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54 Posts
Discussion Starter #61
Things are rolling - Finishing Wheel Well and Floor Mods

Things really fell like they are starting to roll along nicely. It took me so long to figure out the alignment of the A and B pillars, the roof cross braces, the quarters, and so on; so it feels nice that starting to progress along faster.

Here's the result of the widening of the passenger side wheel well, just like the other side:
20190803_123059 by 7T02S, on Flickr

Now it was time to take the back of the car back apart and get the floor into the car. This was a nice realization because I used to fit the floor in through the door opening but that was difficult and required the door to come off. I'm not removing the doors until I weld in the quarter panels since they are perfectly aligned at the moment.
20190807_185744 by 7T02S, on Flickr

20190804_173342 by 7T02S, on Flickr

You can see that I already drilled all the plug weld holes. I'm pretty sure I did that 1.5 years ago! It's nice to see it back in the car!

Now it's time to modify the back "ears" of the floor that mate up to the wider wheel wells. I made some templates from a shoe box.
20190805_115708 by 7T02S, on Flickr

I did my best to transfer the radius with this curvature gage. It was too long to get all the way done into the lower section, so it just got me close.

20190805_130344 by 7T02S, on Flickr

Here's the transferred cut line.
20190805_123955 by 7T02S, on Flickr

Here are my marks and initial cuts. I am keeping the both sides of the flange but going to have to fab up a flange for the middle of the curve. I don't have a picture but I flattened out both sides and then bent the flange down 90 degrees to match my contour line.

20190805_142435 by 7T02S, on Flickr

Here is a shot with the floor cut on both sides. I got the cut pretty close, so that made me happy. I'm probably going to make a 90 degree flange on the sheet metal brake then shrink/stretch it to fit the curve. That can then be welded into the floor to replace the missing flange to the wheel well.
20190805_143933 by 7T02S, on Flickr


54 Posts
Discussion Starter #62 (Edited)
Weld B-Pillars

I also did my final welding of the B-Pillars to the Rocker Panels. I still have to grind down all the welds. I did plug and stitch welding.

Driver's Side
20190804_154055 by 7T02S, on Flickr

20190804_154111 by 7T02S, on Flickr

Here I added a few stitch welds and did some initial rough grinding of the welds with a 60 grit flap wheel. Note the black primer. This is SPI epoxy primer. I've read many people suggest brushing or rolling this onto flanges before welding instead of weld through primer. Seems to work quite well.
20190804_173637 by 7T02S, on Flickr

Passenger side. You can see a four spot welds I added that above the rocker line.I would have thought dynacorn would have welded down a little further than they did. You won't see epoxy primer in the joints on this side because I didn't take the pillar back apart before welding - that's because I finally got everything perfectly aligned and decided it wasn't worth taking it all back apart since I was more concerned about losing my perfect alignment with the door, window, wing window, and such. Once I get the car back on a rotisserie, I'll try and pour some primer into the joints.
20190804_173609 by 7T02S, on Flickr

20190804_173602 by 7T02S, on Flickr

I also welded the three plug welds per side shown in the middle of this photo on the B-pillar just above the door line. Dynacorn also didn't weld this joint. Maybe they couldn't reach the spot welder tongs into this spot and left holes to allow easy plug welding? Who knows but they are welded now.
20190807_185601_close by 7T02S, on Flickr

54 Posts
Discussion Starter #63
Removing Original Firewall and In With the New

I started thinking about the sequence of welding in all these panels. I decided that since I'm not going to remove the doors until I weld in the quarter panels to match, this will be my sequence:
1. Brace passenger A-Pillar and front of rocker.
2. Remove original firewall.
3. Brace drivers side A-Pillar and front of rocker while removing driver side torque box
4. Test fit new firewall.
5. Prep flanges of inner fender wells to firewall. Along with this will be epoxy primering all the flanges of all the parts listed below.

6. Weld in firewall.
7. Weld in floor.
8. Weld in wheel wells.
9. Weld in quarter panels, trunk divider, trunk floor, trunk rear brace, tail light panel, roof.
10. Replace front frame rails.
11. Repair front inner fender wells.
12. Replace core support.
13. Epoxy prime the uni-body.
14. Have more beer!

So, here's the start of that list.

1. Brace passenger A-Pillar and front of rocker. What's not shown here is removing the scissor jack that was previously supporting the rocker. It didn't provide much support since I had previously tied down the front frame rails down to my chassis jig. Before, the firewall was supporting the rocker all by itself really, didn't really need the jack but I need to be extra sure of the alignment of the rocker, both in height and rotation for installing the new firewall to the exact same spot.

20190805_162457 by 7T02S, on Flickr

2. Remove original firewall. Lots of spot welds to drill. Most were easy to get to though.
20190805_173222 by 7T02S, on Flickr

Look at all that rust in the flanges! It would appear, again, that the electrolysis dipping process I paid for didn't get everything... Although they did tell me they really had no way of know if they got everything.
20190805_175336 by 7T02S, on Flickr

3. Brace drivers side A-Pillar and front of rocker while removing driver side torque box.

Here I got to break out the plasma cutter. I first made enough cuts to install the square tubing bracing without reducing the integrity of the torque box supporting the rocker panel location.

20190806_181932 by 7T02S, on Flickr

More plasma cutting!
20190806_183636 by 7T02S, on Flickr

Don't forget to wear proper safety gear when plasma cutting. I had no idea I stepped on this hot wedge of steel and it melted directly into the sole of my boot!
20190806_184232 by 7T02S, on Flickr

Here's a clear view of the rocker bracing I added and the front end sitting all by its lonesome self - if you look closely, you can see the four spots I used to locate the frame rails. Eventually I'll be replacing those frame rails too and they should align nicely.
20190807_183602 by 7T02S, on Flickr

4. Test fit new firewall.

I had to unbolt the export brace to allow the cowl assembly to rotate up enough to let the upper firewall flange slide in place. Note I double vise-gripped the upper-rear corners of the cowl to B-pillers - this was to make extra sure that the cross dimension would stay put while I did this. I also fit the floor in and tested the match for the first time in the car. I have to say I'm very pleased with the fit. It's basically ready for welding the firewall and floor in one I prep the flanged and drill plug weld holes in the firewall and front floor edge.

20190807_190338 by 7T02S, on Flickr

I decided to test fit the new seat risers. The firewall is Taiwanese, the risers Canadian, and the one-piece floor is an American stamping - in case you were wondering. ;-)

20190807_190324 by 7T02S, on Flickr

I couldn't help myself and decided to clamp in the entire back of the car - and the roof. YEAH!!! It's moments like this that I really enjoy. I can see the end is in sight!
20190807_192344 by 7T02S, on Flickr

Looking like a car again! Here you'll see the original fenders and cowl.

20190807_192827 by 7T02S, on Flickr

Time to get flange prepping and welding. My goal is to have the entire unibody welded together by the end of August 2019. I think it's an achievable goal. Wish me luck!!!

54 Posts
Discussion Starter #66
Stitch Welding Frame

I decided to stitch weld the rocker panels and rear torque boxes. I had contemplated adding in the convertible inner rockers and components instead of subframe connectors but decided to just go the subframe route. I ordered a set of SpinTech sheet metal subframe connectors - they should be here this Friday!

To add to the structural stiffness, the stitch welding seemed necessary. I'm also going to add in a custom made gusset from the b-pillar to the rear torque boxes based on a brace that's present on the convertible. I'll add a story about that when I get to it.

Anyways, the stitch welding was also necessary before I epoxy prime all the flanges before plug welding.

Here's the passenger side after I completely welded it up. I tried to place the stitch welds staggered with the factory spot welds.

20190817_191148 by 7T02S, on Flickr

Close up where the torque box meets the rear frame rail and the leaf spring mount.
20190817_152254 by 7T02S, on Flickr

Underneath, I add some healthy welds to the leaf spring mount.

20190817_191210 by 7T02S, on Flickr

Driver's side.
20190817_152143 by 7T02S, on Flickr

Both sides.
20190817_191200 by 7T02S, on Flickr

Each side took about 2 hours of welding and 1 hour of finish sanding, for a total of 6 hours of labor.
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