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Black Forest
05-12-2010, 07:20 AM
I saw this machine at a trade show not long ago. The man demonstrating it would blue the edge or cutting edge of a drill bit or end mill and then hold it under the rotating wheel and sharpen the tool. The rotating wheel is diamond inpregnated and has holes in it so you can see through to the edge that you are sharpening. It was interesting to see the blue taken off. I tried it myself and thought it would be a good addition to my shop.

I can sharpen my drill bits by hand on a pedestal grinder but not as good as I would like. I was curious if any of you have seen or used something like this.

http://i853.photobucket.com/albums/ab91/burnandreturn/SM180-1.jpg

Black_Moons
05-12-2010, 07:22 AM
Nifty, But should'nt that be a CBN wheel for HSS use? :)
'Silly rabbit, Diamonds are for carbide.'

SGW
05-12-2010, 08:12 AM
It costs a thousand bucks (on sale for $899), which puts it out of my league.....

Toolguy
05-12-2010, 08:44 AM
Diamond works just fine for HSS too.

Lew Hartswick
05-12-2010, 09:55 AM
Watched one of those being used by a wood carver quite a few years
ago. Workrd good for chisels and carving tools but for lathe bits etc
I think the Glendo machine is FAR better bet.
...Lew...

Ken_Shea
05-12-2010, 10:49 AM
It costs a thousand bucks (on sale for $899), which puts it out of my league.....

Always wondered where they come up with prices, flip a coin?
guess? maybe a dart board?.

No dang wonder it's on sale for $900, no, I'm sorry, $899, still over priced by a factor of two or three. These places need to think on perhaps making a nickel three times is better then making a dime once.

Duffy
05-12-2010, 11:29 AM
So company at the local Wood Show was demonstrating a similar, but MUCH more crude arrangement. It was a clamp that held an electric hand drill vertically near the edge of the bench. A diamond wheel, with holes, mounted on a mandrel, was chucked in the drill. The drill was sharpened on the underside of the wheel while control and progress was watched through the holes. The guy demonstrating it was VERY good, but you can bet that it takes a lot of practice to really get the hang of it. This "kit" sold for about Cdn $90.00, and no, they would NOT sell the wheel separately. Duffy

krutch
05-12-2010, 04:10 PM
A motor, standoff. eyeglass, and holy wheel. Priceless! Someone will copy this in their HS. And not for $900.00! Now, just where do ya find that wheel?

Black Forest
05-12-2010, 04:15 PM
They will sell just the diamond disk. A small one for a angle grinder or drill is 50 Euro's. The larger one is 199 Euro's. The light/magnifier is 125 Euro's.

JoeFin
05-12-2010, 04:21 PM
at $900 is certainly isn't tempting me the slightest

and if that is an AC motor what is going to absorb the woo/flutter

form_change
05-12-2010, 04:46 PM
The bluing that you see is an oxide layer. Removing the blue colour with a grinder is easy, but the real question is what has happened to the underlying temper of the material? That can be damaged but in the absence of oxygen won't go blue.

Michael

MuellerNick
05-12-2010, 05:07 PM
They are selling the disk alone here in Germany since years (Kaindl is a German company).
This motor with magnifier seems to be quite new, haven't seen it yet.

I don't have one. I know some who have such a disk and they are quite happy it seems. At least, I haven't read some negative feedback.

I won't buy one, somehow I don't see the big advantage. But maybe I'm just too old to change habbits.

Here (http://www.kaindl.de/shop/diamant-sichtschleifscheibe-p-38.html) are the prices and a video.


Nick

Duffy
05-12-2010, 06:20 PM
The "bluing" is drawn on with a felt tip pen to act as a guide as you grind. I watched the demonstrator do it-covered the bevel angle of a dull chisel, then proceded to adjust his holding position until the blue ground away.

Your Old Dog
05-12-2010, 07:39 PM
So what is it they are doing? Do they strobe a light on the work to be sharpened that coincides with the speed of the wheel hence the speed of the viewing holes?

The Artful Bodger
05-12-2010, 08:49 PM
So what is it they are doing? Do they strobe a light on the work to be sharpened that coincides with the speed of the wheel hence the speed of the viewing holes?
A flourescent tube around the viewing lens would strobe the wheel at 50 or 60Hz.

Mike Burdick
05-12-2010, 09:34 PM
Black Forest,

What RPM is the grinder? For fine grinding with a diamond, a slow speed is desirable. One thing I like about a flat circular grinding wheel like they're using is that it does provide a "variable" speed range since one can choose the speed by the location one does the grinding on the disk. I have a diamond wheel submerged in water on what is basically a potters wheel and it does a great job on HSS and carbide...and NO dust gets put in the air!

.

kendall
05-12-2010, 09:40 PM
So what is it they are doing? Do they strobe a light on the work to be sharpened that coincides with the speed of the wheel hence the speed of the viewing holes?

Just holes spaced so the disk becomes 'transparent' when in use, the same way fan blades do.

A strobe on a non-black wheel would tend to glare and make it harder to see through.

ken

lazlo
05-12-2010, 10:45 PM
Maybe I'm missing something obvious, but I don't get it. Sure, you can see the edge as you're grinding it -- how does that help?

For a woodworker you can free-hand the angles, but with metalworking bits you usually use an angle guide/tilting platen...

oldtiffie
05-12-2010, 10:48 PM
Originally Posted by Your Old Dog
So what is it they are doing? Do they strobe a light on the work to be sharpened that coincides with the speed of the wheel hence the speed of the viewing holes?

Just holes spaced so the disk becomes 'transparent' when in use, the same way fan blades do.

A strobe on a non-black wheel would tend to glare and make it harder to see through.

ken

You've got it right Ken.

I have some re-inforced 4 1/2" and 5" angle grinder discs from my local BOC sales depot. Those wheels have "bites" or "scallops" out of the periphery. They are dearer than the plain disc version but they cut faster, better and cooler and you can see right onto where the wheel is grinding. There is no "stroboscopic effect" needed as it is all visible in all lights - sunshine, fluorescent and incandescent.

RancherBill
05-12-2010, 11:07 PM
Here's the video for the grinder

http://www.youtube.com/watch?v=Gl1tjo2B-rU

Ian B
05-13-2010, 05:41 AM
The first thing that strikes me is that there's no toolrest - the piece that you're grinding is only steadied by your hands, which doesn't seem like such a good idea.

They say that you "automatically" grind tools at the right angle. Er - if you grind a tool by removing a layer of ink from a marker pen, the best you can do is to repeat the previous angle. If that angle was wrong, or it had drifted over several sharpenings, then you'd just be copying wrong angles.

Clever concept, drop the price by a factor of 10 and they may sell some to the Drill Doctor market sector.

Ian

Your Old Dog
05-13-2010, 07:32 AM
Here's the video for the grinder

http://www.youtube.com/watch?v=Gl1tjo2B-rU

After seeing the thing in use I can see how it is a real tool and not just a gimmick. Maybe a machinist might only see one aspect but woodworkers and turning guys will know the value when working on hand chisels of all profiles. I wouldn't mind owning one but the price does seem pretty stiff.

Black Forest
05-13-2010, 07:56 AM
The motor turns at 1400 rpm. The man from the company told me the diamond wheels work better at slower rpm's and that is why they work good in a drill.