I've taken a mig class at my local community college and now I want to learn how to mig weld tube bumpers, sliders and cages. The teachers there don't have much experience with tube so I'm looking for some good videos that can show me the right techniques to practice. For now I'm just looking for info on plain 1020 steel.

Successful tube welding is all about fit . Take the time to make good fits , tight joints good bevels etc. Dont weld too hot , make sure you have good penetration .

Hardest part I have found to be it being round you have to move a lot more an faster around that peice.

Like gunsablazin said, get your notches and nodes tight. That is the most difficult part. Measure several times. Steel is not cheap. If you cut too long its okay, because you can still cut it down. If you cut too short, you might have just wasted a 3+ foot piece of DOM tube ($$$).

There is a chop saw notching article by BillaVista that was very helpful for me. You can use a grinder with a cutoff wheel for more fine tuned cuts (several angled cuts). Also, holesaw notching can work well, but requires a jig. I don't think holesaw notching is necessary though.

If you have a complex node arrangement (several bars meeting at one place), you can use a paper towel carboard dowel or toilet paper cardboard dowel and use that to find the cut you need (trim with scissors). Then slide it around the tube you want to cut and mark the lines and cut the tube.

Welding the tube is the easy part. Getting good joints takes some practice and PATIENCE. Measure and take your time rather than wasting expensive tubing on bad cuts.

Charlie

Thanks for all the advice. I got a jd2 holesaw notcher a few months back. The first weld I'm trying to get right is a 90 degree joint where the notched tube is vertical and on top. My practice scrap is 1 3/8 x .125. My practicing so far has given me welds that either look nice and have no root penetration or welds that are just plain ugly. Can anyone point me to a video or some time lapse shots that show working and travel angles along with the start and stop points along a weld?

What welder, 110 or 220, what heat setting, what wire speed are you using? Flux core wire or gas?

I have a mm180 (its a 220V) and I've been running .030 with C25. I just picked up some .035 wire and tips too. I've tried several different settings so far.

My Miller 210 likes #3 setting @ around 35 inches for that size. Same gas/wire as yours. I bet your local JC might have a 'trades' library for a video to lookie-see.

You might want to check out youtube. They have quite a few "Mig Welding" videos. :smokin:

Well I haven't found what I'm looking for on youtube yet. Someone suggested that I take a look at Lincoln Electric's welding school. They do have a basic motorsports class that looked promising. I called them up and talked to one of the instructors. It turns out that they are not spending much time with mig anymore in favor of tig for the basic motorsports class. One of his suggestions was to try flux core to get better penetration and fusion at the toes.

I go to school for welding right now and they show some old vids from miller. Lots of them have some slow motion clips so you can see just how the puddle moves and the short circuiting action while welding.

Maybe try looking for videos by Miller on the web?

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