Cutting down chipped end mills?

[zoltan]

So I now have a collection of 4 flute end mills on which a corner or two have been chipped. I figured I should be able to cut or grind the end mill shorter to get to the fresh cutting edge and keep on using them (obviously they wouldn't be center cutting).

Is there any easy way to do this, or a cheap place to send them to get it done?

 

[tornitore45]

Is there any easy way to do this, or a cheap place to send them to get it done?

Depends where you are located, in Austin TX we have this

http://www.austintoolandgrinding.com/

Prices are on the web

 

[DJP]

I built a crude but effective grinder to sharpen the ends of milling cutters. You will need a cup stone and a holder so that all four cutters are at the same height. You will still need to relieve the centre portion. It can be done.

There is also no reason that a 4 faced cutter can't become a 3 faced cutter by grinding away the chipped face. It all depends on how fussy you are.

Lots of guys just buy new ones when the old ones get dull.

You have options.

 

[tornitore45]

[Lots of guys just buy new ones when the old ones get dull./QUOTE]

Yes but the broken end mill get re-purposed as a boring bar or a form cutter for the late or used as a dowel pin.

 

[Blogwitch]

Like everything else, if you want an easy job making of it my little machine does everything that you require, plus final gahing to make it centre cutting.

But as I said, it all costs. Mine is the smaller of the two

http://www.arceurotrade.co.uk/Catal...g-Module/EMG-12-End-Mill-Re-Sharpening-Module


John

 

[Hopper]

The cost of reasonable quality end mill cutters from Hong Kong etc is so low these days I doubt it would be worth paying a professional to sharpen your old ones.

You could take a look at Harold Hall's website and make your own simple indexing/holding device to use a bench grinder to sharpen your old cutters. I think he has all the details in his Workshop Practice series book on his custom grinding rest etc.

 

[Blogwitch]

I paid nowhere near the price advertised for mine, so a couple of hundred sharpened cutters paid for the whole unit. Well worth it if you are working together as a club.

In fact John S used to take his to trade fairs to show how well these little machines work, and he used to grind the ends back to flat when then were chipped up the flutes and they were like brand new when finished.

John

 

[Jasonb]

I've used the EMG-12 that Bogs linked to and it does a very good job of shapening the ends even if you cut off a damaged end and start from scratch. I sharpened about 40 cutters in a couple of hours and some of those cost £10GBP or more so would soon pay for itself. It is also so easy to use and setup, I think John Stevo has got it down to less than 60secs per cutter

If you are going to grind off the end and try to use the cutter then you need to do it at a slight angle with one cutting edge at the lowest point so the end of the cutter does not rub. I have done it to get out of trouble.

J

 

[deverett]

There is/was a Belgian guy Wilfried - ? (can't remember his surname) who demonstrated how it was quite easy to sharpen the ends of end mills freehand on an offhand grinder. Maybe not perfect, but in an emergency it would get you out of a bind.

Dave
The Emerald Isle

 

[goldstar31]

There is/was a Belgian guy Wilfried - ? (can't remember his surname) who demonstrated how it was quite easy to sharpen the ends of end mills freehand on an offhand grinder. Maybe not perfect, but in an emergency it would get you out of a bind.

Dave
The Emerald Isle

'Wilfried' -Still on the net and website is hosted by Skynet.be

 

[dalem9]

http://www.homemodelenginemachinist.com/showthread.php?t=17077 Here is how I sharpen my end mills