ARGH slotter woes

I just gave up for the day on a machining project, first time this has happened in years.

I'm trying to use my Bridgeport slotter to cut a 3/32 keyway in a 3/8 shaft. I keep advancing the tool and not cutting metal.

All slotters and shapers have a clapper that lets the tool give way on the return stroke. After quite a while, I determined the clapper is giving back and not snapping back forward on the cut stroke. I've tried tightening and loosening, no joy. The spring on the clapper is not very strong, you can move it back with your finger out. Should it be far stronger?

Or maybe I don't have enough relief and rake angle. What's right here? I'd pull my hair out over this, but I'm already bald.

I should say, I use this tool about once every five years. So, I'm not very proficient. I may give up and buy a 3/32 broach. But, I think a broach may not work either as the keyway is 1.5" long, or too long to broach easily.

Karl

Reply to
Karl Townsend
Loading thread data ...

In a _shaft_ or a gear? It sounds like a gear ... why would you use a slotter for a shaft?

Bob

Reply to
Bob Engelhardt

I assume this is vertical. I would clean it and oil it. Then tighten it, but that shouldn't make the clapper swing any different. Then the spring has to overcome gravity and close readily. Advance and it should cut. The only back stroke problems I've had is carbide which breaks.

SW

Reply to
Sunworshipper

I can't speak to the specifics of your machine, but chances are that your tool is heeling and pushing itself out of the cut. Put some dychem on the back of the tool and see if it is rubbing off on the cut.

Paul K. Dickman

Reply to
Paul K. Dickman

Yes.

I've always just locked the clapper in place.

Reply to
PrecisionmachinisT

First a correction, I'm cutting a keyway in a pulley.

I went to a huge relief angle, 12 degrees. And a large rake angle, 15 degrees. Then PUSHED on the clapper.

Job completed. Only took four hours to cut a 3/32 key 1.5" long.

Karl

Reply to
Karl Townsend

If all else fails use a cold chisel like they did back in the old days.

Reply to
PrecisionmachinisT

(...)

This is the close of the cutter clapper caper?

--Winston

Reply to
Winston

LOL, good one.

I suppose. In theory, I should tear it down and fabricate a new clapper spring. Won't happen. Pretty sure parts are unobtainium for this unit.

Reply to
Karl Townsend

Ya know, on my logan shaper there is an oversized washer that slides on the edge of the clapper. Adding a washer wouldn't hurt in your situation thus shortening the spring space.

Clappers can be fickle at times, I like the planer one that the tooling is so heavy there is no need for a spring to close it. But, it needs $50 of hydraulic oil, bummer.

SW

Reply to
Sunworshipper

(...)

Their site lists 8219 parts for sale.

formatting link
'search' feature doesn't work for me but it's a free phone call or you could click on the 'Live Support' dialog box in the top right corner of the screen.

What's the worst they could say? You might be pleasantly surprised! :)

Call 800-843-8801 # 7140 E-Mail snipped-for-privacy@hardinge.com

formatting link

Hardinge Inc. One Hardinge Drive Elmira, NY 14902-1507 USA General Information: 607-734-2281 Sales: 800-843-8801 Sales Fax: 607-734-8819 Workholding Fax: 607-734-3886 Service: 800-424-2440

--Winston

Reply to
Winston

Is that a copper clapper cutter caper? ;-P

Cheers! Rich

Reply to
Rich Grise

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.