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View Full Version : shars end mill cutter grinder head, any experience?



lowcountrycamo
11-30-2012, 08:25 PM
I noticed this shars cutter grinder head on ebay. They want 100 bucks more than new... err. Anyway, have any of you ever used one? How are em's held, 5C? I guess hardened steel bushings. I grind tips of ems on a cobbled grinder spindexer but the slide is too rough for flutes. Thanks for any help.

loose nut
12-01-2012, 10:56 AM
Picture or link would be nice.

Richard King
12-01-2012, 11:19 AM
I hope their product quality has improved. A friend bought 2 Shar's precision squares and both were bad.

lowcountrycamo
12-02-2012, 12:18 AM
I'm an idiot. I thought I put the link in. Should have proof read.
http://www.ebay.com/itm/END-MILL-CUTTER-SHARPENER-W-ALL-ATTACHMENTS-BUSHINGS-/270867662674?pt=LH_DefaultDomain_0&hash=item3f10f88752

The bushings and additional spindle not shown. Could not find on shars site but it's in there catalog in the vises section. 195 bucks at shars.

MichaelP
12-02-2012, 01:06 AM
Looks like an air bearing (if you're lucky) with a finger rest. Grinder is supplied by the customer. :)

I'd stay away. Shars is not a place I'd be buying air bearings from. Besides, air bearing is only one part of what endmill grinder should have.

oldtiffie
12-02-2012, 01:54 AM
http://i8.ebayimg.com/01/i/001/25/c9/2d06_12.JPG

That is not an air bearing but this is:

http://i200.photobucket.com/albums/aa294/oldtiffie/Air-quill/Air-quill7.jpg

But in theory and with enough care that "double ended steady" could be made to work but there would a fair bit of time needed and often a lot of frustration (and trashed end-milling cutters too)..

Toolguy
12-02-2012, 12:58 PM
As Tiffie says, that is not an air bearing. However, it may be better than nothing. If I were to try to use that for tool sharpening I would make six delrin pads to go on the end of the setscrews to keep the setscrews form having metal to metal contact with the tube. The adjustment of the screws is critical to get to the point where the tube slides smoothly but with no side movement in any direction. You can set the bottom screws to level the tube, then fine tune with just the top screw. The best you can do with this arrangement will not be as good as an air bearing, but then air bearings are usually much more expensive.

Mcgyver
12-02-2012, 01:08 PM
its use isn't obvious to me, it's not like any air bearing I've seen or used and why is does 'quill' not even remotely fit the two bores?

Has anyone used one of these? Pending a credible and strong endorsement I'd run away.

lazlo
12-02-2012, 01:22 PM
I've never seen one in person, but I've seen various Chinese importers advertising them as "running on carbide rollers."

In addition to the "Run Away!" advise: at the price Shars is asking, you can find a good used air bearing on Ebay.

JCHannum
12-02-2012, 05:42 PM
I have run across a couple of this type, but have never tried them. When set up, they have about the same feel as a plain bearing fixture, not nearly as free turning as an air bearing. They are a chicom knockoff of this Yuasa fixture, which is cheaper and probably much better than the eBay Shars copy.

http://shop.yourtoolingstore.com/Endmill-Sharpening-Fixture-Yuasa-550-002-MTS1591.htm

Better than nothing, but not as good as an air bearing.

MichaelP
12-02-2012, 05:46 PM
Looks like you hit the nail on the head, Jim.

I've never seen those.

lane
12-02-2012, 08:09 PM
I have used a dew if them . They have carbide ball on the end of the adjustment screws. They work like a air bearing just not quite as smooth. It all in how you get the 3 adjustment screws adjusted . If you do not have any thing else the work pretty good for sharping the flutes of a end mill.

Bill Pace
12-02-2012, 08:19 PM
While this fixture will do reasonably well in place of an air bearing, you have to remember that you will still need a grinding fixture that is capable of giving the many different angles that are needed to match the EM's original angles.

oldtiffie
12-02-2012, 09:51 PM
In theory and in practice too - with care - only the two bottom arms/rollers are necessary as they will/can act as a "cradle" for the quill under its own weight. The top arm/roller is only to keep it there.

If the ends of the arms are partial spheres the quill can be tilted up/down and/or moved left/right.

With a few well chosen accessories the item can be made to sharpen end milling cutter cutting edges - helical (side) and end.

I'd prefer to use a "Spindexer".

PeteM
12-04-2012, 10:15 PM
As noted above, the type shown is not an air bearing. The action simply isn't silky smooth and, in my experience, a poor substitute.

My own progression: 1) buy the cheap type shown, 2) replace it with a decent air bearing fixture, 3) realize it's a better use of my time to send end mills out for sharpening to a service with 10x better and faster equipment. The simple 5c collet fixtures with the angle reliefs built in would be a sensible place to start if you want to salvage some slightly used end mills. These touch up only the ends.