Sheetmetal work - compound curve

[player1up]

I've decided to tackle the rust around the rear window on my Duster. It's a pretty common problem and I've found that the rear seal was pulling away from the lower corners causing water wick between the seams and rust out the ledge almost all the way down to the tail lights ( under the seam sealer ).

I've started cutting away at the corner and a little up onto the top edge of the quarter panel, BUT right at the corner is a compound curve...top quarter panel is concave, where it wraps down into the window opening is concave, AND where it transitions to flat is also concave. It's like an S shaped banana

What is the best way to make a piece that goes there?
1. Bend and hammer it out of a single piece?
2. Bend each concave piece and weld the pieces together?
3. Bend one piece and cut relief notches to get the additional curvature then re-weld the cuts?
4. Something I haven't thought of?

I've done this before and used option 3 but it's very time consuming to get it to look right after all of the cuts have been closed up, just trying to get some advice from any Guru's out there.
Keep in mind that these are smallish pieces so I'm doing it all by hand...and it's taken me 4-5 hours just to come up with rough piece to test fit

 

[Woods74]

Good body work takes, time, lots of it. A little mini black hole should form and your day will start and end in the same sentence when your doing it right.

I'd go with #3; Perfect is the enemy of the good on these cars, getting fancy with the welds is a waste of time IMO, think about the level of finish of metal on the rest of the car and ask yourself, am I going too far? Some pictures would help.

 

[younggun2.0]

I think you would be better off finding someone that is willing to cut the piece out of a donor car.

 

[CudaChris67]

I've decided to tackle the rust around the rear window on my Duster. It's a pretty common problem and I've found that the rear seal was pulling away from the lower corners causing water wick between the seams and rust out the ledge almost all the way down to the tail lights ( under the seam sealer ).

I've started cutting away at the corner and a little up onto the top edge of the quarter panel, BUT right at the corner is a compound curve...top quarter panel is concave, where it wraps down into the window opening is concave, AND where it transitions to flat is also concave. It's like an S shaped banana

What is the best way to make a piece that goes there?
1. Bend and hammer it out of a single piece?
2. Bend each concave piece and weld the pieces together?
3. Bend one piece and cut relief notches to get the additional curvature then re-weld the cuts?
4. Something I haven't thought of?

I've done this before and used option 3 but it's very time consuming to get it to look right after all of the cuts have been closed up, just trying to get some advice from any Guru's out there.
Keep in mind that these are smallish pieces so I'm doing it all by hand...and it's taken me 4-5 hours just to come up with rough piece to test fit

I think it depends on where your skills are. If hammering out 3 pieces and welding them sounds easier that making precise cuts, do it! If you think you are better and grinding and dealing with the warpage from the heat of additional welding and grinding of filling in all the mini cuts, do that.

I have not done this specific application, but i do work somewhere between #1 and #2

Doner piece is not a bad idea, there is always someone cutting up these cars (though they may have the same issue)

 

[jos51700]

I think MObodyman is your ally here.

 

[clhyer]

I agree with PoisonDart, #3 is what I have done in the past.
C

 

[player1up]

Thanks guys. I'm actually getting a piece from a donor for the passenger a-pillar, but thought this would be fairly easy...boy was I wrong. I thought about option 2 as I'm not scared of welding and grinding, but thought that warpage would be an issue trying to weld pieces with only one curve, especially after it has been bent/hammered on.
PoisonDart74 does have a point about the finish on these old cars. I've found all kinds of welding slag, pieces "kinda" welded together, welding wire hanging out under the package tray and other general craptastrophies
Most of this area will be under the trunk lid when closed or covered by the trim so I guess I really only care about where the glass seal sits and the top edge ( which i'm doing fine with.

 

[440abody]

AMD makes the piece I think you are referring to.





650-1370more info

70-76 Duster Deck Filler PanelAlso fits 71-2 Demon and 73 -up Dart Sport

$129.95

 

[player1up]

440abody.....Where were you 2 weeks ago??? crap...I've been doing it the hard way!!!
Actually the piece I was having an issue with was the...see green oval in pic.
View attachment 20130510_182441 (Small)_highlight.JPG

This is where I'm at today....
View attachment 20130516_212600 (Small)_highlight.JPG

Now, I know I'm not the best welder in the world, but I'm pretty happy with it so far even though I've still got lots of work ahead of me...

OH, what I ended up doing was making the curve in the horizontal pieces ( fairly easy as all I had to do was make a curved mark, bend one side up, then bend the other side down about .3 inches away ) then slotting the horizontals to bend the vertical piece...then welded up all of the slots, kind of a pain, but turned out ok.

I do see the trunk gutters on AMD's site, but I'd still need the top roll over edge of the quarter panel...and I'm not buying an OEM style replacement just to hack it up...but hey, at least there's more of this stuff available now...

Oh, and thanks a lot...I ordered the trunk gutters...you know what they say, over budget and behind schedule
Apparently MOPAR stands for Mostly Overpriced Parts And Rarities

 

[FISHBREATH]

What I did in the past for such complicated pieces was to make a template out of thin cardboard, such as was used by clothes cleaners for wrapping ironed shirts around. I used it to mark steel for cutting. Just rough cut the cardboard to fit beneath the hole and trace the hole with a pencil. Once you cut out the steel, you can hand-bend it to get it in the ballpark before welding it in.