How to weld a mild steel roll cage

[FM117]

I don't know what your taps equal in voltage but would
suggest the the wire speed numbers you posted will be way
out of the starting ballpark. I'd be thinking something
more into the 200ipm range to start with.

Edit
You want to make up some practice joints. Don't just do em flat
on a table, do them overhead, sideways, stand on one foot using
your left hand with one eye closed etc. Do em while your upside
down with sharp objects poking you in the ribs and back with
sparks falling down your neck and you can't really see the weld area.
These are real cage welding practice problems.
Dave P.

[tasslehawf]

You want to make up some practice joints. Don't just do em flat
on a table, do them overhead, sideways, stand on one foot using
your left hand with one eye closed etc. Do em while your upside
down with sharp objects poking you in the ribs and back with
sparks falling down your neck and you can't really see the weld area.
These are real cage welding practice problems.
Dave P.

Is there a practical welding test like this?

[Vicegrip]

I don't know what your taps equal in voltage but would
suggest the the wire speed numbers you posted will be way
out of the starting ballpark. I'd be thinking something
more into the 200ipm range to start with.

Edit
You want to make up some practice joints. Don't just do em flat
on a table, do them overhead, sideways, stand on one foot using
your left hand with one eye closed etc. Do em while your upside
down with sharp objects poking you in the ribs and back with
sparks falling down your neck and you can't really see the weld area.
These are real cage welding practice problems.
Dave P.

Add slithering in and out of the caged car about 20 times an hour too. Get in get placed and find that (fill in the blank) is not on/open/set right/pluged in/long enough or near you. Get out, correct issue, get in get set then get back out to welding hat that is sitting on top of the welder. Get back in and get right back out to answer the phone that is on the work bench and not in your pocket.

[FM117]

Vicegrip,
You got the idea, add about 95 degrees and plenty of
humidity, somebody that wants it yesterday
(and was dumb enough to tell you they bent/broke
it 6 weeks ago at their last event).
Dave P

[pro70z28]

I would suggest building a rotisserie. "Not just for hog roasts anymore"

[pull-do]

Is there a practical welding test like this?

Yes, there is, for process piping.

[Craig in Denver]

Edit
You want to make up some practice joints. Don't just do em flat
on a table, do them overhead, sideways, stand on one foot using
your left hand with one eye closed etc. Do em while your upside
down with sharp objects poking you in the ribs and back with
sparks falling down your neck and you can't really see the weld area.
These are real cage welding practice problems.
Dave P.

BINGO! This is exactly why I don't consider myself a real weldor.

[Speed Raycer]

The actual welding is about 5% of the time spent building a good cage IMO. Thinking, planning, drawing, cutting, bending, fitting, cutting, fitting, recutting, fitting and tweeking are about 90%.

This cannot be stressed enough. Think at least 3 steps ahead of yourself... it'll keep you from welding yourself into a corner... or more importantly a joint that you cant get the backside welded

[diverbill45]

I just read this thread and will agree with everything in the replies, but I believe that there's been one important thing that was overlooked and it will show up during tech inspection.

Creg stated that he wanted to use .095" x 1.5" tube for the roll cage. I would recommend that he get a rule book from whatever scantioning body this car will fall under and find out what the min. wall thickness allowed is. My point is, lets say, ......... the rule book says that the min. wall is .095", this will be where the problem lies. In the process of bending tubing, the tube will stretch and this will cause the wall thickness to become less than what it is when straight. If the rule book says .095" is the min. thickness allowed, then at most all the bends, in the roll cage, the wall thickness is less than .095" and the car can fail inspection. This is especially true when there are any 90 degree bends involved.

Having worked with pipe and tubing most of my life and also the building of a few roll cages, this minor point has been overlooked quite a few times by others, until you hit the tech inspections, and that's where you DON"T want to find any BIG problems.

You might want to check with someone in tech or somebody that does know if this will present a problem. I do know that when you bend pipe or tube something HAS to give and it's the wall thickness that does the giving.

Just thought I'd bring this up, because I'd hate to see all your work go to waste for something that was overlooked, during your time consuming build.

Hope this info helps.

Bill

[pro70z28]

Good point Bill. When I saw it wasn't an NHRA or IHRA cage I didn't mention anything because I'm not familiar with anything but those 2 sanctioning bodies. I know my mild steel cage is .118" minimum by the rule book. The tubing I purchased from Art Morrison was .134'. I bought some from a speed shop @ .124". Even the .124" you have to mic & be very careful with.