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Premium Member
3,185 Posts
That's the way to resurrect a thread! :lol:

What I'm seeing in practice as I look more and more closely, is lots of examples 4 wheelers who do massive homebuilds and have horrifying looking tube welds... and that they do just fine.

There may be a shorter life span, there may be failures at lower forces than could otherwise have been achieved, but with the forces being applied on these things and the relentless beatings, failure would be inevitable with any weld... eventually.

For heavy use cages like that, the life of crush-repair-modify-remodify apparently lasts about 5 or so years, and then it's just not worth it to repair anymore.

At first I found this disturbing. I'm building for 3 years only to kill it in 5!? I think I went through all 5 stages of grief coming to grips with this! Now I just figure to start the next chassis build while the current one is still running. That way I won't miss a beat.

Personally, I think a lot of tube welds done in garage shops like mine are underpenetrated and the weld metal is built up too much. This is because of the difficulty in maintaining the proper angle between the electrode and the work as one works around the circle.

It typically gets done as a series of 4 pseudo-flat welds. Maybe the first and possibly the middle third of each of those 4 passes has a good electrode angle. The bead ends when the electrode angle OBVIOUSLY SUCKS. Therefore every tube weld is a series of starts and stops with crappy angles and more globular transfer than penetration.

However, most people are properly paranoid about this and design in order to compensate. I'm not sure yet whether that's good or bad, but there it is!

Apparently laying up a bead that's over an eighth inch thick on eighth inch stock, with superficial fusion of parent and filler metals is at least better than "totally worthless".

Perhaps it's not totally nuts to even forget about fully penetrated welds for tubing. After all, the inside isn't backed up with shielding gas and if the metal inside heats to molten, it's going to burn, and the oxide is going to get drawn into the weld, damaging the resulting structure. A thicker fillet with good fusion may be like a sort of attachment bracket, supporting the joint just fine.

So, how does one do it best?

SCORE regulations apparently spec a TIG welded roll cage, which makes sense since those nutballs are bombing across the open desert at 130 miles an hour. They can't afford the liability of anything other than the proven best.

With TIG, the parent metals can be more deeply melted with a more controlled admixture of filler. The tighter angles can be welded inside of with more electrical stick-out on the tungsten and a "gas lens". Most interestingly, though, a shielding gas can be used to PURGE oxygen from the inside of the tubing prior to executing the weld, so that a full penetration bead isn't drawing up oxide from the back.


Interestingly, as I'm now 18 months (hopefully halfway or beyond) into a build, my skills have improved but my ability to remain concerned for the outcome has become fatigued. I just want to wheel the darn thing. I know it's going to break... often... and it's hard for me to care enough to keep the quality up when I know I'm going to be ruthlessly beating the thing as soon as I possibly can.

So... yeah... tube welds can suck.

However, it sucks worse to be welding when you really want to be wheeling.


Full -N- Down
641 Posts
Now that kind of makes sense to me, I didn't really buy the new welder for the sake of welding. It's actually in anticipation of the things it will allow me to do to a new wheeling rig, so I can fully understand that at some point you just need to do the best you can and move on.

I spent a lot of time reading several "welder" forums prior to my purchase so I've become a bit skewed in my mindset.

I just spent about 30 minutes laying some welds down on 3/16" flat bar after dinner and even at 110v and approx. 90amps with 0.30 flux core wire (spent my discretionary funds for the month on the MM211 so I have to wait until next month for gas :D ) it certainly seemed to have plenty of penetration or what ever you want to call it. For the newbies out there, I was able to make what I would consider one respectable pass out of 6, which by my estimation is pretty good for a newbie. At least i'm happy with the results. I've got a lot of practice ahead of me, but these MIG/Wire feed welders are certainly much easier to start of with than the old stick welder I learned to use over a decade ago. Never was very good with it and my welding consisted of pass after pass on top of each other to build up thin spots in 36" pipe on a trailing suction hopper dredge.

The other big difference is the auto dimming helmet, I'm extremely happy with it and don't know how people got along without them. Highly recommended!! They seem pretty common place now days, but flipping the freaking hood down prior to striking an arc was one of my biggest problems with the old arc welder, that and the engineers screwing with the amp setting while I was 100ft. into the pipe requiring me to crawl all the way out, reset the welder and then crawl all the way back in. Duck waddling in 36" pipe with full welding gear and the Singapore heat was definitely a chore. More than one of those engineers woke up to find their work boots epoxied to the deck :D

4,348 Posts
I would go with the mig welder. I had never welded in my life and a friend of mine got a mig welder and let me try it and I layed down dam near perfect welds right off the bat. I was told it is 90% prep and 10% weld. Ground down the pcs. to be welded and let it rip and it came out fantastic. So when its time for me to buy a welder its mig all the way.
101 - 104 of 104 Posts