Empty shell to finished car
01-27-2012, 05:32 AM
#91
Three Wheelin'
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Maybe I am too late, but sanding the body is a very tricky and touchy deal. The entire body is hot dipped galvanized. The layer is very thin and can be sanded though. It is best to us chemical strippers on the body. A tip to the air craft stipper. It works best on warm dry days. Done on the right day at the right temperature and the paint will just bubble off. I use scrappers like a wall paper scarper with a changable blade and some brass brushes to get in the tight places.
After the paint is stripped be sure to wash the body down throughly with warm water - mabye with some baking soda mixed in to neutralize and remove the stripped. Failure to get the stripper reidue off will cause the primer to spring off the surface. There are some prep agents than can further cure the zinc making it ready for paint. After doing any body work and filling dings I shoot on a coat of DTM from the restroration shop. This provides a good sold base and is easy to sand.
If there are places that have been sanded through you can get a can or two of zinc primer. it goes on thin and replaces the zinc coating. Of course it is not as good and easily sands through but I have a rusted panel I cured with some rust inhibitor and then sprayed with the zinc primer and it has sat out for a while now with no issues and no reoccuring rust.
You are right bare metal is a good place to start, but be careful. Porsche did some major prep on some of the panels before paint. There will be a good deal of blocking before you have a real paintable surface.
Nice job
After the paint is stripped be sure to wash the body down throughly with warm water - mabye with some baking soda mixed in to neutralize and remove the stripped. Failure to get the stripper reidue off will cause the primer to spring off the surface. There are some prep agents than can further cure the zinc making it ready for paint. After doing any body work and filling dings I shoot on a coat of DTM from the restroration shop. This provides a good sold base and is easy to sand.
If there are places that have been sanded through you can get a can or two of zinc primer. it goes on thin and replaces the zinc coating. Of course it is not as good and easily sands through but I have a rusted panel I cured with some rust inhibitor and then sprayed with the zinc primer and it has sat out for a while now with no issues and no reoccuring rust.
You are right bare metal is a good place to start, but be careful. Porsche did some major prep on some of the panels before paint. There will be a good deal of blocking before you have a real paintable surface.
Nice job
01-27-2012, 10:50 AM
#92
Rennlist Member
Thread Starter
Hi Dan,
I appreciate your insights and expertise and helpful suggestions, they are always welcome and appreciated. I contemplated using chemical stripper, but decided against it for a few reasons, mostly because possible adhesion problems that occur if it is not completely neutralized before priming. The 928 body has a lot of nooks and crannies that are very difficult to get to, and I did not want to risk any issues down the road with paint lifting. Also, the paint manufacturer warns against chemical and etching products, and recommends a bare metal surface with a 80 grit texture for maximum adhesion and longevity of the epoxy primer.
I spent a great deal of phone time with HoK technicians, and one point that I think is useful for others planning to paint their car is the issue of flex agent. The modern paint system that HoK uses does not need it and should not be mixed with flex agent as the properties of the urethane paint and epoxy primers are extremely flexible. It is designed as such and they do not even make a flex agent because it is not required. This is of course not necessarily true for other paints on the market, just for my specific situation. They do however, recommend to not use the epoxy primer on the urethane bumpers and plastic pieces, and instead use their KD3000 products on those, which is a hybrid epoxy surfacer/sealer.
To give a breakdown of what products are being applied:
Bare steel and aluminum: KP2CF Epoxy primer
Plastic and urethane parts: KD3000 (surfacer/sealer, comes mixed in many colors)
Sealer on top of epoxy primer: KD3001 (black version of the sealer, also used as a guide coat)
Base coat: S2-25 Jet black (their newest and deepest black with pigments from Germany)
Pearl effect package (color not decided yet)
Clear Coat: USC01 Show Klear (yes they spell it that way)
Everything is being applied with HVLP guns, through double moisture/oil separators, and then through additional desiccant/coalescing filters. Of course, as you say it will take a lot of block sanding before the car will see any color coat
Cheers!
Carl
I appreciate your insights and expertise and helpful suggestions, they are always welcome and appreciated. I contemplated using chemical stripper, but decided against it for a few reasons, mostly because possible adhesion problems that occur if it is not completely neutralized before priming. The 928 body has a lot of nooks and crannies that are very difficult to get to, and I did not want to risk any issues down the road with paint lifting. Also, the paint manufacturer warns against chemical and etching products, and recommends a bare metal surface with a 80 grit texture for maximum adhesion and longevity of the epoxy primer.
I spent a great deal of phone time with HoK technicians, and one point that I think is useful for others planning to paint their car is the issue of flex agent. The modern paint system that HoK uses does not need it and should not be mixed with flex agent as the properties of the urethane paint and epoxy primers are extremely flexible. It is designed as such and they do not even make a flex agent because it is not required. This is of course not necessarily true for other paints on the market, just for my specific situation. They do however, recommend to not use the epoxy primer on the urethane bumpers and plastic pieces, and instead use their KD3000 products on those, which is a hybrid epoxy surfacer/sealer.
To give a breakdown of what products are being applied:
Bare steel and aluminum: KP2CF Epoxy primer
Plastic and urethane parts: KD3000 (surfacer/sealer, comes mixed in many colors)
Sealer on top of epoxy primer: KD3001 (black version of the sealer, also used as a guide coat)
Base coat: S2-25 Jet black (their newest and deepest black with pigments from Germany)
Pearl effect package (color not decided yet)
Clear Coat: USC01 Show Klear (yes they spell it that way)
Everything is being applied with HVLP guns, through double moisture/oil separators, and then through additional desiccant/coalescing filters. Of course, as you say it will take a lot of block sanding before the car will see any color coat
Cheers!
Carl
02-06-2012, 04:44 PM
#93
Rennlist Member
Thread Starter
Porsche tools...
OK, so I think I just bought one of the most expensive Porsche tools by weight...weighing only a few grams, this special tool is needed to remove the airbag crash sensors that are located on driver and passenger sides under the dash. But at least it is very shiny...and looks well made. If anyone else needs to remove these crash sensors, I can make it available as a loaner tool.
Also had some good weather and finished stripping the paint from the remainder of the outside body panels, and put 2 primer coats on. Will let it sit and see how the metal filler holds up and to verify any possible filler shrinkage on the spot welds on the front brace panel.
One thing I did notice during sanding down the panels and crevices was the fairly large differences in paint thickness...some areas, such as the rear 1/4 window frames had many more mils of paint in the corners than on the flat surfaces. The same for the area below the windshield, yet the A-pillars that the windshield rests on, only had a very very thin layer of paint with with a similarly thin layer of primer.
Cheers!
Carl
Also had some good weather and finished stripping the paint from the remainder of the outside body panels, and put 2 primer coats on. Will let it sit and see how the metal filler holds up and to verify any possible filler shrinkage on the spot welds on the front brace panel.
One thing I did notice during sanding down the panels and crevices was the fairly large differences in paint thickness...some areas, such as the rear 1/4 window frames had many more mils of paint in the corners than on the flat surfaces. The same for the area below the windshield, yet the A-pillars that the windshield rests on, only had a very very thin layer of paint with with a similarly thin layer of primer.
Cheers!
Carl
02-21-2012, 08:28 PM
#97
Rennlist Member
Thread Starter
Unfortunately the temperatures have been below ideal for putting down primer, so I decided to unpack the non-sunroof panel and start marking the final areas on the roof structure to cut out. Had my first real setback in this project, as the roof panel had some damage that obviously happened during shipment to the driver's front edge. Unfortunately it is way past the 30 day claim period with UPS, so it looks like I have to get the body shop to straighten it out.
Also measured the clearance at the rear b-pillar cross member, to see if it would clear the non-sunroof headliner. Turns out I had not cut enough, and the headliner rubs against the metal here, so it looks I need to cut another 0.5 inches which will give enough clearance, including any padding i might add for sound reduction. In the picture you can see approximately 0.68 inches from the panel overlap, of which 0.5 inches will be removed.
Finally selected a paint/body shop for this project, and currently have a slot for July. The do about 80% custom jobs, and very little insurance claims, which should avoid any hassles with my car being put on the back burner (famous last words..).
Had a very long and pleasant tour with the owner of the shop, and he came across as very helpful and willing to go along with my specific requirements.
I also decided to go with GTS rear fenders, which should be on their way from 928's-r-us right now. Will post some pictures when they are unpacked and checked for damage
Also measured the clearance at the rear b-pillar cross member, to see if it would clear the non-sunroof headliner. Turns out I had not cut enough, and the headliner rubs against the metal here, so it looks I need to cut another 0.5 inches which will give enough clearance, including any padding i might add for sound reduction. In the picture you can see approximately 0.68 inches from the panel overlap, of which 0.5 inches will be removed.
Finally selected a paint/body shop for this project, and currently have a slot for July. The do about 80% custom jobs, and very little insurance claims, which should avoid any hassles with my car being put on the back burner (famous last words..).
Had a very long and pleasant tour with the owner of the shop, and he came across as very helpful and willing to go along with my specific requirements.
I also decided to go with GTS rear fenders, which should be on their way from 928's-r-us right now. Will post some pictures when they are unpacked and checked for damage
Last edited by FLYVMO; 02-21-2012 at 08:43 PM.
02-22-2012, 05:05 AM
#99
Three Wheelin'
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That small dent on the roof should not be much of a problem. If I rememebr right from the time years back that I put a roof on, there are some extra pieces added to the car for the sun roof. Take a look at the pet and I think you will find a number of supporting pieces for the sun roof that should be removed.
Other than that we pretty much just spot welded the new roof in place.
Other than that we pretty much just spot welded the new roof in place.
02-22-2012, 08:19 AM
#100
Rennlist Member
Thread Starter
Dan, thanks for the encouraging words. Hopefully the body shop can straighten it out. As far as the interior sunroof structure goes, it is completely removed. I only have the spot welds left to drill out, but since this was my first sunroof removal, I did not know how much of the rear brace I needed to cut. So to be cautious I did the "surgery" in steps, and removed the outer skin first, to be able to see "inside" the sunroof cassette. The picture shows one of the two side welds that needs to be cut, which if I remember is the only place the other than the rear b-pillar brace where the sun roof cassette is attached.
When you did your sunroof, did you use any panel adhesive in addition to the spot welds?
Cheers!
Carl
When you did your sunroof, did you use any panel adhesive in addition to the spot welds?
Cheers!
Carl
02-22-2012, 06:04 PM
#101
If i could ask what step gts quarters worth these days given all the price rises? Tia
Unfortunately the temperatures have been below ideal for putting down primer, so I decided to unpack the non-sunroof panel and start marking the final areas on the roof structure to cut out. Had my first real setback in this project, as the roof panel had some damage that obviously happened during shipment to the driver's front edge. Unfortunately it is way past the 30 day claim period with UPS, so it looks like I have to get the body shop to straighten it out.
Also measured the clearance at the rear b-pillar cross member, to see if it would clear the non-sunroof headliner. Turns out I had not cut enough, and the headliner rubs against the metal here, so it looks I need to cut another 0.5 inches which will give enough clearance, including any padding i might add for sound reduction. In the picture you can see approximately 0.68 inches from the panel overlap, of which 0.5 inches will be removed.
Finally selected a paint/body shop for this project, and currently have a slot for July. The do about 80% custom jobs, and very little insurance claims, which should avoid any hassles with my car being put on the back burner (famous last words..).
Had a very long and pleasant tour with the owner of the shop, and he came across as very helpful and willing to go along with my specific requirements.
I also decided to go with GTS rear fenders, which should be on their way from 928's-r-us right now. Will post some pictures when they are unpacked and checked for damage
Also measured the clearance at the rear b-pillar cross member, to see if it would clear the non-sunroof headliner. Turns out I had not cut enough, and the headliner rubs against the metal here, so it looks I need to cut another 0.5 inches which will give enough clearance, including any padding i might add for sound reduction. In the picture you can see approximately 0.68 inches from the panel overlap, of which 0.5 inches will be removed.
Finally selected a paint/body shop for this project, and currently have a slot for July. The do about 80% custom jobs, and very little insurance claims, which should avoid any hassles with my car being put on the back burner (famous last words..).
Had a very long and pleasant tour with the owner of the shop, and he came across as very helpful and willing to go along with my specific requirements.
I also decided to go with GTS rear fenders, which should be on their way from 928's-r-us right now. Will post some pictures when they are unpacked and checked for damage
02-22-2012, 06:36 PM
#102
Carl, Unbelievable job!!! What....*****! I would love to do what you're doing. I'm sure my wife might take a different stance but... I am doing a sunroof delete, what ever pic you could show would be great. It's the first time I've ever cut my car. I'm scared. I've got the panel and the three cross members and a body guy who'll work with me. Please any info would set my mind at ease. Thanks, Brian
02-22-2012, 07:46 PM
#103
Rennlist Member
Thread Starter
Slate blue: I don't mind you asking
Seriously, they're expensive, and priced differently side to side, but the total ends up being mid 5K. You would think they are made of Unobtainium, but no such luck.
Leadass: Luckily I have a very patient wife, so I can't complain. I'll be happy to share my pictures with you. Most are already posted here but if you want some more, PM me with your email, and I'll send them as I take more pictures.
Cheers!
Carl
Seriously, they're expensive, and priced differently side to side, but the total ends up being mid 5K. You would think they are made of Unobtainium, but no such luck.
Leadass: Luckily I have a very patient wife, so I can't complain. I'll be happy to share my pictures with you. Most are already posted here but if you want some more, PM me with your email, and I'll send them as I take more pictures.
Cheers!
Carl
02-22-2012, 09:04 PM
#105
Rennlist Member
Thread Starter
Hi Tony!
How's that steering wheel coming along? Yes, she is great, can't complain. As long as she gets more attention than the car, all is good
Cheers!
Carl
How's that steering wheel coming along? Yes, she is great, can't complain. As long as she gets more attention than the car, all is good
Cheers!
Carl