twentyover said:Think old dope and fabric airframes used to use linseed oil in the tubes to keep down internal corrosion. But I doubt you will be looping the TVR (on purpose), so maybe something like waxyoil or Eastwood has an internal frame treatment.
Th tube joint looks almost like acetylene welding- Using oxy-gas, mig, or tig?
I think I heard about the linseed oil in aircraft frames too. And I sure hope I don't loop the car!
The test joint I pictured above was TIG.
Yes, I would be extremely pleased with those welds. Way beyond what TVR did "back in the day"!
dherr (Forum Supporter) said:Way beyond what TVR did "back in the day"!
I've been pondering the original welding techniques on this frame, so I just did a little searching. Evidently MIG was originally developed in the 40's for aluminum welding, but got applied to steel shortly after. 1950's and 60's it was improved upon and by 1970 was extensively used in manufacturing.
Based on occasional spatter and the odd little piece of wire not removed, it seems pretty certain they were using MIG in the factory. This is probably all well documented in some book, so I'm likely not breaking any ground with this observation. But interesting to think about.
Long-awaited box from the UK:
Bushings!!
I had them custom made in red so that they'd match the engine mounts.
There are 24 sets for all the various a-arm pick up points.
Quick test fit:
More later!
Ok, I need about a million tabs, reinforcement plates, and gussets. My 3d model of the frame came in handy there.
I did some 1:1 prints just to check fit:
The back end shapes look fine. Here's one at the front:
I designed some little fillers that I hope to weld into those old wallered-out holes. See if I can reestablish some bearing strength there.
Time for.....
ROBOTIC FIRE!
Here's some of the end result:
I chipped off the heavy plasma scale, and then into the polisher they went:
I'll do a bigger write-up on the tumbler tomorrow, since I've fielded several questions about the process lately.
Ok, went out to check the tumbler this morning and found it to be not running. Color me not surprised. These things really are designed to beat themselves to pieces.
The motor was still hot to the touch, which makes me think it cut out pretty recently. Or there's a smoldering fire going on inside.
Maybe it just flipped an overheat switch in the windings. I'll try it again later. I could justify replacing this unit, but the same one is like $1500 new. I don't think I can justify that price-tag.
Here's the whole set-up last night, trying to destroy itself:
Some info on the set-up. Here's the water tank and recirculation pump:
The pump is a little unit that often gets used as a milling machine flood-coolant pump. It's a tough unit, and actually flows way more than I need. I have to choke it down to a drizzle. Like this:
Too much flow and you'll create a giant suds-mess. Ask me how I know...
I add about a cup of detergent to the 5 gal of water. Maybe you could use something more DIY, but this stuff flat-out works. Here's the enormous jug I had to buy:
Here were my steel parts after running for about three hours. You can see some of the parts are looking good, and others have large flat areas that aren't there yet. What happens is large flat pieces will stick together, and they need more time to finish.
And here's everything after "some amount" of overnight time. I'm happy with how they all ran. Faces are uniform and the mill-scale is gone. All the edges are smooth and slightly rounded.
Whoah, so you've got to replace the suspension mounting points, or reinforce them?
Nice Tumbler. does it come in black?
In reply to wheelsmithy (Joe-with-an-L) :
Black was a factory option. Rare special edition.
I am going to reinforce the existing mounts. Though talking it over with my buddy who does stress-analysis, I'm really making new mounts that piggy back the old mounts and take all the load. It gets nerdy fast...
In reply to TVR Scott (Forum Supporter) :
That's how I would have done it, but seeing your grind away tubing to install new tube in its place approach, I wondered. Looking great.
wheelsmithy (Joe-with-an-L) said:In reply to TVR Scott (Forum Supporter) :
That's how I would have done it, but seeing your grind away tubing to install new tube in its place approach, I wondered. Looking great.
The tubes I removed had rust all the way thru. There wasn't anything to reinforce.
Yesterday I fitted reinforcement insert "washers" to one of front suspension pick up points. The holes on the front lower tabs on both sides are significantly stretched. They're probably ovalized out about 1/4". The PO had tacked in some washers to help fix it, but I'm doing a deeper dive here.
Here I used one of my new plates to get the location for the inserts. At this point I scribed a line in the old tab to serve as an ending point for grinding. You can really see how stretched the holes are. Crazy.
First insert fitted, second side still needs a bit of grinding.
Here are both sides set up and ready to weld. I turned a 1-1/2" spacer block from aluminum to go between the tabs and hold the correct spacing. These tabs really are flexible, and bend with only small encouragement.
Front side zapped:
And back side:
Not exactly beautiful TIG welding, but I'll slide back into my standing-tig technique.
Got the first couple plates tigged in. They might need a little straightening, but they're close.
I'm loving the rotisserie now. Would have been awful trying to do this all in one place.
Another view:
So much stiffer than before! And I still have gussets to add.
These do take quite a while fitting up to the old, bent, blobby-welded tabs, but it'll be worth it in the end.
That looks great. So much better than what the factory did.
Beautiful welding! Im jealous of your skills. Someday the quarantine will be over and dad and i can tty out his new tig.
In reply to Dusterbd13-michael :
You know, it's all just understanding the process and lots of practice. Doesn't hurt clean the metal either...
Got a care package from Victoria British yesterday:
Ball joints, tie rods and steering rack parts. A big bag of stuff that might or might not work for the lower A-Arm to steering knuckle joint.
I'll admit to being in a pretty substantial funk for the last couple weeks, and I've had a real hard time getting out and working on the car. I need to try to get into the 30 minute routine or something, because fretting about the world and playing bubble-shooter for hours on end is clearly not getting the job done.
Just do one thing every day, no matter how small. It will likely lead to more things.
The Tig is looking great.
In reply to TVR Scott (Forum Supporter) :
My entire car hobby has degenerated into that same funk.
Pete
Hang in there. Things will get better. I was supposed to start a job search in March, but didn't even finish my resume. Family and cars are my focus for now.
In reply to TVR Scott and NOHOME :
well you berkeleys better get your heads screwed on straight and post more progress, because seeing the work you do motivates me to do more/bigger/better.
EDIT: that right there is me being supportive and encouraging.
Yup. Grab the munchkin, go to the shop, and let HER pick something to do. Anything, whether its the next step on the car or not. Remind yourself why this is fun, and create memories with her.
Dusterbd13-michael (Forum Supporter) said:Yup. Grab the munchkin, go to the shop, and let HER pick something to do. Anything, whether its the next step on the car or not. Remind yourself why this is fun, and create memories with her.
That's a good idea. She'd wanted to try out the new mini-belt-sander, and I've got about a zillion old tabs that need to be ground off.
Thanks for all the support. It really does help.
Nice welding and that tumbler is awesome!
Ok. I did some stuff for about an hour this afternoon. Ground down some poopy old welds. Did a little fitting of doubler-plates. Nothing interesting enough for a picture. But it's moved forward.
Whew.
That's how you eat that elephant!
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