Lathe bevel pipe stub for weld practice

May 20, 2010 2 Replies
R

Hi everyone



To use lathe to machine a prep, the bevel, on the end of a short piece of pipe for practicing pipe-welding - what is a secure way to grip it in lathe?



Would hope to take the same pieces back to the lathe repeatedly - can plasma-cut apart completed welds.



Took pieces of my 140mm dia by 10mm wall-thickness pipe (about 5~1/2" dia by 3/8" wall-thk) to a lathe. But guy rightly nervous - smallish



3-jaw chuck wound outwards to grip pipe internally on outer steps on chuck-jaws - but like "hanging on by fingernail ends" and pipe pieces about 200mm (8") long.

Obviously, my mind can throw up ideas like - weld three small blocks to the bore of the tube at the chuck end so that you can slide in a near-internal-dia disk with a drawbar which goes right through the headstock and pulls on the back of the spindle. Etc



What does anyone really do?



Rich Smith


Vote
Twitter Facebook LinkedIn
P

Turn a plug with a small flange to fit inside outboard end of pipe, center drill, and use a live center to support. Isn't there usually a small straight cut at the inside before welding? The flange could be that dimension.

I have a bull nose center, but not that large. A bull nose would work well as long as you were careful with the cut. The bevel precision would depend on the precision of your cutoff procedure.

A steady rest could be used, but the o.d. is often rough.

Pete Keillor

Vote
Twitter Facebook LinkedIn
B

Hey...by the time you get that pipe jury-rigged to the lathe to run a bevel, you could have used a grinder to do 3 or 4 of them. If you've a bench grinder, it's quite simple to set the doggone rest to the proper angle for the bevels you need. Otherwise, it's going to be easier and safer to jig up a grinder than a lathe. Just my 2p YMMV IMNSHO ETC

-- Big Ben BS266 the "sometimes the old way IS the easy way" Slug

Vote
Twitter Facebook LinkedIn

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required