Parting off

Graham Wright · May 2, 2019

I have recurring orders for batches of 5000 stainless steel rings. They are out from 7/8" OD 3/4" ID tube and are 2mm long.

Parting off leaves an internal burr which is not acceptable and has to be removed. This kills the profit.

Has anybody tried internal grooving at the part off point followed by external parting off?

The thought is to generate an internal groove that will coincide with the part off and avoid an internal burr.

Triaged · May 2, 2019

Are you using a sub-spindle to pick it off? If not you will just move the location of the burr.

FredC · May 2, 2019

Using a rotary saw for cutting off will minimize the cut off burr. Look here for ideas http://www.saw-lutions.com/systems.htm If a an attachment is too expensive or not available for your lathe you might get a couple of blades from them and build your own attachment.
If you are cutting off on a screw machine touching the ID with a double 45 degree tool before sawing off might completely eliminate the burr.

We used a fine blade saw to cut off .5 to 4mm hard stainless tubing in a mill. We hit each end with an internal bur bit then tumbled for burr free ends.

YouTube

For your much larger tubing I am sure a mill would be impractical, but doing it with a saw blade on a lathe or screw machine has been done successfully for many years.

Shop Supply Guru · May 2, 2019

Ph horn has exactly what you're describing. They have an ID groove at 1.5mm width that also has a chamfer so you chamfer the ID of the part as well.

Here's a link Horn ID Pre Groove and Chamfer 114

Graham Wright · May 2, 2019

Shop Supply Guru said:
Ph horn has exactly what you're describing. They have an ID groove at 1.5mm width that also has a chamfer so you chamfer the ID of the part as well.

Here's a link Horn ID Pre Groove and Chamfer 114

That's exactly what I was thinking off. The cut off part lands in a parts catcher. To avoid catching it on the internal tool, that would need to be withdrawn. I can't afford the time for a tool change (old Talent) but a double tool holder might do the trick.

Search

Largest Manufacturing Technology Community on the Web

Search

Parting off

Graham Wright

Aluminum

Triaged

Aluminum

FredC

Diamond

Shop Supply Guru

Hot Rolled

Graham Wright

Aluminum

Similar threads