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I've been debating the purchase of a bench grinder for some time now. The one thing that stops me is, I feel that I can already do most things it will help do. Maybe there's benefits I don't know about yet? Thing is.... they seem so convenient. I was watching Frank Klausz sharpen chisels with his grinder on one of his videos. But then he followed that up with some Japanese stones, sandpaper, etc..... I also know that it's real easy to ruin your steel if you misuse them and usually the first thing you have to do is replace one wheel with a Norton 38A80 (or similar) if the grinder doesn't already come with one.

There are some quality units out there that are priced attractively. I want to hear from the grinder owners and see if there are any other virtues to them that I may not have taken into consideration yet. How often do you use yours? What do you use it for mostly? How important is it in your shop?
-John

I use my bench grinder a lot for sharpening drill bits, takes some time to get the hang of it though.

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Frank

I use mine alot.I sharpen screwdrivers,take burrs off of any steel i cut .It also has a buffer on the other end for polishing.

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Indispensible, IMO.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Thanks for all of the input so far guys. Howard, you said you consider your grinder, "indispensable". What role does it play in your workshop?
-John

Must have if you ask me. With an assortment of wheels for different profiles and purposes.
I've got a koolmist rig on mine to protect the temper.
-C

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Freeborn Guitars
and home of BeauGuard©

One way to help keep from burning the steel is to get a low speed grinder- 1725 rpm or lower,
instead of the standard 3450 rpm. Woodcraft and several others have them for pretty good
prices. Also get the right wheels- Aluminum oxide (white wheel) grinds a lot cooler.

Besides grinding, I use my wire wheels a lot to keep tools polished up and for minor deburring.

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

Fine grit wheel on one side for general purpose applications and sharpening drill bits and a hard white felt wheel on the other dressed with rouge for redressing the edge on chisels and plane irons. It really works well and gets them scary sharp again with just a quick pass. I use my grinder quite often and find it to be a necessary tool in the shop.

Regards,

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Peter

A bench grinder is the cheapest tool you will buy and it has a million uses. I particulary like it for sharpening pencils.

Seriously, small footprint, multi-use. I cannot explain it, but hardly a day goes by that I do not turn it on at least once.

Mike

Sharpen drill bits on a bench grinder... by hand? Yeah, I did that for years, and I mean like 20 years...and then I got a drill doctor and quit beating my head against a cement wall. Man did that feel good when I stopped doing it!
-C

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Freeborn Guitars
and home of BeauGuard©

If you have one, you'll find uses for it. If not, you don't need it.

I don't have one and I'd have no space for one (my bench space is very limited). I use one of two sanders (which I use for many other things) to grind my cutting blades on.

Drill doctor for me too Chas.

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My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

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That's kinda dangerous, since you grind toward the edge and hone with a felt wheel away from the edge. If you forget to hold your tool with the tip down when honing, it will grab and throw it, and without removing the tool rest there isn't much room to point the tool down. I use a second grinder (they are pretty cheap) turned around for honing with felt or MDF wheels. That way the tool always points the same way and I can keep the tool rests on.

As to the original question, I use the grinding wheels for grinding tool edges, as well as cleaning up rough ends on truss rods, and any other appropriate removal of metal. Then I have one set up for honing with felt or MDF wheels.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Woodcraft is preferred in the handtool world, putting Tormek aside. The grinder goes on sale for around $80-- biggest plus, aside from slower speed is that it comes with good quality wheels, of the type that helps with avoiding burning. It may seem counter-intuitive, but the coarse white, pink or blue(Norton, or of Norton type) avoid burning. Less contact time to achieve the desired result. Of course, you will need abrasive stones to finish out.mt

Funny, I have a setup similar to Howards. I have an old 6" grinder that I turned around and use with some of those cardboard sharpening wheels. One wheel has a 400 grit surface and the other wheel is used with white rouge for honing. I do plane edges on a diamond stone or sandpaper/glass. Works for me.

I also have an 8" slow-speed bench grinder from woodcraft that I like.

I find both to be indispensible.

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Steve Smith
"Music is what feelings sound like"

Howard, that's a great idea I'd never thought of. I have a few grinders that run on 3 phase, so I have the luxury of easily reversing them. I should switch one of those over and set it up dedicated to chisels. Are these MDF wheels you speak of, Medium Density Fiberboard? I've used hard felt, but never seen this. Do you use a compound with them?

As to grinders in general, I couldn't be without one. I have one small one that's stored away, and two bigger 3 phase ones on pedestals in the tool room. I turn them on at least several times a week, as there always seems to be metal to grind. A good disc sander dedicated to metal is nice to have as well.

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Eschew obfuscation, espouse elucidation.

MDF is very similar to those pressed brown paper wheels that are sold as a set for sharpening and honing (one with a grit bonded to its edge, and one with a bare slotted edge for honing). The slotting is to make it hold more compound, I think, and maybe dissipate heat. But you can make wheels of solid MDF that will hone very nicely. Helps to have a lathe to turn them round, but you could do it on a drill press or right on the grinder once you have them close. I use them with green chromium oxide compound (from Lee Valley), which I also use on a hard felt wheel.

Tip re the hard felt wheels: I harden them more by sizing the rim with thin shellac. Less likely to round the tool edge over.

Another thing about grinders: they tend to vibrate a lot if the wheels are not perfectly centered and balanced, which causes loss of accuracy (and makes things walk off the table ). I use saw stabilizers in place of the cheap stamped washers alongside the wheels, and fudge the wheels around until I've minimized side play. Then true the wheels, which may be running a bit out of round. Then mount to a bench made from heavy timber; 4-by is better than 2-by; then put a few sandbags on a shelf under the bench for more mass and damping. Once they are tuned up, they are like, how did I live without this?

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I use heavy tool steel scrapers that are sharpened on the bench grinder. You lap off the faces to get rid of the old burr and run the edge around on the grind wheel, with the tool rest set to give a precise right angle edge. The steel is hardened and just barely annealed for stress relief, and the burr from grinding is the cutting edge. If you've ever seen a old time carpenter scraping with a piece of broken glass, these are the same idea but with a a controlabler shape, and you can sharpen them. They are simply indispensible for making arch top instruments, and far superior in most uses to the usual card scraper, IMO. The edge lasts a long time, but would be hard to keep up without a bench grinder.

I just recieved a email from Woodcraft and they have a 8" slow speed grinder on sale for $79.99 with free shipping through Nov. if your interested. I've been wanting a bench for awhile so this might be it for me.
http://www.woodcraft.com/product.aspx?P ... e=08IN11NL

Well, these are not a substitute for a well sharpened card scraper if you want to leave a smooth surface. The kind of scraper Alan describes is like a heavy woodturners' scraper--it's a tool that can remove a lot of wood with a big rough burr that lasts. Turners rarely do any honing; the grinder is the sharpening system, and it's right from the grinder to the work, for gouges as well as scrapers. For woodturning, I grind scrapers a little more acute than 90º. A coarse wheel will raise a more aggressive burr, which is often what you want. But if you are using a scraper to get a fine finish that needs little or no sanding, that's a different tool, and a different sharpening method.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

A man just has to have a bench grinder in his garage. Get one if you can, you'll love it.

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

howard Klepper wrote:
"Well, these are not a substitute for a well sharpened card scraper if you want to leave a smooth surface. The kind of scraper Alan describes is like a heavy woodturners' scraper--"

Obviously you've never tried one of these, Howard. In fact, when properly sharpened I use this for the final smoothing of violin tops and backs before varnishing; no sandpaper. You can remove a lot of material with one of these if you have to, but you can also take the sort of light cut that can only be done with a really sharp tool. I've practically given up on card scrapers, and once my students try these, they're hooked.