Bench grinders

[precaud]

I need a better bench grinder - my old Craftsman unit bogs under the slightest load and vibrates more than grinds. My use is mostly for general tool sharpening, and some materials shaping.

I like the idea of larger, fatter wheels so I'm looking at 8 inch units. I've come down to these two:

Northern Tool - http://www.northerntool.com/shop/tools/product_17016_17016
Ryobi - http://www.cporyobi.com/factory-rec...7,default,pd.html?start=4&cgid=ryobi-grinders

Home Depot sells the Ryobi (in store only) for $65, the NT is currently on sale for $50 w/ free shipping.

NT plusses: more powerful motor, less costly. Minuses: non adjustable tool rests
Ryobi plusses: adjustable too rests. Minuses: less power, lots of plastic parts

Any input or other suggestions would be welcome.

 

[smokinj]

My vote Ryobi!

 

[EatenByLimestone]

If you are in the market it might be worth while to look at the different types available. For instance, 6"ers typically run 3500rpm, deburring wheels don't like to run that fast so I use a 1/2 hp appliance motor to run it. Slow speed grinding has it's benefits also. If you are going to get a new one, you might as well make sure it can do what you want to in the future.

Matt

 

[precaud]

Thanks Matt, I hadn't considered multi-speed units, and don't recall seeing any, either. I'd guess that feature adds appreciably to the price, yes?

I usually debur with a dremel, where it's easy to change speeds, bits, etc.

 

[Battenkiller]

Slow speed grinding has it's benefits also. If you are going to get a new one, you might as well make sure it can do what you want to in the future.

I'm not a fan of cheap, high-speed grinders. If for no other reason, I don't trust the cheap wheels that come with them. An 8" wheel spinning at 3450 RPM has a lot of speed along the perimeter, almost 90 MPH. A cheap wheel is much more likely to fragment apart than a good Norton wheel, a situation that can kill you quicker than a chainsaw kickback. I have a slow-speed (1725 RPM) 8" grinder that came with two white aluminum oxide wheels. These wheels cut rapidly and yet remain relatively cool cutting. Much less risk of bluing the tool steel and ruining it. Get a good diamond dresser and keep them clear of glaze and they will stay cutting well. No need for high-speed unless you are in a production situation.

When I worked at Woodcraft we sold hundreds of slow-speed and two-speed 8" grinders. The two-speed ones are the ones that always came back broken. I've had this one for several years now and it had sharpened my turning gouges thousands of times with plenty of life left on the wheels. It's no Baldor, but it suits my needs well.

http://www.woodcraft.com/Product/2080939/29437/8in-Slow-Speed-Grinder.aspx

My preference is for a belt grinder. I have a 1 1/2 HP Stephen Bader belt grinder that takes 2" x 72" sanding belts. There are a great many types of belts, from straight ahead aluminum oxide abrasives to Zirconia to ultra fine Mylar-backed belts to felt and leather polishing belts. Different drive wheels can alter the belt speed dramatically, and there are many rubber-backed contact wheels available, plus a steel platen attachment for flat grinding. These things are extremely versatile, but they are way up there in price. I live about 1/2 hour from the Bader plant in Valley Falls, NY, so I went over there and bought a reconditioned BII (older model), but it was still almost $600. Worth every penny to me, though. A new BIII costs about $1700.

 

[precaud]

Thanks Batten, I had forgotten about the increased perimeter speed with the larger wheel. That unit at Woodcraft looks pretty interesting, and might be the way to go.

 

[Dune]

Battenkiller makes some good points. I use a beltgrinder far more often than a bench grinder.

That aside, I would buy neither of the grinders you mentioned. For one thing, they are both junk, especialy either one of them. I have bought a 10" milwaukee grinder for $25 with wheels, guards and rests complete. I have bought 2 Black and Decker 10" grinders for $50, and $100. I bought a Rockwell Carbide Tool Grinder, 6" with a cast iron stand, complete for $100, And a rockwell 7" grinder for $30.

As for belt grinders, heavy duty, Metalworking, 4x36 Kalamazoo, $100, 6x48 Kalamzoo, $100, 4x54 Rockwell $50, two 6x48 rockwell, $30 and $50. Missed a 4" Bader for $200 by a minute.

These are all grinders which wil last for the rest of my life, which were old when I got them. The same will not be said about cheap chinese grinders.

Industrial tools are pennys on the dollar these days. There are far more sellers than buyers. Craigslist has been good.

 

[precaud]

Hmmm... I just remembered, I have one of these in the garage, brand new:
http://www.baldor.com/products/detail.asp?1=1&page=1&catalogonly=1&catalog=L1200&product=AC+Motors&family=General+Purpose|vw_ACMotors_GeneralPurpose

I wonder if that would be enough torque and worth modding into one...

 

[EatenByLimestone]

For less than 1/5 of a horsepower I would rip the motor out of my clothes washer and buy the wife a new one. That one would probably be at least 1/3hp, maybe 1/2hp. The motors are identical rpm and built to work. If you go to any appliance shop you can probably pick up a good one with ports to oil your bearings for $10.

If you were closer I'd give you one as when I see them on the side of the road I tend to bring them home with me. It's a bad habit, kinda like scrounging but it rusts.

Matt

 

[EatenByLimestone]

I just reread your post and saw that you already have the motor. I'd sell it and get a full setup. The only weakness I see in the woodcraft mentioned above is the tool rests look a bit flimsy.

http://www.woodcraft.com/Product/20...r-with-Toolless-Quick-Change-Model-GR450.aspx

Matt

 

[precaud]

I just reread your post and saw that you already have the motor. I'd sell it and get a full setup.

That makes good sense. I'll work on it.

 

[EatenByLimestone]

Battenkiller, is that a simple rheostat on an induction motor? If so, I'd be back at the appliance store looking for a motor.

Add a stepped pulley and you can control the speed on a double mandrel fairly easily and predictably.


Check out how a guy ran an apple grinder with an appliance motor. The stepped pulley allows him to control the speed.


http://www.sentex.net/~mwandel/press/final_test.jpg

Instead of an apple grinder, I'd run a double mandrel off it like this:

http://www.leevalley.com/us/wood/page.aspx?p=32960&cat=1,43072,45939


Matt

 

[krooser]

I vote for a Baldor... buy it once and you will own it for a lifetime.

 

[precaud]

At a certain point in one's life, this concept of "own it for a lifetime" begins to mean less and less... literally. ;-)

 

[precaud]

Industrial tools are pennys on the dollar these days. There are far more sellers than buyers.

Perhaps out in the post-industrial east that is true, but not here...

 

[Battenkiller]

Here's one that won't let you down:

http://cgi.ebay.com/DELTA-6-PEDASTA...pt=BI_Pipe_Threaders_Dies&hash=item1e5ffc065f

Let me know if you'll pass on this, I might make a stab at it if you don't want it.

 

[Battenkiller]

At a certain point in one's life, this concept of "own it for a lifetime" begins to mean less and less... literally. ;-)

My dad died last year at 88. If I follow in his footsteps I have another 30 years to go. OTOH a guy I know just died at 58. A tool he bought at 28 would have lasted him 30 years... a lifetime in his case.

Buy the best if you can afford it. It'll piss you off less in the long run.

 

[precaud]

Beefy looking unit. Cost $40 just to ship it here... you take it.

 

[Dune]

Beatiful machine. The cast iron base is great to have. Missing both tool rests though. Not too hard to make, just a little time consuming, but very necasary. The end convers can be cut from aluminum, make a cutout for the spindle nut.

 

[Dune]

Here are some to consider; http://albuquerque.craigslist.org/tls/2075961425.html

http://albuquerque.craigslist.org/tls/2061165680.html

http://albuquerque.craigslist.org/tls/2047406340.html

 

[precaud]

Dune, I've looked at those ads, they're all 60+ miles away. I asked for pics of the first two but got no reply. The last one is missing tool rests, otherwise interesting, though.

 

[Dune]

Yeah, plus even the new Delta machines are but a shadow of their former selves. I would want something older and heavier. The dayton, even though it looks junky could be a real bargin.

Would you be able to locate a used machinery dealer in your area? The auctions I used to go to at defunct factorys never drew many buyers for small tools/machinery. The dealers often ended up with pallets of stuff for dirt.

 

[precaud]

There's nothing here in Santa Fe, it's all down in Abq. I attend the monthly industrial auctions down there, don't remember seeing a grinder. Often times the heavy machinery remains in place and is not brought to the auction site, so that may be why I don't see them. I'll keep looking, there's no rush, I've gotten by with this horrible unit for a couple decades, another month or two won't kill me. But thanks, I have a better idea of what to look for now.

 

[EatenByLimestone]

The tool rests that come on grinders are generally junk anyway. I'd upgrade if you are serious about grinding accurately.

The only thing I've heard bad about Lee Valley's rest is it is a bit soft and can wear if you don't give it a little love and cleaning every once in a while. I'm betting those who had the issue were heavy users of their grinder.

http://www.leevalley.com/us/wood/page.aspx?p=32975&cat=1,43072,45938


Matt

 

[Battenkiller]

The only thing I've heard bad about Lee Valley's rest is it is a bit soft and can wear if you don't give it a little love and cleaning every once in a while. I'm betting those who had the issue were heavy users of their grinder.

Aluminum is pretty soft stuff, anodizing notwithstanding. I wish they'd make that in steel and I'd be all over it. Very clever design, and they do work well in spite of the soft metal.


I use the One-Way system because of it's woodturning tool grinding abilities. It can be set up under any bench grinder and really is quite versatile for many types of grinding.


http://www.oneway.ca/sharpening/grind_jig.htm