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lynnl
02-28-2003, 03:35 PM
Currently my bench grinder (6") has a green wheel (med. grit) on one end, and a tan Norton fine wheel on t'other end. The tan one (no meaningful numbers that I've seen before) has worn down quickly. Also a few days ago the tool rest slipped, engaged the tan wheel, and brought everything to a quick halt. Both wheels had required bushing with nested plastic bushings to fit the .5" arbor of this grinder, so both were thrown out of 'true' ...by a lot. They still 'ring' good, but I want to replace that tan wheel anyway.
I'm looking for recommendations for a good general purpose wheel for HSS tool bits, gen'l purpose grinding, and yes, some twist drill grinding practice ...and more practice. http://bbs.homeshopmachinist.net//smile.gif
I'm too lazy to spend a lot of time changing wheels for specific tasks, so I'm looking for the best 'one size fits all' choice.
An MSC sale catalog just received has 6" diamond wheels for $79. Would that be a good choice? What about their longevity? Are they usually impregnated on both rim and side?

Also, should I turn me some bushings of Al or steel to replace those plastic bushings?

Tony
03-01-2003, 02:15 PM
Can't help you with a wheel selection but
i'd just say keep the plastic bushings if they fit the new wheels. if they've taken some damage turns some new ones out of plastic.

the bushings serve no purpose other than centering your wheel while you tighten the nut/washer on both ends. techincally, once centered/tightened, you could take them out.

thats a trick i'd like to see.

but unless you're looking to kill some time,
turn them out of plastic to make quick work of it.

i'd say soft plastic, turned slightly oversized to get the best "push" fit you can.

-knucklehead.

dkinzer
03-01-2003, 06:35 PM
I asked the same question on another board and got the advice:

"White aluminum oxide wheel with a "J" hardness. Run at 3450 rpm and dress to a nice even edge."

I haven't tried this yet. YMMV

Herb W
03-04-2003, 02:26 PM
As I understand it, diamond wheels on a bench grinder are good for carbide only.
If you grind steel, with the heat of grinding, there's some sort of reaction between the diamond & the carbon in the steel which damages the diamond.

docsteve66
03-04-2003, 06:12 PM
I recently purchased a grinder. Consult Machinnery's hand book for grinding speeds. At 3600 rpm, 8 inch grinders are just too fast for me. 6" is marginally ok. 1800 rpms are hard to find at reasonable prices. Speed does make a difference
Steve

lynnl
03-05-2003, 11:58 AM
An additional question: What'd be the results if I replaced the 3/4" wide wheels (or maybe just one) with 1" wide? I can imagine the grinder (1/3hp) being slower to reach top rpm. Also maybe a tendency to stall with a heavy grind load (ie. 33 % more area being ground). I'd have to make a slight mod to the wheel end-cover to insure no interference. Reason I ask is my local supplier has a Norton 32A wheel I like, but only in 1"W, not 3/4".

wierdscience
03-05-2003, 11:18 PM
Some of the local knife makers and wood workers have had me build grinding stations with multiple wheels on the same arbor,what I used for a shaft is a used or new horiz.mill arbor mounted on pillow blocks and belt driven I use the 1.250"arbor size as to make use of surface grinding wheels as I believe that they are made better than common bench wheels, they are also cheap on Ebay.I also recommend the white aluminum ox wheels for HSS grinding.The advantage of the mill arbor setup is that you can depending on the length of the arbor mount as many as six or seven wheels of different types and sizes as well as profiles on the same shaft.

Thrud
03-06-2003, 01:55 AM
Lynn
www.leevalley.com (http://www.leevalley.com) will set you up with a proper wheel for grinding your tools. They sell the Norton white wheels which are fine for HSS, but if you want a better wheel get a Norton SG series wheel (more money) or a CBN wheel which is great for hardened steel. Forget the Diamond, if you want a super abrasive wheel go with the CBN - but do not under any circumstance grind soft steel with it as it will wear prematurely. The last longest with the hardest steels.

docsteve66
03-06-2003, 12:31 PM
Lee Valley? I have dealt with Lee Valley off and on for 15/20 yyears. Visit their VanCouver store when I get that far west. Any one who does not ssubscribe to their catalogs is missing much useful information. They have several catalogs, are are very good. The quality of the stuff my wife buys from them is pleasing. I bet they have spent more on sending me catalogs tthan they have made in money, wife is differnet story.

The tips they give are usualy very good. check out the web site and order a catalog. I have no interest in Lee Valley other than as a customer bbut they are -to me- a fine exampleof how a business should operate.
Steve

Thrud
03-07-2003, 01:47 AM
Steve
Yeah, I don't either. But have been buying from them for years. They always stand behind your purchase. As they have a store here in Edmonton I can check out the "returns" which are offered at lower prices. People will buy a bit, use it, then return it for a refund. Mendicants. I bought a 2" Sorby framing chisel for $50 CDN - the bone head had used it, let it get slight surface rust and then broke the ash handle (how? - for a fresh one $10 CDN). WHAT A DEAL!

Frank McLean (RIP) did lots of early tool design for them - one of the reasons they only carry his book.

Koloya
12-17-2004, 08:42 PM
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[This message has been edited by Koloya (edited 12-18-2004).]