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Seastar
07-04-2007, 03:44 PM
I finally bought a tool grinder on sale from Harbor Freight. Paid $110 with coupon from flyer.
It looks good so far but I have this question - the manual (if you can call it that) says "NEVER USE THE SIDES OF A GRINDING WHEEL TO GRIND OBJECTS".
I thought that you were supposed to use the sides of cup wheels like those supplied with the HF grinder.
What do you think?
Is this a warning left over from some bench grinder or is it correct?
Bill

Joel
07-04-2007, 04:21 PM
Ignore the stupidity and grind away.

ptjw7uk
07-04-2007, 05:50 PM
If you use the side of the wheel, the wheel will be subjected to forces it was not designed to handle. I think you can use the side for just touching up tool bits and the like but no heavy grinding.
If you want to do heavy grinding always use the front face and the rest.
If you think about the purist grinding action in that it always is on the peripheral edge you can see why surface grinders and centreless grinders were invented.
So to be on the safe side dont use it!!
Peter

Bill Pace
07-04-2007, 06:15 PM
That type wheel is designed to use the side, however you will probably find out very quickly that the wheel that comes on the grinder is very poor quality and you should consider replacing it with one of a better quality.
The grinder itself has gotten overall quite favorable reviews,--- with a few exceptions, as with a lot of HF type tools its always a bit of a gamble.....

Joel
07-04-2007, 06:20 PM
Peter, as Bill said, this type of grinder is designed for grinding on the face of the wheel.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=46727

I definitely agree with changing out the wheels. Use A/O for HSS and diamond for carbide.

lane
07-04-2007, 06:21 PM
On a tool grinder the side of the wheel is the diameter. On a standard bench grinder the diameter is the face of the wheel and the side is the flat sides what is the side of the wheel changes depending on the type of wheel. On a cup wheel the side is the face and the round part is the side.

Mcgyver
07-04-2007, 06:57 PM
i'll muddle up the terminology even further - when you are grinding with a t&c cup wheel, in fact you are grinding on the OD, the round part not the flat end. the wheel is dressed, the angled and the work advance such that its the outside not the flat face that actually does the cutting with a degree or two clearance between the work and flat part of the cup wheel.

i'm not the old hand at t&c grinders so there's probably countless examples proving this statement wrong, but seems true based on work i've done and what i've read/seen.

Seastar
07-05-2007, 12:30 PM
Now I am really confused.
Some are saying grind on the Face (radius) and others are saying grind on the Side (flat part) of the cup wheel.
To make things worse the on line manual for the HF tool grinder shows tools being ground on the Side or flat part while the manual that came with the grinder shows tools being ground on the Face or radius.
Now I am not even sure what to call what.
Can anyone shed light that I can see???
I don't want a wheel to explode in my face.
Bill

motomoron
07-05-2007, 12:53 PM
I have that very Harbor Fright grinder, and very much recommend that the cast drive flanges to which the wheels are bolted are nothing like round, flat, concentric, or balance. fancy that.

I removed them, chucked them on an arbor in the lathe, and trued them, all over.

The grinder runs infinitely smoother now.

I also replaced the GREEN PAINTED white wheels with some Norton wheels I had around. I'm going to get a cheap diamond wheel from CDCO or Shars for one side eventually.

Oh, as for what face is the face upon which you're to grind, it's the flat one. And the round one.

Avoid forceful use of the flat side of a conventional bench grinder wheel, but don't be terrified of using it gently. wear a flip down lexan faceshield if you're squeemish. Or use your belt sander instead.

mayfieldtm
07-05-2007, 02:09 PM
These wheels have a metal back plate.
Grind on the surface just opposite of the back plate.
This is the "Face" and will give a flat grind.
The outside surface would be the side and I use it for only light grinds.
It gives a concave grind.

I agree... Purchase a Aluminum Oxide wheel and a Diamond wheel.

My supplied "green" wheels quickly turned to concrete color?

I mounted the whole unit in a Metal Tray and use a small water pump to circulate coolant.

Tom M.

Joel
07-05-2007, 02:21 PM
Yes, grind on the flat part of the wheel (the 'face'). The cup wheel is fully backed, so it is not really comparable to a standard grinding wheel supported only at the arbor hole.

Seastar
07-05-2007, 07:36 PM
That what I thought.
Thanks for all the input - the face it is.
Bill

darryl
07-05-2007, 09:36 PM
Just don't grind on the bottom- or the top. Or the edge. And never grind on the green part of the painted wheels. And never let the rpms drop below 3840, even when powa off. Or you will die. :)

Sorry, just making fun of fu'd instructions, nothing else.

Seastar
07-06-2007, 08:14 AM
Darryl-Gotcha LOL!
Bill

heavysteamer
07-06-2007, 09:33 AM
These wheels have a metal back plate.
Grind on the surface just opposite of the back plate.
This is the "Face" and will give a flat grind.
The outside surface would be the side and I use it for only light grinds.
It gives a concave grind.

I agree... Purchase a Aluminum Oxide wheel and a Diamond wheel.

My supplied "green" wheels quickly turned to concrete color?

I mounted the whole unit in a Metal Tray and use a small water pump to circulate coolant.

Tom M.

Exactly right. The "face" on this type of wheel is in a different place than it is on a regular grinding wheel.

Evan
07-06-2007, 10:16 AM
I would sure like one of those grinders. I have the wheels. :D

I haven't found anyone that sells that grinder in Canada and HF doesn't ship to Canada plus shipping would be exorbitant. We went over this maybe a year ago. Has anyone in Canada seen this grinder for sale here?

ammcoman2
07-06-2007, 10:24 AM
KBC has them for $486 Cdn (part # 2-008-001). Still less than a third of the price of a Baldor but expensive cf a HF unit. A few years ago I was at the Barrie, Ont. Auto flea market and a guy had one going for $100 - foolish me, I passed!

Geoff

Evan
07-06-2007, 09:52 PM
I know about the KBC unit but I'm not in the market at that price. I'll make one eventually if I can't find one cheap enough.

lane
07-06-2007, 10:35 PM
Evan just drive across the border to Washington or something and buy one and bring it home.

John Stevenson
07-07-2007, 06:38 AM
I know about the KBC unit but I'm not in the market at that price. I'll make one eventually if I can't find one cheap enough.

Make one.

http://homepage.ntlworld.com/stevenson.engineers/lsteve/files/face_grinder.jpg

No problem to a man of your skills and experience.
I used to make these years ago before cheap imports came into the country. Just a 3,000 rev fan motor with bolted on flange so they can go either way and a tilt table with grooves for a protractor fence.

This is the last one existing, all the rest have been sold or given away, even this one isn't used anymore and is in storage.

If you can't build one just play with your stocks on the computer, make another $16,000 in a morning and buy one. That way you can also get a bottle of gas for your welder and not have to wait for your next months pocket money.

.