I was wondering if there is a method for cutting pipe to be welded together at
90 degrees. For a roll cage or something else.The only way I've ever seen is to use a cutting torch to sort of wing it, when making the curved cut to get the pipe snug against the other pipe.
Is there a technique or method for making a more precise fit for pipe welding?
Thanks.
You need a fishmouth, a round hole in one or the other. If in the end of the cross member, a semicircle (ideally). You can use a rigid mounted hole saw or end mill to cut it, or sand if you have a sanding belt with a radius, or just cut or grind. You could do worse than placing it over the pipe to be joined and scribing the cross section to be cut.
Tim
Tubing notcher
As well as the other methods mentioned, google search on this group for making paper templates to wrap around for torch or cutting.
I've seen a pencil mounted on a slot in a block. Forgot what they call it. Hold the pipe at the angle you want it to be against the mating pipe. Follow the block around the pipe and the pencil marks out the profile to make a flush fit. Takes some practice, of course, and you pick the cutting method that works for you. Templates work good, but take a bit more effort to do, unless you are mathematically inclined and/or plan on doing a lot of that pattern.
This is a cool item. Thanks Stephen, I'm going to make one of those!
walt
Use a hole saw the same O.D. as the pipe in a drill press to cut the pipe.
The chapest, yet reasonably precise and practical method is very simple:
cut the other tube in a right angle 45 degrees to its centerline.
I hope the little sketch will show how it works:
Tube 1
------------------- /\ / | \ cutting pipe to be welded together at
Goggle for "Winmiter" and "Tubemiter". Both are free programs to generate the paper template. Wrap around the tube and use a right angle grinder to grind the metal and paper away to the template line. Perfect fishmouth. I've even made double fishmouths, to mate a vertical tube at the junction of two horizontal tubes forming a +. I overlapped two offset templates and traced the bottom one on to the top one to make a double fistmouth.
Hasn't that been outlawed in Canada?
You can only use barbless hooks.
Gunner
"At the core of liberalism is the spoiled child - miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosphy of sniveling brats." -- P.J. O'Rourke
DOH!
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