LocostUSA.com

Yep, like he said... It's easier in the long run, and your T-shirts will be cleaner, if you go ahead and clean up the parts you're going to re-use later. Added bonus is that if there's a broken/damaged part, you'll find it now instead of when you're putting the Locost together and want that part to work.

Good work, Bro! Keep after it!

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JD, father of Quinn, Son of a... Build Log
Quinn the Slotus:Ford 302 Powered, Mallock-Inspired, Tube Frame, Hillclimb Special
"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom

I'm finally getting ready to build the frame. Pretty exciting. I've completely stripped the donor and the chassis left the premises last week on a flatbed trailer. I've now got room in the garage for a build table. I just have to figure out a way to get a couple sheets of 4x8 MDF home from the hardware store.



In preparation for frame construction I set up my new Miller 140 and practiced with it for several hours on Friday, and again earlier today. I wasn't nearly as good with it as I thought I'd be. My welding experience is limited to a class I took at my local CC about two years ago, but back then I got to where I could make a pretty nice bead in 16GA steel with an oxy-acetylene torch. With the MIG welder I couldn't even get close to that.

I think the main difference is back then we used dark goggles and I could see the puddle, the torch, the work piece, and everything else. With the auto-darkening helmet I could see the spark, and that's about it. After experimenting with lots of different angles and work piece positions, I eventually got to where I could see the puddle pretty well, and the work about half the time. So half my welds look okay, but the other half wander off the mark.

The good news is I can stick two pieces of 1" square tubing together pretty well with 4 tack welds. I think I'm fairly well-qualified at this point to tack the frame together. I'm not sure I'll be ready to fully weld the frame after that. I'll keep practicing and watching YouTube videos, but at this point I would gratefully accept any and all hints, tips, tricks, and offers to come over and weld my frame.

Practice is good. Consider only welding one edge of the tube. Then you can bend it to break it off and get an idea how you did. You can use less tube that way. Also you can weld all four sides then cut it off close to the welds and weld the same piece on again.

Maybe your helmet is too dark? Can it be adjusted? Being able to see what your doing seems like a big help to a beginner like me. I also found reading glasses help, even though I don't normally use them for reading. Also powerful shop lights like those halogen ones on little stands might help.

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Our auto helmets at work are almost like 'daylight/shoplight' before and after the spark.....only goes black at the instant of welding....

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gblawson (Gordon)
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http://gblandco.com/gb/cent/cent.html

Nick
The solution is to add helmet lenses with magnifiers. [did not ask how I know] Your local welding distributor should have them. The lens come in standard helmet lens sizes. They are strength rated by your age.
Dave W

The auto darkening helmets should be adjustable... I've never really been a fan of the auto helmets...

Also, based on someone else's recommendation on the site (apologies for forgetting who ) I bought a tripod-mounted 2x500W halogen shop light on sale. 35 bucks at Canadian Tire - I imagine the same at Harbour Freight. With this, I have a MUCh easier time hitting the joint.

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Warren
Isuzu Pickup/SR20DE, +401 COLD frame
Build Log: viewtopic.php?f=35&t=11601

Boy I need to look into this. I'm teaching one of the younger guys here at work how to TIG weld and I found that I was having a tough time seeing the weld. Even with my new bifocals, I really could use some magnification. It's fine if I'm welding thick stuff but I start trying to lay down a nice bead on some thin wall tubing and I just have trouble seeing well enough.

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-Keith

I've been practicing every day now with the MIG welder and I've reached a point where I've gotten pretty consistent. The beads are bigger than I'd like but at least I'm melting the metal all the way through to the other side. I found I can see what I'm doing a lot better if I get my helmet really close to the work.

Encouraged by this progress, I finally took the big step and started tacking together the frame. I had to start with the nose because I still don't have a build table yet, and I made a jig for the nose back in January.



Pretty exciting, my first real welding, even if it isn't actual welding yet. I'd originally planned to tack each joint in 4 places, but with the L-tubes in the jig I could only reach two seams on top and one on the bottom. When I pulled the work out of the jig I was amazed at how strong it was with just 6 tacks. I was also amazed at how straight it was, all sides completely parallel, and I was pretty sure that if I tried to add any more tack welds it would never be straight again. So I'm leaving it alone until the whole frame's tacked together.

Nick,
May I offer suggestion? When I am tacking square tube together, I tack on the corners. That way when I come to finish weld, I get a nice continuous bead on each side.
Cheers,
Stewart.

Your front frame looks excellent. Nice jig too.

The "where and when to tack" issue does turn out to be important. I had to work through that myself because I underestimated the power of tack welds to move the tubes around if you: 1) do them at the largest fit-up gap first; 2) apply too many (especially more than one on a side before doing the other faces); 3) make them too large.

Since you're practice welding right now anyway, you might want to do some experiments with tack welds on thin scrap metal, or better yet, some cut-offs from your chassis tubes. You can hand file to make some poor fit-ups an see what happens when you do various things like 1-3 above and try to keep one tube square to the other or at a specific angle like 30, 45 or 60 degrees.

Now that I'm slightly smarter (only just slightly) I can pretty much keep things aligned. Even if you do tack in the center of the faces, you can file or grind the tack down to a minimal size and then your final bead will look nice because the arc pretty much plows through the tack weld like base metal when it's small enough. I don't think it makes much difference visually or structurally when you make the tack small.

There are circumstances where it may not be easiest or best to tack in just one specific place (face center or tube edges) just due to the physical situation.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Turn down the feed rate a bit. It looks like you welds are built up to high. I welded my whole frame with .023 wire. I think it also helps to line your shoulder up with the weld. Helps to keep the weld lined up with the bead. THe good news is you'll get really good by the end of your frame build. (I did). On my car, lets just say it's a good thing the back end of the frame is covered up.

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1998 E 300 Turbodiesel
2006 Jetta diesel
1995 C3500 purple diesel bucket truck w/yellow & silver flames

Hope who ever got your donor will put it to good use. On the east cost, that car would be considered pristine!

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1998 E 300 Turbodiesel
2006 Jetta diesel
1995 C3500 purple diesel bucket truck w/yellow & silver flames

Thanks all. I know I'll get better as I go along. I'd almost have to. One thing my welding instructor taught us was to start each welding session by running a few beads on scrap metal, so I plan to keep practicing a lot. I've found that butt-joint tacks are definitely easier than tee-joints, and angled tee-joints are the worst on the acute angle side. I don't think I'd ever tack that side, and even welding there seems more like building a giant fillet with melted wire.

I can definitely see that tack welding moves the tube away from a right angle, but I also see that tacking the opposite side seems to bring it right back to true. In the jig the tubes couldn't move at all, but I could hear the wood creaking as the joints cooled. Still pretty surprising that it came out of the jig straight, although I can imagine that stresses are now locked into the structure forever.

I learned early on that you can't MIG weld over a giant tack bead. You can with gas, and probably TIG (no experience there), because you can hold off dipping the rod and let the bead melt into the puddle. MIG just makes a big mess. So I got in the habit of grinding down tack beads before trying to fully weld the joint. It seems like I practiced as much with the angle grinder as I did with the welder.

My Miller 140 came with a 4" roll of .030 wire, but I got a giant 8" roll of .023 at the same time and that's what I'm using. The wire does come out pretty fast though. I don't actually set the wire speed, just wire thickness and work thickness, and Miller figures out the rest. No doubt Miller thinks I'm a really skilled welder.

Yeah, even the battery boxes were intact. The floor panels were gone, though.

I asked the guy what he thought he'd do with it and he said it might go to England. That would be pretty cool. He also said the only reason it was worth anything was because it was a chrome bumper car. He said he couldn't get a dime for a rubber-bumper car.