Quarter Panel Again! Weld strength, options?
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Car: 1986 Firebird
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Quarter Panel Again! Weld strength, options?
Hi guys, it's me again, the quarter panel guy.
Nobody noticed my old question at the end of the last "big thread" about the quarter panel... so I'm going to ask it again. I think you guys got tired of all the big pictures loading up in that old message!
So; when they cut the back half of that Firebird off for me, I figured I'd just weld the half onto my car. It'll be much easier, and should be faster. Instead of screwing around with drilling out spot welds and welding upside down and in corners and etc, if I weld in the complete half, all I'll have to do is weld down the center of the car, on flat pieces, and it'll make TomP's life much easier. (Well, with the exception of dropping the gas tank, and somehow pushing the car into the garage- ugh.)
Now, when they cut the half off, it's not a true half. It's more like a 3/8 of a Firebird. The cut (which is damn clean, looks like a saw?? No distortion at all!!) extends about a 1/2 inch past the right rear frame rail. That's not enough to make a flange. I have two options, one is hell, but strong, and one "might be as strong".
Option #1 (hell): I would use a regular drill (not a spot weld drill) to drill out the spot welds holding MY right rear frame rail to MY car. Then, I would cut MY car down the "middle" of that rear frame rail. Then, I would flange MY car's floor "upward". Then I would place the new half-a-car under that flange. I'd line up the holes I drilled through MY car with the frame rail of the NEW half. That would give me "exact" placement as regards the rear frame rail, and I'd weld it up.
Option #2 (easier): I would cut my car exactly (tough) to meet the new half. The idea would be to make a butt-weld to join the two halfs- but I'm concerned about strength. So, my idea would be to reinforce that buttweld with a third piece of steel. It would be a combination of a butt weld (two pieces meeting) and a lap weld (one piece on top of another piece). I've attached a picture.
Which do you think would be stronger?? Option #1 or Option #2?? Or would they be equally strong? Thanks!!
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
So; when they cut the back half of that Firebird off for me, I figured I'd just weld the half onto my car. It'll be much easier, and should be faster. Instead of screwing around with drilling out spot welds and welding upside down and in corners and etc, if I weld in the complete half, all I'll have to do is weld down the center of the car, on flat pieces, and it'll make TomP's life much easier. (Well, with the exception of dropping the gas tank, and somehow pushing the car into the garage- ugh.)
Now, when they cut the half off, it's not a true half. It's more like a 3/8 of a Firebird. The cut (which is damn clean, looks like a saw?? No distortion at all!!) extends about a 1/2 inch past the right rear frame rail. That's not enough to make a flange. I have two options, one is hell, but strong, and one "might be as strong".
Option #1 (hell): I would use a regular drill (not a spot weld drill) to drill out the spot welds holding MY right rear frame rail to MY car. Then, I would cut MY car down the "middle" of that rear frame rail. Then, I would flange MY car's floor "upward". Then I would place the new half-a-car under that flange. I'd line up the holes I drilled through MY car with the frame rail of the NEW half. That would give me "exact" placement as regards the rear frame rail, and I'd weld it up.
Option #2 (easier): I would cut my car exactly (tough) to meet the new half. The idea would be to make a butt-weld to join the two halfs- but I'm concerned about strength. So, my idea would be to reinforce that buttweld with a third piece of steel. It would be a combination of a butt weld (two pieces meeting) and a lap weld (one piece on top of another piece). I've attached a picture.
Which do you think would be stronger?? Option #1 or Option #2?? Or would they be equally strong? Thanks!!
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Here's a pic of what "Option 1 (hell)" looks like. See? It really is hell! Talk about a ton of work! And what if option #2 is the same strength for less work? I wonder how a body shop would do this. I bet they'd go with the Option #2 (above picture). ALL OPINIONS WELCOME!!!
Option 1, part A:
Option 1, part A:
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Car: 1986 Firebird
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Nobody has any ideas? C'mon, Body&Interior, someone's gotta have an opinion! Hell, think of it as cardboard & glue instead of sheetmetal & welding if ya have to! Think either method is stronger than the other? Or are they both the same?
#5
I honestly have no idea , lol , but if you have a digi camera, could you please document the whole process ? LOL ![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
I'm just about as nuts as you are and sometimes in the near future would like to try doing that too
heck sell it on cd's for $20 , I would buy it
lol
PS: you might be better off going to a good bodyshop and asking them a few questions.
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
I'm just about as nuts as you are and sometimes in the near future would like to try doing that too
heck sell it on cd's for $20 , I would buy it
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
PS: you might be better off going to a good bodyshop and asking them a few questions.
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I think as long as you have welds with good penetration, butt-welding will be sufficient. You can overweld on metal. If you were to go the direction of butting the pieces together "exact fit", I would at least spot in some alignment tabs to give you a '3rd hand' '& help keep things straight. Also, you'll have to watch out for the parts to 'draw' on you if you're going with a soild weld. Align the part where you want & tack it in place all over making sure it stays close to your original alignment. Come back & the start filling in with lots of tack welds or a few less small (¼-½") stitch welds. This will help keep the panel in place when you finish weld it. Using a flange would basically be the same as above except you'll need to apply more heat to assure the weld is getting penetration into the underlying metal, not just across the gap. The drawback is, too much heat on such thin metal, you'll watch it magically disappear in front of you. Ultimately, you'll need to be the one to decide since you're doing all the work. I'd personally say screw it & just skip to part #6.. less tired=more frosty beverage time
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dont do a continuous weld after u tack things in place. just do bottem welds in stead of running beads. becuz if u weld up everything after u tack it, u will more then like warp something and get pissed off. trust me just botten weld (means alot of tack welds to join the piece entire) the pieces together and u wont have a problem enless u scrwed something up lining things up.
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Car: 1986 Firebird
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Smurf, yeah, I'm going to be taking pictures throughout- unless I get on "one hell of a roll"!
But with me being fully covered (long sleeves & pants) in 90 degree weather (so I don't get burned while welding) will probably leave me taking a ton of breaks (and probably step #6!) so I don't pass out. ![Big Grin](https://www.thirdgen.org/forums/images/smilies/biggrin.gif)
Deadbird, thanks again!! So you think even for such a critical spot as this, a butt weld would be fine? I asked this question because to me, butt welds seem perfect for taking a quarter panel, but seem scary for taking a whole half of a car. But like you said, with good penetration, the butt weld won't really be a weld anymore, it'll be part of both metals. What scares me is that I'll be bringing over the passenger side's lower control arm mount, and the panhard rod mount. But if I don't have to back anything up with extra steel, hell, that makes things even easier! That just places the brunt of the work on measurements.
I think I might make a "fake axle" from some scrap control arm pieces I have. Instead of me always bringing my axle underneath the car, I might weld a bar between two control arms, and use that as my "measurement axle". Funny too how I'll be getting rid of my bent panhard rod. The car was totalled in a rear-end accident before I got it; a body man fixed it for his son, and sold it to me a few years later. So the panhard rod and it's upper right body mount have been bent ever since I got the car- now I'll need straight pieces!![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
And yeah '82z28/deadbird, I wasn't going to lay down a full bead. But I was planning to use tack welds to get the piece positioned. I figured after those initial tack welds, I'd do a bunch more- but then use 1/2" long welds to finish up. Should I just do tack welds all around?
Oh & db thanks for the info about the flange inducing too much heat. Hm; and I just bought a panel flanger from Eastwood. Oh well; I'm sure it'll come in handy one day!
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
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Deadbird, thanks again!! So you think even for such a critical spot as this, a butt weld would be fine? I asked this question because to me, butt welds seem perfect for taking a quarter panel, but seem scary for taking a whole half of a car. But like you said, with good penetration, the butt weld won't really be a weld anymore, it'll be part of both metals. What scares me is that I'll be bringing over the passenger side's lower control arm mount, and the panhard rod mount. But if I don't have to back anything up with extra steel, hell, that makes things even easier! That just places the brunt of the work on measurements.
I think I might make a "fake axle" from some scrap control arm pieces I have. Instead of me always bringing my axle underneath the car, I might weld a bar between two control arms, and use that as my "measurement axle". Funny too how I'll be getting rid of my bent panhard rod. The car was totalled in a rear-end accident before I got it; a body man fixed it for his son, and sold it to me a few years later. So the panhard rod and it's upper right body mount have been bent ever since I got the car- now I'll need straight pieces!
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
And yeah '82z28/deadbird, I wasn't going to lay down a full bead. But I was planning to use tack welds to get the piece positioned. I figured after those initial tack welds, I'd do a bunch more- but then use 1/2" long welds to finish up. Should I just do tack welds all around?
Oh & db thanks for the info about the flange inducing too much heat. Hm; and I just bought a panel flanger from Eastwood. Oh well; I'm sure it'll come in handy one day!
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
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