Sharpening End Mills

Pacer,

Tony is right, you almost have to be trained to grind endmills properly and get all of the relief angles set and cut properly on a endmill. I've done my share of endmill sharpening years back and come back to it and do it again 10 years later, its almost relearning it all over. Here's a couple of pictures of my setup on a junkie Tiawaneese tool and cutter grinder that Big Joe sold years ago. I kept this from the family shop dad had many years ago.

If you are still serious about endmill grinding I may make up step by step instructions on endmill grinding. Just for OD sharpening of end mills. I haven't perfected a good method for grinding the ends. Still working on that.

DSCN1356.JPG DSCN1357.JPG
 
That Deckel might be only for grinding little single edge small cutters such as are used in their pantographs (of which I have 1). But,I have a K.O. Lee "Knockout" tool and cutter grinder and an old but good non-air head Weldon outfit for holding the cutters. I didn't pay a lot for them. Got lucky. It'll also do smallish surface grinding,about 4" x 12" or less.
 
At over $4500 here in Canada I would expect this Darex E90 to be "a decent unit"!!! I too would like to be able to sharpen end mills (all edges) but know that possibility isn't going to happen for me any time soon.


Tony Wells said:
That fixture is only for sharpening the end of the end mill. It is an attachment for a surface grinder. The flutes require a fixture that allows the end mill to twist along the spiral edge of the flutes, with a small finger tracing the helix. There are also two angles involved there as well. A fixture could be made to do this job on a surface grinder too. End mill sharpening is not all that difficult, with the right equipment, but it's probably not practical for most hobby machinists.
Darex makes a decent unit:

http://www.darex.com/index.php?prod...e.pbv.tabs.tpl&option=com_virtuemart&Itemid=5
Click to expand...
 
george wilson said:
But,I have a K.O. Lee "Knockout" tool and cutter grinder and an old but good non-air head Weldon outfit for holding the cutters.
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George, that's what I have too (KO Lee & non-air Weldon fixture), but don't have much experience with it so far. Are you sharpening the ends with your Weldon fixture too or using one of the surface grinder type end sharpening fixtures? Are you routinely sharpening the flutes, or sharpening the end a few times before sharpening the flutes?

As an aside for the others, I wound up with three KO Lees - a BA900, a BA960, and a BA860. The first I bought pretty well tooled from a dealer at a fairly high price but competitive in comparison to what they're asking on eBay currently for predominantly stripped machines. I had been shopping for one and that one was intended to sharpen my end mills, and because I was curious to own one. The second was from a private seller who was moving and sold at a decent price. It came with a little tooling, but not much. It also came with a separate tilting KO Lee grinding head from another KO Lee (probably a 2060). The third I got for just over scrap value because the company was moving its operations to Canada. Only a partially intact universal vise was with that one. I could not get my money out of the first two unless I sold the tooling piecemeal. The tooling is probably worth more than the basic machine. I"ve been buying the past few years. I thought I'd never see prices like this again once the economy recovers, so I figured I'd take a chance and buy before most of them had gone to the scrap yards.
 
That little SO unit will sharpen all the edges, I'm just not sure about doing centercut end mills, or the possibility of building a mandrel to do slab cutters ir side mills. That model has been copied by the Asian market and is not too hard to learn. CNCcookbook has a short video on using one of the Asian copies here:

http://www.cnccookbook.com/CCBDToolGrinder.htm

Along with a nice looking Quorn homebrew to lust after. I'd rather have a K O Lee, myself, but I have my eye on a partially complete small Rockwell cutter grinder. If the price is right, I'll try to get it. Or not.
 
I have the Shares single point grinder, Knock off of a Deckel SO. It is typical Chinese quality with one major flaw in the quality control department. The casting that clamps the main assembly to the lower shaft has so much clearance it is nearly impossible to get it to lock. It is probably fixable but would require a lot of rework. The dials are pretty crude for setting angles. I use it for sharpening my lathe tools and making engraving tools. Works OK for that. Setting up to sharpen the end of end mills is tedious but doable. I don't think I could sharpen the end of any thing with more than 4 flutes. If it wasn't for the mis-bored casting I'd give it 3 stars. I'm not a machinist! I'd like to be able to re-bore the casting to a smaller size. I've considered taking it apart and trying to add braze or a bushing to the inside of that casting, Risky?
 
Larry, I also have the Shars single lip cutter. I'd love to share what I've learned, but you should probably start a new thread instead of reviving a dead one from 2012!
 
Tony Wells said:
That fixture is only for sharpening the end of the end mill. It is an attachment for a surface grinder. The flutes require a fixture that allows the end mill to twist along the spiral edge of the flutes, with a small finger tracing the helix. There are also two angles involved there as well. A fixture could be made to do this job on a surface grinder too. End mill sharpening is not all that difficult, with the right equipment, but it's probably not practical for most hobby machinists.
Darex makes a decent unit:

http://www.darex.com/index.php?prod...e.pbv.tabs.tpl&option=com_virtuemart&Itemid=5
Click to expand...




Jeez, $33,000 for a chinese drill sharpener ???? Just never understood how the people that set these prices like this can sleep at night???
 
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