I have to cut 32 pieces off a round tube, each 24mm long. The cuts have to be square across the tube. With RHS it would be easy - put a tee square across the tube and mark it off. How can I do this with round tube? I've done a couple by eye but when welded up look way off. I'm looking for less than 0.5mm runout.

take a piece of paper ( square ) wrap it round the tube so that the edges line up ( i.e. no overlaps at the sides ) mark it and cut.

Simples

Make a very simple jig from wood - like a mitre box. It would take minutes. You could even add a length stop - just push the tube up to it and cut.

Use a chop saw and clamp it so it can only be cut square?

Or get a chunk of steel with a hole the same diameter as the tube and clamp it (thinking slit down one edge and them use a vice to hold the tube and use this as a guide)

get a piece of tubing - Plastic/PVC would do - that will just slide over the piece you want to cut and use that as a guide for either marking out or for direct cutting against depending on method of cutting
(can jubilee clip it in place if you slit the guide piece - the guide could be faced off in a lathe if necessary)


Will try and use MSPaint to try and illustrate the above if my descriptions are a bit vague

Regards
Rob

Or wood as pointed out...


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Regards
Rob

Can't you find somebody with a lathe that could do them for you? Some one on here a perhaps.

More accurate and consistent.

[Edited on 19/6/11 by wicket]

What about one of these?

http://www.transtools.co.uk/store/prod_7914/plumbing-tools/steel-and-stainless-pipe-cutters/rothenberger-inox-no-30-stainless-steel-tube-cutter-3mm-30 mm.html

Or, get a bit of square tube which the round just fits inside.
Use that as your cutting guide.

Or, cut long to allow fettling.
A sanding station with disc and table would do this.

Lathe would be best if absolutely square is essential though.

[Edited on 19/6/11 by zilspeed]

Clamp a jubilee clip round the tube and use it as a saw guide.

IMHO the pipe cutter pictured earlier is the easy cheepo I mean 'Locost' answer.

But I seem to remember they cut better with a quick squirt of WD40 to the cutting wheel, helps stop the cutter from spiraling down the tube/pipe.

All good ideas. I quite like the jubilee clip one. Thanks.