Reducing thickness of tool holder

At a car boot sale, I found a really heavy duty triangular tool insert holder. When I got home, I found that it would not fit in the tool post of my huge Herbert 4C Capstan Lathe. No Problem, - sez I, because I also have an old Denbigh Milling Machine, so I put in a suitable tool and tried to reduce the thickness, by slicing a bit off the top. I got a lot of smoke and sparks but very little cutting. I wonder how I can resharpen one of my slitting saws?!

The tool holder is pretty obviously hardened. So I rigged up a clamp affair on a heavy duty emery wheel and started to take small grindings off the top of it as the tip of tool has to be about 1/4 of an inch higher to line it up with the centre of the chuck. I have made a spacer to set it correctly, but about 4 hours of grinding, measuring, cooling, grinding, measuring, sweating, swearing, etc. I have only done about half. It's a big toolholder.

There must be a better way.

Does anyone know it? Please.

Thanks George.

Reply to
George
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Buy one that fits?

Take it to someone with BFO grinder?

Wally

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Reply to
Wally

Get a couple of the 1mm thick slitting saw wheels for a 4-1/2" angle grinder and slice the excess off.

For anyone who hasn't come across these they are bloody brilliant. So quick and without all the fuss of grinding everything away.

With a bit of care they are also neat. I chopped a 6" square out of a stainless water tank to remove the heater element which was spinning. Repaired the back and welded the same plate back in the hole.

.
Reply to
John Stevenson

Gordon Brown has to a large extent removed my ability to actually spend any money on anything other than essentials like wine and beer.

I have accumulated a host of useful things, without also acquiring a mechanical engineering background. I was a Mainframe Computer Engineer for about 30 years and that skill became useless within about

3 weeks after stopping doing it. The generous salary stopped about the same time.

Ho hum.

Reply to
George

Take the bulk off using a coarse wheel on a bench grinder and frequent dips into a water bath. When you're close to final size you can true it up again.

Reply to
Dave Baker

That's what he is doing.....

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Reply to
John Stevenson

Hi George When I had the same problem with a toolholder, I was able to use the bandsaw to remove the excess, then use an end mill to clean up the surface. It seems it was only case hardened, so by sawing off the bottom I only had to go through two thin layers and a soft(?) core, rather than get though a large amount of hard. As they say "it works for me" T.W.

Reply to
the wizard

They are great, and less than a quid each! I chopped 6" off a knackered 1" x MT3 drill to make a face mill for my X2 and it works well. Very little wear on the disk. Perfect also for chopping out the end of a piece of HSS if making a grooving tool. Far quicker than grinding it off.

Reply to
Richard Edwards

Use a solid carbide end mill. I bought a bunch of these, 16mm dia all used, cheaply from e-bay about

2 years ago. Had them resharpened locally for very little money, and I keep them in a draw for jobs such as these. Will cut hardended steel very easily.

Peter

Reply to
Peter Neill

Yes, that might work, however there is a lot of hardened steel to cut through. The tool is about 7 inches long and at least an inch wide. I should have tried that before I started grinding down the whole area. That was what I attempted with a slitting saw on the mill.

I do have a few of the smaller discs, I shall try one of them to see if it might do the job, this morning. There is quite a difference between the thickness of a tank and my tool holder! They do wear quickly when worked hard. Thanks.

Reply to
George

Hi All

Not come across these angle grinder cutters that have been mentioned, does anyone have a link to an image and seller of them?

I have to cut a large open a stainless steel pressure vessel (now vented!) Its a dewar - like a giant vacuum flask for holding a couple of hundred litres of liquid nitrogen. The two skins are about 4 or 5mm thick and have some kind of insulation material between them - some form of mica.

I need to cut through the outer skin to empty the mica and then through the inner skin to prove that it is empty and very definitely vented!

I had planned to do this with a 9 inch angle grinder and a small stack of cutting disks but am now wondering if these cutters in the small grinder may be a better option - if only so that I can open up a smaller hole in the inner skin.

Comments and group wisdom gentlemen?

regards

Dudley

Reply to
Dudley Simons

Here's an example, though you should be able to find them for about half the price, maybe from your local welding supplies house. I find them invaluable.

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Tim

Reply to
Tim Leech

Why not anneal the hoder to get rid of any hardening, mill it then reharden.

Jason

Reply to
jasonballamy

Or J&L ANBIB-03530E £0.84 ea until 17th march then std price £0.94 - BIB-3530E

115mm dia x 1mm thick x 22.2mm bore
Reply to
Richard Edwards

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Thanks Tim, I'll give my local welding supplies company a ring and see what they have.

Dudley

Reply to
Dudley Simons

On or around Fri, 14 Mar 2008 11:13:06 +0000, Tim Leech enlightened us thusly:

I've got some bosch ones, 115mm from the local hardware shop. also 1mm thick, and they cut quite nicely in mild steel and so on as well as SS.

Reply to
Austin Shackles

I once 'enjoyed' cutting through a stainless partition in a milk delivery truck using a grinder. Having done that once, I'd be inclined to find someone with a plasma cutter and pay them.

Wes

Reply to
Wes

You could anneal it. I get a number of cut offs from large boring bars we cut down to fit cnc lathes. I've checked Rc of a few and Rc42 seems to be the norm. I take the cut offs and heat them to red and let them air cool.

Then they are a lot easier to machine.

Wes

Reply to
Wes

Success!

I have done it, with only about 1/4 inch wear to the 1mm. disc too. I was very careful to mark it out and to hold the angle grinder exactly square to the cut and it only took about 15 minutes. I was amazed at how successful it was. There was very little cleaning up required also. I have only used these discs for cutting off rusted up nuts on exhaust systems before and they always seemed to get damaged and worn quickly.

It must have been due to the fact that I could see very well what I was doing and kept the grinder from digging in and very true to the cuts, that it was so easy.

Saved me at least 4 hours. Many thanks, I shall use this method again.

Regards George.

Reply to
George

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