Another end mill sharpening question

[oscer]

Hi folks, this question is similar to the one Sammthedog just ask about the deckel tool and cutter grinder. I did a search and read a little about sharpening end mills and I saw some folks interested in a tool grinder from Northern Tool, a copy of the deckel for about $600. I'm thinking you could get your money back pretty quickly considering the price of end mills. My question pertains to the attachments, I see a long list of pricey add ons in the grizzly catalogue but I didn't notice any in the Nothern cat. The grizzly unit is now made in Tiawan and is priced at about $1600. Could I get some reviews on the Northern copy? Could you get similar results from a surface grinder? I don't own one but it is on the long list of tools I'd like to add to the shop, probably would be a lot harder to set up for sharpening though than the small tool and cutter grinder.
I don't want to do any grinding on my mill or lathes. Thanks oscer

[ronm]

Oscer, I was about to ask the same question in the other thread, when I saw your post...Harold, & the other grinding gurus, how about this one? Obviously a Chinese Deckel knock-off, but I've always had good luck w/Northern's stuff quality-wise...
http://vi.ebaydesc.com/ws/eBayISAPI.dll ... 1&caz.html

Edit: never mind-read the reviews here:
http://www.northerntool.com/shop/tools/ ... _200414732

[samthedog]

I didn't realize my post would spark interest in sharpening. I am curious about the flexability of a single lip machine because I have heard many people sing their praises. I am just curious what extras are needed other than the collets.

Paul.

[oscer]

I didn't realize my post would spark interest in sharpening. I am curious about the flexability of a single lip machine because I have heard many people sing their praises. I am just curious what extras are needed other than the collets.

Paul.

Hi samthedog, I'm wondering the same thing. I didn't want to change the direction of your thread to the cheap china imitations. Been looking on E-bay but no deals like you have found I would jump on it.

[oscer]

http://www.ebay.com/itm/360288464705?ss ... 1423.l2648

What do you think about this one?

[Torch]

What do you think about this one?

How'd they get an endmill mounted between two centres like that?

[stevec]

Torch, I've got a few four or mor flute endmills that would mount like that but my question is, how to you controle their orientation/rotation??

[Torch]

Torch, I've got a few four or mor flute endmills that would mount like that

The number of things I don't know about this hobby never ceases to amaze me.

In one or two of the photos there is an accessory that looks like some kind of finger. Maybe the flute rides along that and rotates on the centres as the table traverses? Of course, that would only work if grinding towards the edge.

[dly31]

Torch, I've got a few four or mor flute endmills that would mount like that

The number of things I don't know about this hobby never ceases to amaze me.

In one or two of the photos there is an accessory that looks like some kind of finger. Maybe the flute rides along that and rotates on the centres as the table traverses? Of course, that would only work if grinding towards the edge.

Many of the cutter grinding instructions I have read show the use of the indexing guide finger to control the rotation of the cutter. I have also read that grinding against the cutting edge is done by manually holding the cutter against the guide finger.

[wsippola]

I have no knowledge on the quality of the chinese cutter grinders, but the one on ebay is pretty substantial at almost 500lbs.

I built one using a Gorton 375? tool holder, which saved a LOT of work. The Hanita site used to have a nice paper on grinding endmills with eccentric relief, and the process works pretty well. It basically sets the wheel at a small angle from perpendicular to the tool travel, which along with the helix of the tool, causes the eccentric relief of the radial edge.

I suppose one could come up with ways to grind endmills on a surface grinder, however it's not really set up the right way. The wheel orientation is wrong with respect to the X axis. This would create interference with the tool holder. If the tool was set perpendicular to the wheel, you would have to do a lot of cranking on the crossfeed to grind each pass.

I have very limitted experience grinding cutters, but yes, the finger sets the geometry of the cut. You rotate the tool holder by hand, keeping light pressure of the endmill helix against the finger, as the table is stroked over. I've posted the photo before, but here's my home built cutter grinder.


Wayne

[oscer]

So, I nixed the idea of buying a Chi-com cutter grinder and bought an old Gorton model 375 it is missing a few parts which I'll probably have to make but they look to be well built, I guess time will tell. If anyone knows of a sorce for parts/ accessories I'd be interested. Thanks oscer