got the R90 out in the sun

[8ninety8]

Well the welder did say they'd never leak, maybe I'm getting too anal. I'll think about it for a day or two. Yes, it's tig welded. Thanks John.

[melville]

Was rolling over this morn when the thought pops into mind, if there's leak after welding the whole thing together, and fuel has been introed into tank, then there will be fuel in the gap between the welds, and the torch will light up the fuel!

Sometimes a seemingly great idea, making the tank back superstrong, can lead to unforeseen consequences.

So, just going go ahead with What I first did, make the back with fewer pieces, fewer welds, and no overlapping joints. Will hang this piece on wall as a conversation piece, I think I can pound out the two new pieces fairly soon using what I've learned.

I knew there was reason I never saw a lot of welds on the various tanks seen!

Just yesterday in welding class, a guy welded two plate squares together all around the edges (doubling their thickness), then tried to practice welding beads on the surface.

He'd gotten a good weld on the edge, with no leaks until the wee bit of air trapped between the plates made its own leak with a BANG!

[jstrube]

Well the welder did say they'd never leak, maybe I'm getting too anal. I'll think about it for a day or two. Yes, it's tig welded. Thanks John.

That is why you pressure test it. I MIG welded tank for my Bronco years ago. MIG leaves lots of porosity, I had some very small leaks, but the POR 15 cured it just fine. It was steel and way before I learned to TIG.

[8ninety8]

Tired of working on tank bottom, decided to start rounding off the top side.

[8ninety8]

Will split the top side into two parts, if it works out. Every move is new territory. Really hard work.

[8ninety8]

Back to the gooseneck. First side attached. Can't believe it's gonna have nine pieces. Just too many curves and bulges to shape out of one piece. Labor of love or insanity. Appointment with psychiatrist tomorrow. Shaping front socket and checking all stock clearances, looks feasible.

[lmo1131]

Appointment with psychiatrist tomorrow.

Don't forget to take your leather bag and a mallet along... ..

[8ninety8]

Except for obsessive/compulsive disorder, pysch. said all is normal. A couple more pieces almost finished. Over a foot of the white stuff should keep me in the garage for awhile. Smooth outer skin is gonna be a pain. Bulges seem to be easy by comparison. Never got the leather shot bag, just pound on several layers of old carpet, and various maple anvils. Gotta keep the cost down. Thanx for annealing tip, now using a 1200 watt heat gun, seems to work without lighting a torch.

[20774]

I'm having trouble visualizing where you're going. It looks like this is a cover for a Forumla 1 rear engine. Or the housing to cover the engine for a sidecar racing rig.

[8ninety8]

I see you're up to your elbows in a teardown, but it's that time year. You know where I'm going, an aluminum 16 gauge fuel tank that looks straight out of the fifties Brit options handbook. May have to scap it if it leaks, but what is a hobby for if not constantly improving the breed? The dimples can be plainshe'd out, smoothed and polished, and roundal applied, on the topside.

[lmo1131]

I'm having trouble visualizing where you're going.

FrankenTank!!!

But then this is the interior/underside ...

[8ninety8]

That's what appears to be happening. The outside is getting hard to shape. Made a big dimple on bottom of stump to help out. Probably not post until it's done, if ever, riding into the fog of the task.

[8ninety8]

OK, one more. Here's what the big dimple can do.

[8ninety8]

Out of sequence, but here's a big fat wide top with plenty of bulge beginning its form. And here it is with a pretty good bulge, maybe coax a little more after it's fit up to the edges.

[8ninety8]

Had a piece of extruded tubing 25mm D, figgered why not reduce it, cut 20mm threads and attach standard karcomas. So, not having a metal lathe, hand held the piece against 2 and a quarter by 80 inch edge sander until D is approximately 20mm and then cut the threads. One thing at a time. STill thinking about type of filler. The pipe came from an extra mounting stud spacer from under the trans. Why not use it for something constuctive? Also tried a 13mm nitrile rubber O-ring in place of the fiber factory washer. Might work out. Ethanol might be a problem.