new drip rails

[chargd72]

Ok, getting ready to attack these drip rails soon.  I have some doner rails off a 73 satellite that are cut up about 6 inches into the roof.  My question for you metal guys, would you cut and weld on the red line or green line?  I thought it would be easier to hide work on the red line.  Plus I wouldn't have to worry about warping the roof as much.  What do you experienced guys think?

[JB400]

I'd choose the green line, make sure your getting into good metal.  Choosing the red one, you might get into some rusty metal that you can't see and end up going to the green line anyway.

[Dino]

I'd say somewhere inbetween.  Wherever you find solid, healthy, non pitted metal is where you want to weld.  The entire section is curved which will make this a very easy job as long as you measure twice and take your time welding it.  Another factor to consider is what will be underneath your weld?  You will have to at least primer and protect the welds so take a look underneath and see what you have.  When you think you have the right line, dril some very fine holes on it and look at the inside to make sure you're clear.  When you're good to go use a thin blade to cut through the roof and lay the piece you removed on the new part to get an exact measurement.  You'll have to cut away some of the old to make it lay on the new.

You can also make a small jig in case something goes wrong.  Take some scrap wood and make something that shows you exactly where the outer and lower edge of the drip rail is so you can double check your work when the new piece is tacked in place.  The last thing you want to find out when it comes back from paint is that the windows no longer seal.   

[Patronus]

I'd vote green. You'll have to skim out at least that far anyway. Those inter grip clamps from Eastwood might help..

[chargd72]

Thanks guys.  Around the green line is where it will be.  I've seen those clamps on eastwood.  Those sure would be useful for this task.

[Patronus]

Also, depending where you cut the new one to piece in, you could just trace it and then cut. Lots of the time if you save your patch and trace it on new metal you can save hours of measure/cut/fit.. Just some helpful hints for ya.. 

[chargd72]

Thanks for the tip!

Also, those intergrip clamps from Eastwood are on sale right now if anyone is interested.  Sale price $9.99 for four vs regular price of $16.99.  Got me some.

[71_Charger_R/T]

Just FYI you will pretty much have to cut to at least the green line. As the drip rail is not part of the roof skin. It is the topmost layer of the roof inner structure. I would be inclined to drill out all the spot welds on the roof skin, remove it, then replace the drip rail pieces and reinstall the skin with a minimal amount (only as much as needed) of the skin replaced. You'll be able to see how far back the rust goes on the skin when it's removed, otherwise it will be hidden between the skin and inner structure, and only exploratory cutting will reveal it. I did this same repair on my car but used a donor skin as well. Any 71-74 B-body 2 door roof skin will work. The drip rails on the other hand, are different lengths depending on year and model, 1971 and 72 non-SE Charger are the longest.

[Mike DC]

 
Any job like that, I do it in a bunch of stages.  


Make a first-draft cut on the car very close to the rusted area, closer than you think you need to.  (You'd be surprised how often your first assumed safe line actually ends up too far.)  Then cut down the patch panel somewhat (assuming it starts out bigger than you want as well).  Then make a further cut on the car.  Then another one on the patch.  Etc.  

Gradually bring the hole in the car and the patch to the same size, comparing them to each other often.  You may find you want to change the shape of the splice along the way.  Doing it in stages makes it a hell of a lot easier.