View Full Version : How to flare EMT pipe.

Mr Fixit
06-10-2012, 01:22 AM
I have some of the HF cargo bars that I want to use for a spray booth wall system but they are only about 8.5' tall and my shop has 10.5' ceilings. What I want to do is use 1" EMT but the O.D. is to small 1.165x.070 wall thickness and the HF tubing is 1.220 that has plastic fittings on each end. I am thinking of flaring the EMT but not sure what type of tool I need to make on my lathe. I have a SouthBend 9" tool room lathe. Any ideas would be great.
TX Mr. Fixit for the family :)

06-10-2012, 01:53 AM
make a tailpipe expander


Don Young
06-10-2012, 11:36 PM
I have found that most of the "tailpipe expanders" are only intended to expand a dented or flattened pipe back to its original size and are not nearly powerful enough to actually increase the pipe size.

The simplest method of flaring or expanding thin wall tubing is with a swadging tool driven into the pipe. I have even used a socket wrench with a stepped OD for this but a long taper is easier to drive and keep straight. You can make one easily on the lathe. Just an end the size of the original ID and a taper to the desired ID. Grease well, insert, and bang with a hammer. If it is too hard to get the tool out, hammer around the OD of the tube to slightly expand it.

A muffler shop might have a hydraulic expander of a suitable size. They do actually expand the pipe.

06-11-2012, 12:06 AM
My experience with tailpipe expanders is the same. They are almost useless.

Mr Fixit
06-11-2012, 01:10 AM
Don thanks for the idea. If I understand correctly it's just a steel wedge that is sized to expand the pipe as you hammer it in, that couldn't be any simpler. I'm after some steel round stock Monday after work.
Thanks again. :)