Tool and Cutter Grinders.

Rik Shaw. I think you are right about the Keller cutter grinders coming over from the States. Where I served my apprenticeship we had two Kellers one prewar and one that was possibly wartime. Both had there own cutter grinder. When the place closed down a friend of mine also an ex apprentice bought one of the cutter grinders, this is the machine I have access to. I tend to go over to his place two or three times a year for a sharpening session and have not bought a cutter for years.

I had a go at this with my Stepperhead lathe, the biggest problem was working out the helix. I guessed the cutting angle by setting the diamond grinding wheel height. It worked but it was a lot of setting up. How would you sharpen say a 2mm end mill flutes, just buy a new one? https://www.youtube.com/watch?v=yMxv1jU-R_A

Alan

Alan - I would not bother sharpening flutes on anything under 10mm. dia. Just replace it is my advice.

Hi Alan,

I sharpen a lot of cutters all the way down to 2.5 mm dia ,they are easy to do,have sent you an e mail with attachment with some information.

John

Careful Alan with the praise or some on here will think your are another of my sock puppets.

But in answer to your question, yes Doncaster is still on the cards for 2017. I spoke to Lou Rex at the end of this show and he's quite happy to have me return. At Doncaster this year we did just over 300 cutters, didn't count the drills, in the 3 and a bit days as we started on the Thursday afternoon for the trade.

However I'd like to address some of the other questions that have come up. From doing this grinding at shows and also demoing the EMG12 and EMG20 I have learn a lot, more about people habits that about grinding.

And yes if you don't get thru £800 worth of cutters in a lifetime then the expense is hard to justify. A bit like wanting a Bridgeport when you only make 'O' gauge loco's, hard to justify.

However after answering that no the EMG12 and EMG20 can't grind the flutes, [ Think I'll get a placard for next year ] the majority of people accepted that grinding flutes would not only leave them with an undersize cutter, it would leave them with a cutter they had no idea what size it was.

One thing brought home to me very rapidly last week wasn't about the machines [ got loads ] or the skill [ been able to freehand grind most cutters for years ] but circumstance.

I needed a small dovetail cutter for a new door lock plate on a Ferrari [ not mine ] OK no problem got one, but when I came to do the job it was larger than I remembered. OK no problem, grab a 2 flute slot drill, grind one flute off and then grind the dovetail up. Only be used 4 times in alloy and 4 times in nylon so no big deal.

Now 4 weeks ago I went for an eye operation which worked out fine. What isn't fine is my eyes are now completely different prescriptions and not even the same and will be like this until they have settled more and I get new glasses.

Result is I can't see to sharpen this cutter. Pulled the Vertex unit out and did 5 and took a chance on one working. It was No 3 BTW.

Point being with a lot of people on this board being same age as me or older I know I/m not the only one.

Hell some on here can't even see to get in the workshop, let alone make anything. So it doesn't matter what you have if you can't see, or see well enough. Funnily enough I can use the EMG's as all the skill is in the machine, not the user.

Now getting onto CNC. Doesn't matter now but for a while I had a CNC milling cutter grinder on the go for a while but the advent of us getting the Chinese to modify an EMG to working format means that there is no point carrying on. My time is better spent elsewhere.

It's not hard, in fact it's very easy as once I had drawn the various size of cutters up in the CORRECT relationship to the wheel the light bulb came on as regards programming.

You don't need shed loads of programs for each size cutter. In the 2 flute range of 3mm to 6mm there are hardly any differences in angles when presented to the wheel, we are looking at 20 minutes difference max. Then like gear cutters it moves in bands 6mm to 9mm, 9mm to 12mm, 12mm to 14mm, 14mm to 16mm, 16mm to 18mm and 18mm to 20mm.

So 7 bands or different programs for 2 flute, same for 3 flute and same for 4 flute, so 21 programs will do all the popular cutters, metric or imperial. The programs are easy, I hand coded the first few as they are under 20 lines of code but once the code is written anyone can use it. No one has to reinvent the wheel.

Hope there is some food for though here.