels and chemical stripping the rest a decent strategy? Stripping out the whole car to acid dip the entire car is further than I want to go. If possible I want to leave the interior and electronics in as I'm not changing the color and don't have to paint the engine compartment and trunk.
4. What brand of epoxy primer would you recommend for sealing the car after I strip the paint? I'd like to use glasurit 2K paint for the top coat so I'm guessing it would have to be a compatible paint.
5. Should I remove the hood, doors, trunk lid and quarters and refinish them of the car? I see some rust stains along the gap between the car body and quarters so I definitely want to take them off and see whether I have some repair to do. Should I just remove the quarters, deal with the rust, then reattach them and finish them on the car?

OK, enough questions for now I think. I'll have plenty more as I go along. I'd like to start stripping the paint next weekend so your advice will be appreciate. Here are a few pics of the cars current state.

962porsche · 03:55 AM

there is no need from what i'm looking at for a total strip . its the clear that failed . so i would just strip off the top coats . it looks to me like the L. & R. QTR's are repaints . as for dipping not on this kind of a job . you can block strip starting with an 80 or 100 grit paper then move down to a 180 or 220 before priming . being a X- glaurit tech rep and a shop owner that uses glasurit . i would only use glasurit it is the oe finish ! in my shop we would remove all bolt on parts . fenders are in the front and QTR's are in the rear . so removing the QTR's would call for drilling out spot welds . one thing about targas rear glass . most glass shops don't do them . so if you plan on removing it make damb sure that you have some one to do the install . we do 2 or 3 rear targa glass installs a year and every car owner tells me the same thing . how can a glass co. say they don't do targas rear glass . things that make it a pain in the ass are having a 3rd brake light , rear defoger , new glass seal and moldings .

vulcan300 · 06-13-2010, 07:23 AM

Thank you very much for your advice. Not having to strip the car down to metal is a good thing. I've bought a large hand block sander so I guess I'll load up on some 100 grit paper and get sanding. How do I know when I've sanded enough?

Once I've sanded the the top coats off do I put on a coat of epoxy primer before using filler? What type of epoxy primer would you recommend? There is one area in the center of the hood that will need a little attention, the engine lid, and the hole in the side that I found underneath the rocker. I'll definitely need to use some filler there. What type of filler would you recommend for these spots? After the filler is on and sanded what would you recommend for use as a sealer before the top coat?

As for the glass I'm removing all of it. I pulled the front glass out last weekend and packed it away for safe keeping. I've cut the seal for the back glass and I'll pull that out this coming weekend when I start to sand. My mechanic has done replacements of this glass in the past and I've also read up on it so I think I have a fighting chance of getting the back glass in without having to call in outside help.

vulcan300 · 06-15-2010, 04:09 AM

Bump.

I'm going to start saning this coming weekend so any advice about how to know when to stop would be appreciated.

962porsche · 06-15-2010, 01:40 PM

when the clear and most of the color coat is gone. as you block sand you will see the layers of materials clear , base color , sealer , then primer . kind of like rings on a tree . the clear will take a little work to sand . as for the base you will sand right thru that . an air sander or electric palm sander will work good just to sand off most of the clear . but don't over sand with the electric sander . remember long sanding strokes and in a cross pattern . and on the tops of the fenders were they are rounded don't sand the length of the panel . it will put chop lines in it .

vulcan300 · 06-16-2010, 04:05 AM

So for the flat panels I'll use long criss cross strokes without too much pressure. For the curved sections like the front fenders I'll use a sanding motion perpendicular to the long axis of the panel. Does that sound right? are their any special tips for sanding areas like the crease on either side of the hood?

Would you recommend using paint stripping discs on a rotary air tool for this or is it better to use regular sandpaper?

vulcan300 · 06-18-2010, 04:01 AM

What epoxy primer is recommended for use as a coat over the sanded base? What type of sandable primer/sealer should I use once I have done bodywork and bondo over top of the epoxy primer? I'm going to use a Glasurit 2K top coat so what type of paints should I get to ensure compatibility?

How much of each type of paint should be sufficient? 1 Gallon or more?

962porsche · 06-18-2010, 02:13 PM

you only need an epoxy primer if your down to bare metal . you will have some spots but i can't tell you untill you strip the clear . i would not use bondo body filler . i would use an other brand like evercoat or USC brand pro7 thats good to use over bare metals , paints and primers .

vulcan300 · 06-18-2010, 03:32 PM

OK, I'll post up pictures of what I have after I strip the clear and top coat. Thanks for the continued advice!

Smoker324 · 06-22-2010, 07:18 PM

Sorry to thread jack -- but what if your sanding does not go to bare metal -- just down to the factory primer. Do you need to apply any sealer before doing a bc/cc iso based urethane ?

962porsche · 06-23-2010, 03:55 AM

after the real good blocking is done in most cases you will have some spots broken thru to bare metal . so it that point you would spot E-prime them . you can go wet on wet over the E-primer with 2 to 4 coats of a high build primer . guide coat the high build prime then give it an other good wet sanding also block sanding that . i would not try to just seal and top coat . sealers don't have the mill build needed to achieve any proper hold down of rings or srinking in . sealer is a product used to achieve better adhision and to give a uniform color before your top coats are applyed . sealers will have a hard time to fill any sanding grit cut over a 320 paper .