[HardcoreZ28]

Hey guys....I haven't been on this site in quite a while but need to do a blend unfortunately and was hoping to get some good advice.

I'm finishing up a 70 Mach 1 Mustang for a customer and while putting my rear window stainless on I noticed a crack in my bodywork. Last person to do the car did a hack job on the rear quarter replacement and I did my best to pretty it back up. There must have been some shifting where the new quarter meets the roof and I got a 1 inch hairline crack at the seam. I v'd it out last night and put some fiberglass in it.

I'm used to spraying whole cars and don't have much experience blending in repairs. The paint is about 8 months old and I have some left from the same can still. It's the top of the line PPG stuff....color and clear. An experienced guy I know suggested blending the clear into what I felt was a large area. The whole top of the rear quarter and into the roof. For a 1 inch repair I thought that was a lot....but like I said I don't have much experience with it.

What technique would you guys suggest and how large of an area?

 

[MARTINSR]

If you post a photo showing where it is we could be of more help. Take the photo showing the whole area and then mark the photo where the repair is if it can't be seen very easy.

I have to tell you the fiberglass repair is as close to worthless as you can get. It is VERY likely it will be cracked before it is buffed.

On the blending, if there is a sharp body line it is likely you can back tape it there and stop it. But post a photo for more help. Or at least give a detailed explaination of exactly where primer spot is and we can look at a photo of the car found on the net or go from memory as to how it could be done on a Mustang of that year.

Brian

 

[HardcoreZ28]

Brian....here's a pic of the car. It's assembled now but this shows where the crack is..... The black line on the bottom is an easy spot to backtape but there's no hardline on top since it goes into the roof. The actual primer spot should be less than 1.5"x1.5" when my repair is done. And aside from possibly lead...what else would you suggest besides fiberglass filler to prevent it from cracking again? The panel is welded in that area but with the flex associated with the unibody I'm sure it's always going see some tweaking.

Paul

 

[MARTINSR]

Brian....here's a pic of the car. It's assembled now but this shows where the crack is..... The black line on the bottom is an easy spot to backtape but there's no hardline on top since it goes into the roof. The actual primer spot should be less than 1.5"x1.5" when my repair is done. And aside from possibly lead...what else would you suggest besides fiberglass filler to prevent it from cracking again? The panel is welded in that area but with the flex associated with the unibody I'm sure it's always going see some tweaking.

Paul

There is NO way it is going to crack filler there if the quarter is welded properly, NO WAY. If we were talking about a 600 hp drag car with slicks, I'll listen, but that car, NO WAY.

I think you are going to be going "up and over" on that one, shooting the roof and other quarter. You could break it at that line pretty easy staying on top of the quarters. Spot painting it and blending out the clear is going to be a gamble. Being that clear is fresh it makes it much easier and higher posibility for success though.

Brian

 

[alexflacco]

You layed down too nice of a paint job to blend out the clear on this one. The sail panel is just so wide, and since you haven't done many clear blends before I would say you should clear both quarters and the roof like Martinsr suggested.

 

[mike the painter]

a "blend "in the clear is called "Burning" the clear..it cant be done in this case and if it can it will be seen at certain angles you can "blend "the base coat ,no problem but the entire rear section of the car will have to be cleared...roof and 1/4's as far as the seam goes...martin nailed it...most likly the welds were ground down to far and thats the worst spot to put a seam to begin with...I'd clean out the whole seam and get every bit of bondo out but if its not stepped and just butted together you may be in for trouble,just pray that the other side dont crack too...heres the proper placement of the seam and flange ,to prevent warpage.I know how tough it is to start all over again but its the only way to trouble shoot the problem,and the cheapest way in the long run.I feel for ya budd we've all been there,some people just dont care about quality just getting paid and should be thrown in the trunk and brought to the crusher.....but still I've seen worse!!!!