cudak888: 1971 M-code "Soylent Green" - 2024: Help me measure the frame!

[marks73]

I know NPD has the rear bracket that makes up the rear frame, but you may want to verify they have the front bracket.

http://www.npdlink.com/store/products/1971_mustang_plate_gas_tank_strap_front_mounting_repro-146899-484.html?shop_by_year=1971

-Kurt

That's cool! Didn't have it last spring when I did mine.

 

[cudak888]

http://www.npdlink.com/store/products/1971_mustang_plate_gas_tank_strap_front_mounting_repro-146899-484.html?shop_by_year=1971

-Kurt

That's cool! Didn't have it last spring when I did mine.

I hope they also carry reproduction body parts for me too - had to take today off from making any progress, thanks to bruising my arms and straining my back from having crawled in and out of that trunk for the last 3 days straight.

If I keep this up, I'll need Lee Major's bionic doo-dads from the Six Million Dollar Man pretty soon. Heck, at least it'll be reasonably period correct with the car.

-Kurt

 

[marks73]

http://www.npdlink.com/store/products/1971_mustang_plate_gas_tank_strap_front_mounting_repro-146899-484.html?shop_by_year=1971

-Kurt

That's cool! Didn't have it last spring when I did mine.

I hope they also carry reproduction body parts for me too - had to take today off from making any progress, thanks to bruising my arms and straining my back from having crawled in and out of that trunk for the last 3 days straight.

If I keep this up, I'll need Lee Major's bionic doo-dads from the Six Million Dollar Man pretty soon. Heck, at least it'll be reasonably period correct with the car.

-Kurt

Wait until you get ready to weld that sucker back in under the car. Depending on you welding skills (and mine are marginal at best when working upside down) I chose to cut mine at the bend that welds to the frame and weld the shock mount and tank support peices to the new trunk floor on a pair of saw horses. We took a ton of measurements to insure it would line back up with the tab I left on the frame and it turned out very well. The aftermarket metal was a PITA to get the mig set right for good penetration without blowing through the thinner metal of the trunk floor.

 

[cudak888]

Wait until you get ready to weld that sucker back in under the car. Depending on you welding skills (and mine are marginal at best when working upside down) I chose to cut mine at the bend that welds to the frame and weld the shock mount and tank support peices to the new trunk floor on a pair of saw horses. We took a ton of measurements to insure it would line back up with the tab I left on the frame and it turned out very well. The aftermarket metal was a PITA to get the mig set right for good penetration without blowing through the thinner metal of the trunk floor.

I'm making sure that the shock tower remains one with the frame, and I'm going to follow Q's advice to drill the replacement trunk floor and weld it from the top. Near as I can figure it, the only thing I'll be doing that does not involve welding directly downwards are the welds at the inner wheelwell. Not sure how I intend to tackle the existing left dropoff though.

Likewise, I intend to weld the gas tank hanger to the shock mount before putting in the trunk floor. If it sags when I'm trying to weld it, I'll put some weight on the trunk floor and jack the hanger temporarily.

What settings did you use, and what MIG are you running? I bought a Hobart 140 for the job, 0.023 wire w/shielding gas, voltage set to its lowest setting ("1") and wire speed @ 30. What trunk floor did you use? The original appeared to be thicker than the frame rails.

-Kurt

 

[cudak888]

More progress today - just pulled out the LH corner.

-Kurt

 

[pegasus]

Great progress so far, Good on you for getting in and giving it a go, slow and steady, and you'll soon run out of spot welds to drill, Even if it seems at times your not getting anywhere and it's taking forever.

 

[cudak888]

Great peogress so far, Good on you for getting in and giving it a go, slow and steady, and you'll soon run out of spot welds to drill, Even if it seems at times your not getting anywhere and it's taking forever.

I'm already running out of spot welds. Soon as the corrisponding left-hand corner comes out (and the framerails are tacked together), I'm cutting the whole back end out in one piece - in short, the remaining floor pan, taillight panel, and subframe connector. Right-hand trunk dropoff comes out in pieces too, as it's not salvageable.

Since the subframe connector is damaged, and there are so many bad brazings between it and the taillight panel (god only knows who did the job and how long ago), there is no reason to take it apart neatly, seeing as it is all destined for replacement.

-Kurt

 

[marks73]

Wait until you get ready to weld that sucker back in under the car. Depending on you welding skills (and mine are marginal at best when working upside down) I chose to cut mine at the bend that welds to the frame and weld the shock mount and tank support peices to the new trunk floor on a pair of saw horses. We took a ton of measurements to insure it would line back up with the tab I left on the frame and it turned out very well. The aftermarket metal was a PITA to get the mig set right for good penetration without blowing through the thinner metal of the trunk floor.

I'm making sure that the shock tower remains one with the frame, and I'm going to follow Q's advice to drill the replacement trunk floor and weld it from the top. Near as I can figure it, the only thing I'll be doing that does not involve welding directly downwards are the welds at the inner wheelwell. Not sure how I intend to tackle the existing left dropoff though.

Likewise, I intend to weld the gas tank hanger to the shock mount before putting in the trunk floor. If it sags when I'm trying to weld it, I'll put some weight on the trunk floor and jack the hanger temporarily.

What settings did you use, and what MIG are you running? I bought a Hobart 140 for the job, 0.023 wire w/shielding gas, voltage set to its lowest setting ("1") and wire speed @ 30. What trunk floor did you use? The original appeared to be thicker than the frame rails.

-Kurt

I have a Lincoln SP125-Plus. I was using .030 wire with argon and CO2 gas. Changed over to .023 Fluxcore with the gas and it all came together

 

[cudak888]

I have a Lincoln SP125-Plus. I was using .030 wire with argon and CO2 gas. Changed over to .023 Fluxcore with the gas and it all came together

Fluxcore wire with the gas? Never heard of that one. What polarity are you running the welder at with that wire?

Tell me, did you remove your weld-through primer in the areas you were welding, or did you burn through them?

-Kurt

 

[marks73]

I have a Lincoln SP125-Plus. I was using .030 wire with argon and CO2 gas. Changed over to .023 Fluxcore with the gas and it all came together

Fluxcore wire with the gas? Never heard of that one. What polarity are you running the welder at with that wire?

Tell me, did you remove your weld-through primer in the areas you were welding, or did you burn through them?

-Kurt

My neighbor Bill the retired welder recommended using the fluxcore with the gas on the same polarity as the solid wire. I used the weld through primer though I must admit it seemed to make getting the metal hot enough difficult at the lower settings. The trunk floor came from NPD and I had very little issue with it lining up or metal thickness.

The problem of blow through was getting the gas tank front hanger and shock mount hot enough for penetration without just blowing a hole in the floor pan. I started at the edge of the floor pan because that is where the weld is the coldest, then moved to the brackets and back and forthed on them a little before circling into the center. I ended up at 3 and D on that portion. Then went back to a lower setting to fill the holes I made.

 

[cudak888]

No pictures today. Removed the undercoating on the left side inner fender (somehow 10 times more miserable than the LH side), and pulled the fuel line. No spot welds drilled.

My neighbor Bill the retired welder recommended using the fluxcore with the gas on the same polarity as the solid wire. I used the weld through primer though I must admit it seemed to make getting the metal hot enough difficult at the lower settings. The trunk floor came from NPD and I had very little issue with it lining up or metal thickness.

The problem of blow through was getting the gas tank front hanger and shock mount hot enough for penetration without just blowing a hole in the floor pan. I started at the edge of the floor pan because that is where the weld is the coldest, then moved to the brackets and back and forthed on them a little before circling into the center. I ended up at 3 and D on that portion. Then went back to a lower setting to fill the holes I made.

Is that to say you were welding the trunk floor to the hanger AND the shock mount all at once? Remind me if this was from the bottom or the top.

My plan is to mount the hanger to the shock mount (drilling holes in the hanger to fill, Q-style), then the trunk floor on top of that, with alternating holes to clear the pre-existing welds. Wouldn't that be easier to execute?

-Kurt

 

[marks73]

I did mine out of the car

 

[Qcode351mach]

Kurt,

You fit the rear cross member first...Use a few sheet metal screws...Then the floor..also a few screws..Then the rear body panel...INSTALL the gas tank including the filler neck..This will locate the position of the gas tank strap bracket..All of your holes for plugs should be around a 3/16"-1/4" DO not use flux core wire with gas..NOT an acceptable repair method..Ask any body shop about that..Do yourself a favor & get some ESAB All-State Easy Grind 023 wire..BIG difference in the way it welds & grinds..YOU can thank me later

http://www.weldingsupply.com You should always do some test welds on some scrap metal the same thickness as your going to weld to dial in the welder..Theres plently of videos on you tube on how to dial in the welder..

 

[cudak888]

LH side is out. Time to bracket the rails together and get the whole kit and kaboodle out of the back end:

I did mine out of the car

Going to pull this one off while it's in there. Fuel line is out, so I shouldn't have any problems - safetywise.

Kurt,

You fit the rear cross member first....

Adds up with everything I've read. Hopefully, I'll be spared any surprises when it comes down to the job.

-Kurt

 

[marks73]

NOT an acceptable repair method..

I've not found this! What documentation is this based off of?

 

[Qcode351mach]

NOT an acceptable repair method..

I've not found this! What documentation is this based off of?

I-Car..the standard of the collision industry..

http://www.i-car.com/html_pages/training_programs/welding/structural.shtml

I have this certification..

 

[Mikes73]

Ruh roh!, I used flux core on mine, hopefully my trunk floor doesn't fall out lol. I can pick the whole back end of the car up off of the ground by the trunk floor so I'm thinking it will be okay. It is alot stouter than it came from the factory. Cudak888, the car looks like it is coming alot great.

 

[Paul of MO]

They are talking about using flux core with gas - I tried it and it did not weld very smoothly. Used it because I had not used it all up and had already swapped the polarity inside the welder.

Get the easygrind stuff as per Scott - it welds like butter.

I think part of the secret to pretty welds is the equipment and the consumables. With good wire I weld "almost good-ly"

- Paul

Ruh roh!, I used flux core on mine, hopefully my trunk floor doesn't fall out lol. can pick the whole back end of the car up off of the ground by the trunk floor so I'm thinking it will be okay. It is alot stouter than it came from the factory. Cudak888, the car looks like it is coming alot great.

 

[cudak888]

Almost forgot - while crawling under the car today, I found out that the PO had mounted a pair of Flowmaster mufflers on it.

A few dollars saved right there.

-Kurt

 

[marks73]

NOT an acceptable repair method..

I've not found this! What documentation is this based off of?

I-Car..the standard of the collision industry..

http://www.i-car.com/html_pages/training_programs/welding/structural.shtml

I have this certification..

Sorry, still can't find it.