PDA

View Full Version : New Hermes CG4 cutter grinder



Bob Fisher
11-01-2011, 03:51 PM
Anyone know about this machine? Is it something that I can't live without?One for sale locally for $250. Should I go for it? Bob.

DR
11-01-2011, 05:46 PM
This type of grinder can be handy for doing the ends of milling cutters, drills, lathe tools, etc. It's hard to make a judgment on this particular machine without info on it. The general category of machine comes in many versions from 50 pounds to several thousand pounds.

I would ask whether it has a diamond wheel for carbide or a wheel for high speed steel. And are wheels readily available. Also, what about work holding, does it use proprietary collets or a standard size. Are square collets available for lathe tools.

gary hart
11-01-2011, 06:17 PM
Bob, believe this is a grinder for sharpening single lip cutters. D-bit type cutters. Not very adaptable for doing end mills or drill bits. Good for sharpening engraving slingle lip cutters. Have one similar if not the same as this one and the only thing have used it for is making or sharpening the small D-bit cutters used for engraving.

Mike of the North
11-01-2011, 08:14 PM
Here is a link to it, I saw it but it is out of my price range.
http://detroit.craigslist.org/okl/tls/2679511447.html

DR
11-01-2011, 09:22 PM
Bob, believe this is a grinder for sharpening single lip cutters. D-bit type cutters. Not very adaptable for doing end mills or drill bits. Good for sharpening engraving slingle lip cutters. Have one similar if not the same as this one and the only thing have used it for is making or sharpening the small D-bit cutters used for engraving.


Is there something about the work holder or machine size that prevents end mills and drills from being done on your machine?

Here's a link to a site where a PDF for the Deckel single lip grinder can be downloaded. The PDF shows how Deckels are capable of end mills, drills, etc, etc. Of course, I don't exspect the New Hermes to be in the same league quality-wise as the Deckel, but the concept is the same. I've lusted after a Deckel single lip grinder for years, I always hope the ones at auction will go for $500 or so, but no such luck, they usually go well into the thousands.

gary hart
11-01-2011, 11:42 PM
DR, believe the Deckel has a slide on the work head that the New Hermes doesn't.

rickyb
11-02-2011, 01:35 PM
Anyone know about this machine? Is it something that I can't live without?One for sale locally for $250. Should I go for it? Bob.
I have this model and yes it does have limited use. It is referred to as a single point grinder and was designed for making 1/8" engraving cutters. $250 is a good price. If it has collets and grind wheels, its a bargain. Collets are 2B and impossible to find. Grind wheels are not available either.

2B collets are an internal thread draw bar with an 1/8" through hole. So even with the collets you can only chuck small length parts. I made a full set of external thread collets from drill rod and can now hold any length round up to 1/2" dia.

Stones are equally as difficult. I found some stones at a local abrasives shop and had them modified to fit. Diamond cups are available but need a sleeve to get down to the 1/2" hub diameter. At least that part was easy.

I use the grinder for pointing scribes and for making boring bars. Its easy(but slow)to grind the flat on the rod to 1/2 dia and sharpen and relieve the cutting edge.

I have not been able to devise a modification to the machine to get the extra degree of freedom to sharpen end mills.

DR
11-02-2011, 05:23 PM
I have this model and yes it does have limited use. It is referred to as a single point grinder and was designed for making 1/8" engraving cutters. $250 is a good price. If it has collets and grind wheels, its a bargain. Collets are 2B and impossible to find. Grind wheels are not available either.

2B collets are an internal thread draw bar with an 1/8" through hole. So even with the collets you can only chuck small length parts. I made a full set of external thread collets from drill rod and can now hold any length round up to 1/2" dia.

Stones are equally as difficult. I found some stones at a local abrasives shop and had them modified to fit. Diamond cups are available but need a sleeve to get down to the 1/2" hub diameter. At least that part was easy.

I use the grinder for pointing scribes and for making boring bars. Its easy(but slow)to grind the flat on the rod to 1/2 dia and sharpen and relieve the cutting edge.

I have not been able to devise a modification to the machine to get the extra degree of freedom to sharpen end mills.


Not to belabor a point, but if you can do boring bars why can't you do the ends of milling cutters?

From what you've said about the collets and wheels I believe I'd pas on it as a general purpose grinder. The Deckels and Gortons and others I'm familiar with are very sought after because they are general purpose ( even though they're called single lip grinders).

rickyb
11-03-2011, 11:03 AM
Not to belabor a point, but if you can do boring bars why can't you do the ends of milling cutters?

From what you've said about the collets and wheels I believe I'd pas on it as a general purpose grinder. The Deckels and Gortons and others I'm familiar with are very sought after because they are general purpose ( even though they're called single lip grinders).

To sharpen an end mill you need to be able to 1. align the cutting edge to about 1/2 degree from the end mill axis, 2. introduce the rake/relief angle perpendicular to #1, 3. feed in the end mill for the cut and 4. index to the next cutting edge. The Hermes can do 1 and 3 and be easily modified to do #4. There is no possibility to introduce the rake/relief angle #3. That is the extra degree of freedom that I mentioned was needed.

For most of us it is much, much cheaper to buy new end mills that to buy a used Deckel at $1500+.

jreinke
12-08-2011, 07:29 AM
I have this model and yes it does have limited use. It is referred to as a single point grinder and was designed for making 1/8" engraving cutters. $250 is a good price. If it has collets and grind wheels, its a bargain. Collets are 2B and impossible to find. Grind wheels are not available either.

2B collets are an internal thread draw bar with an 1/8" through hole. So even with the collets you can only chuck small length parts. I made a full set of external thread collets from drill rod and can now hold any length round up to 1/2" dia.

Stones are equally as difficult. I found some stones at a local abrasives shop and had them modified to fit. Diamond cups are available but need a sleeve to get down to the 1/2" hub diameter. At least that part was easy.

I use the grinder for pointing scribes and for making boring bars. Its easy(but slow)to grind the flat on the rod to 1/2 dia and sharpen and relieve the cutting edge.

I have not been able to devise a modification to the machine to get the extra degree of freedom to sharpen end mills.

You can get the 2B collets for the CG-4/5 from Quality One Engravers for $65 which is less than half of what New Hermes sells them for. New Hermes also sells all 3 types of grinding wheels, Aluminum Oxide, Silicon Carbide and Diamond.

Mcgyver
12-08-2011, 10:39 AM
Not to belabor a point, but if you can do boring bars why can't you do the ends of milling cutters?
.

I'd counter with what good does that do? Its the sides of a milling cutter that does the cutting and needs sharpening... except for the odd plunging op.

A grinder like this would be limited value over a bench grinder unless you need to sharpen engraving cutters....if you thinking getting this and its hello sharp milling cutters, that is a real stretch. Keep looking for a real T&C grinder that has a sliding table and has centres, tooth rest, air bearing, etc

I don't get the prices on this or the Deckels....one school of thought is there is only one Deckel out there that is constantly being put back on the market as each successive user realizes its not a T&C Grinder and isn't much use. T&CG, at least in the normal use of the phase which is taken to mean universal tool and cutter grinder.

like the curious pushing to through a crowd to see whats up, i might buy one one day to see what all the fuss is about....but I have a couple of T&CG so there's no false hope that it'd do milling cutters

Rosco-P
12-08-2011, 08:11 PM
Is buying a machine which has limited flexibility to sharpen end mills (and only the ends, 'cause it can't do the flutes) a good buy? You can get HSS end mills re-sharpened, including the flutes for as little as 2.50-3.00. That's at least 100 endmills before you hit the break even point, not counting the ones that you'll ruin from lack of experience.

DR
12-08-2011, 10:27 PM
I'd counter with what good does that do? Its the sides of a milling cutter that does the cutting and needs sharpening... except for the odd plunging op.

A grinder like this would be limited value over a bench grinder unless you need to sharpen engraving cutters....if you thinking getting this and its hello sharp milling cutters, that is a real stretch. Keep looking for a real T&C grinder that has a sliding table and has centres, tooth rest, air bearing, etc

I don't get the prices on this or the Deckels....one school of thought is there is only one Deckel out there that is constantly being put back on the market as each successive user realizes its not a T&C Grinder and isn't much use. T&CG, at least in the normal use of the phase which is taken to mean universal tool and cutter grinder.

like the curious pushing to through a crowd to see whats up, i might buy one one day to see what all the fuss is about....but I have a couple of T&CG so there's no false hope that it'd do milling cutters


I think you're showing your ignorance of this general category of grinder.

The grinder in question here may not be of great value, another poster in the thread mentions some limitations of this model.

As to Deckels and Gortons, they bring the big money because they're useful in a machine shop that might never use an engraving cutter. Lets say you use a lot of end mills, use the single lip grinder to do the ends only. Do the flutes on the regular T&C grinder. I have a Covel T&C grinder with a Weldon air bearing fixture, that's one of the ultimate EM grinding fixtures with a price to match. The Weldon will do the end, but it takes forever to switch over from flutes to ends, that's why I ve been looking for a Deckel or equivalent for years, but I don't want to pay the $1500+ prices..

There's no end to the ends (pun intended) that can be done on a good one like a Deckel. Drills,step drills, counter sinks, counterbores, spade bits, reamers, end mills, lathe cutters, taps in a pinch. All can be done easily on the single lip grinder. I believe some will even do corner rounding on end mills.

Mcgyver
12-08-2011, 11:15 PM
like I said, some interest if you already have a T&CG or two.....delusional thinking its what you need to sharpen endmills, shell mills, slab mills, basically any milling cutter.

oldtiffie
12-09-2011, 03:09 AM
Almost any T&C grinder can make a good fist of grinding the ends and side flutes if you clamp a "Spindexer" to the table.

My "Spindexer" is quite smooth and accurate - especially when it is used as a sliding-turning quill. No need for an air quill.

Just put your Spindexer on your table and have a good look for or at the possibilities. Its even more versatile with an angle-plate (for "tilt").

The Spindexer is one of the most under-rated and under-used tools in the shop. But it will need 5C collets or ER-32 collets if you use or buy John Stevenson's 5C >ER-32 adaptor (available from Arc Eurotrade (UK).

The Hermes CG4 Cutter grinder is pretty limited really.

So let the dog see the rabbit:

http://www.hydroponicsonline.com/store/New-Hermes-CG4-cutter-grinder_280678147174.html

http://www.google.com.au/#hl=en&cp=26&gs_id=36&xhr=t&q=hermes++cg4+cutter+grinder&pf=p&sclient=psy-ab&rlz=1W1IRFC_enAU360&source=hp&pbx=1&oq=hermes++cg4+cutter+grinder&aq=f&aqi=&aql=&gs_sm=&gs_upl=&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=f9f69ab5d57f4c56&biw=1920&bih=813

John Stevenson
12-09-2011, 07:19 AM
The single lip cutter grinders like the Deckel and Alexandra and clones have a serious design error* when used with end mills.

Very hard to describe so if I get chance tonight I'll take some pics and post them in a new thread. Once you see the setup in pictures it all falls into place.

*[Edit] Not really a design error as they were designed for single lip cutters not milling cutters.
The error if there is one is from the resellers who insist on calling these machines UNIVERSAL cutter Grinders.

rickyb
12-11-2011, 08:18 PM
You can get the 2B collets for the CG-4/5 from Quality One Engravers for $65 which is less than half of what New Hermes sells them for. New Hermes also sells all 3 types of grinding wheels, Aluminum Oxide, Silicon Carbide and Diamond.
Thanks for the info. I checked out the sight. Its nice to know they are available. As I had said in a previous post I made my own collets without the length limitation of the 2b size using an OD closer I had also made. The Diamond wheel I bought from a local abrasives shop for $65 has about 1/2 face width of the Quality One replacement($330) but I have yet to notice any disadvantage to it.

Again, thanks for the heads up.