1959 356A S/R coupe project chassis # 108625

[JTR70]

Tight weld joint I was shooting for.
Slowly tacking it together and making sure the edges where even with a series of clamps before each tack weld.
Entire run all tacked in.
Prepping the other side for final installation.
Both runs all tacked and tunnel in for a test fit before I commit to fully stitching it all up. So far so good.

Thanks for looking.
Justin

[Rimcanyon]

Justin, Nice work.

which welder do you use for tack welds? How many amps do you set it for?

[JTR70]

Thanks Dave!
I'm using my old 251 Millermatic . For sheet metal I run in about the 17 volt range on this machine. It will definitely vary depending how thin and rusted the metal I'm welding onto is. If its blowing through the heat is reduced.
The backside penetration of the weld tells me if more heat is needed. If the cut line at the butt-joint remains visible then the voltage goes up until it looks like the run in the above shot. That's the balancing act of getting it hot enough but not too hot...
Justin

[Rimcanyon]

Thanks for sharing the details. I have been using TiG for tack welds and butt welds, so I set amperage to 22A and I am good to go. But MIG is a different beast. I just bought a Hobart MIG welder, so I need to get my head wrapped around Voltage and wire speed. Your settings should give me a good starting point.

[roy mawbey]

Nice work Justin !

Roy

[JTR70]

Thank you Roy!

[JTR70]

Tunnel repair flange details:
Hammering in the relief shapes for the center rib to allow the tunnel to sit flush.
These long joint runs along both sides finally all stitched in. Now onto grinding them smooth. In small bites of course.
At this point I was ready to trim the rearward portion of the flange to final shape and width.
Once I checked with my original reference section I realized I had gone off track a touch. I assumed the flange sections overlapped for a stronger joint, but no. As you can see the rear portion was cut well short with a small window.
Lap section cut and copied to the original. Easy correction because the tunnel isn't mounted yet. So I'm glad I looked before I installed for the final time. Another example of the importance of a reference car if you want the factory details correct and just how easy it becomes to get off track slightly. My initial lap joint configuration is probably stronger and a touch more ridged but my job isn't to deviate and make "improvements". The mission is to replicate as best as I can the build details it originally came with from Reutter. Almost ready to install for the final time. Back to weld grinding...
Thanks for looking!
Justin

[JTR70]

Tunnel housing repairs complete. Final internal adjustments and confirmation before it goes in for good.
Entire flange repair runs finally dressed and completed. Note my handy T2 floor section to the right for confirmation.
All rust repairs and patches to this housing complete.
Very close to final installation time so its now onto prepping the inner surfaces for a sealer coat. While I'm at it I'm straightening and staging the wire loom tabs while I have a clear shot at them. Also checking to make sure they are still well attached. These are the small things you don't want any issues with after there is no longer easy access.
On the flip side, both the tunnel and these conduits were slightly tweaked so I'm double checking that the ends of conduits sit where they are supposed to.
My first clue was this poor fitment at this forward bracket against the tunnel wall. I also had issues with the ends of the parking brake conduits in relation to the center bulkhead conduit. I had to cut them free from this bracket and reset them. Again this is all small but critical detail stuff that has be right when its finally time to put it all together....and incredibly unpleasant and hard to correct once the tunnel is in.

[JTR70]

Again, thank goodness for reference examples so I could confirm approximate conduit height and placement.
Mocked up pedal cluster to confirm the clutch cable height.
Quick representative mock up of the throttle rod as it runs through that envelope
and lays across this forward bracket in a saddle relief which I had to add back in. This was part of dialing the final and correct height of this bracket.
And finally the ends of the parking brake conduits in relation to the bulkhead conduit.

[JTR70]

Tunnel both internally and externally set.
All the internal plumbing set and ready to go.
Rear flange connection points all within striking distance and will tack and adjust as it goes in for good.
Pulling this housing out one last time to paint and seal then drill the needed plug weld holes down the length of the floor. Decided the majority of the plug welds will be to the outside as it will be much easier to dress and smooth the weld heads instead of in here.

Thanks for looking.

Justin

[JTR70]

Final tunnel installation:
Inner surface sealed in semi-gloss. Tunnel housing now ready to go on for good.
Final floor preparation was drilling a "few" plug weld holes for the tunnel's flange. Again I'm doing most of the welding on the out side for ease of final clean up.
Conduits and floor section now sealed in a final coat of black.
Rear torsion housing bulkhead area thoroughly coated while I had a clearer shot at it.
Tunnel housing installed for the final time. Now onto back filling all those little holes...

Thanks for looking.

Justin

[Scott B]

Great recovery and resurrection of the tunnel Justin!!!

[JTR70]

Thanks Scott, There was a bit of effort invested in saving it but I always feel better about reinstalling the real stuff if its possible.

[roy mawbey]

Justin, what experience you have gained over all these years of 356 work. Did you tabulate the hours of welding up these jobs? Such a great job going on with this car.

Roy

[JTR70]

I appreciate that Roy! It continues to be a learning experience for sure and I think I've accumulated well over few thousand hours throughout the years by now. It sure feels like it anyway...

[JTR70]

Plug welding tunnel:
Working from the center outward. Starting inside at the floor pan lap joint rib.
Then it was onto the outside runs keeping the progress of these four quadrants even as it goes.
A tight flange joint is always priority number one. So far I've been able to leap frog about 3 holes at a time between screws for a nice tight fit. This process is painstaking and monotonous but no other way around it to ensure that the tunnel is attached to the floor thoroughly. Welding continues...

Thanks for looking.
Justin

[JTR70]

Tunnel plug welds completed:
Wrapped up the last these long plug weld runs out back here.
A lot of prep, welding and grind finishing yet to come but it was still very rewarding to get the welding portion completed. Very tempting to get lazy and do a single run of plug welds but...
the factory double rowed them for a reason.
Heat penetration at the top surface was checked as it went.
So glad I chose to weld from the bottom side. Grind finishing will be much more pleasant without the shoulder of the tunnel in my way. Some seam welding at both ends top side of this tunnel next. Almost there...

Thanks for looking.

Justin

[roy mawbey]

Alternate double row plug welds. You would think I would have noticed these before but I hadn't. Really good for strength I guess, but over a long run bet it seemed never ending filling all those holes !!

Roy

[JTR70]

It would have been so much easier to just go with a single row and it would have been okay but I went the extra mile here and just replicated the number of welds as closely as I could. Yes, a never seeming end of plug welds.

[JTR70]

Welding details top side of the tunnel:
As Roy just mentioned an endless supply of plug weld heads to finish. Taking this duty small bites at a time.
In between weld head grinding I went inside to begin the attachment mounts to the top side of the tunnel. Its tacked back into the same position where it was cut free; A very good sign.
Finished up with a gas welded seam and tack a found originally.
Forward end of the tunnel rewelded to the base of the toe board struts. Peddle assembly mocked up with locating rod installed to dial in the end of the clutch cable conduit for rewelding to the side of the tunnel. A slit was cut to help locate it but in the end I had to go a bit higher to achieve final alignment. Back to grinding.

Thanks for looking.

Justin