Making Lathe Bits Without the "Right" Tools

A roasting spit for slow turning wild boars over coals. Trough a pulley system.

cheers T.Alan

Overhead crane, conveyor, mixer, elevator.

I haven't used an angle grinder to shape HSS cutting tools, but it seems like an appropriate method. Consider putting the cutting tool in a bench vise as Jim suggested, or make a bracket/framework to hold the angle grinder so it can be securely mounted in a vise or attached to something stationary, like a bench. Trying to use a 4-1/2" angle grinder wheel on a 3000 RPM bench grinder won't work very well at all, but getting a larger diameter wheel intended for bigger angle grinders may produce satisfactory/better results, although you'll need to make an accurate and safe adapter to mount a larger wheel to the bench grinder arbor/shaft. I wouldn't expect excellent results from this, because coarse grinding disks/wheels for angle grinders shed a lot of abrasive.. that's how they are able to keep cutting at a fairly consistent rate.

There are some tool sellers that sell 8 piece pre-ground HSS cutting tool sets for about $40 (or more for 3/8" size). I haven't bought them, because I assume that they're made from low grade Chinese HSS. Decide if buying a set of these cutting tools is better than dressing your grinding wheel. If you're redressing your grinding wheels with a diamond you'll probably waste a lot of abrasive.. get a good dressing stick instead (not expensive, maybe $8 or less) .

You might try gouging/hogging away the majority of the HSS with the angle grinder, then changing over to a bigger rotary tool like a die grinder with a 1/4" shank capacity/collet to do the finish shaping. Appropriate safety equipment is definitely required when using guarded or unguarded high speed power tools. The trouble with small Dremel-type tools is that they lack real power, and that nearly all of the 1/8" mounted stones are fine abrasive. I think the small rotary tools are great for light duty work, but shaping HSS tools is a demanding task.

As others have suggested, better quality grinding wheels provide better performance.

I manage to do all of the HSS rough and shaping with a coarse wheel on a bench grinder without too much trouble because I can grind HSS very aggressively using some tool holders I made.

If you don't grind aggressively, you might just be glazing the wheel, which makes it dull, and then it's just generating a lot of heat and very little grinding is taking place. You can actually see the face of the wheel is shiny if you point a light at it.. you can see the light reflecting from the wheel surface. The glaze can be broken down quickly with a dressing stick, after which you'll notice a dramatic difference/improvement in the effectiveness of the abrasive.

I believe Harold has made all of the required recommendations for selecting and using grinding wheels effectively for grinding HSS cutting tools. You can download the PDF here:

I also haven't used belt sanders/grinders for shaping HSS, but many lathe owners say they're great. Just be aware that they can create crowned facets (beause the belt can start to rise and be a bit loose where it meets the workpiece), so don't assume that all surfaces will be flat.

Thanks, George. Very informative on all. I can recommend the protractor table from

4 X 36 belt sander with 6 inch disk. Use zarconia [blue] belts to rough grind and a fine grade disk to finish grind. With a fine grit on the disk you can get a literal mirror finish. example of sander of zarconia belts [scroll to bottom of page] of disks car parts places that have painting supplies will have even finer ones down to 2000 grit for a super finish.

The protractor on the fence/table is OK for wood working, but an improved holder and accurate guide will give you better and more repeatable results. for my solution see

Also get one of the machining textbooks that discusses lathe tool geometry and nomenclature. Moltrecht vol one is good. [get both volumes when you order.] Frequently on sale from Enco and Amazon the reprints from Lindsay books are very good and are priced very reasonably. any of these lathe books will be very helpful. Just make the tools look like the pictures to start. angles have been developed over 100 years are more. After you get this down, you can vary to see what works best with your machine and way of working. Be sure to keep a notebook and sketch what you do for easy reference.

A tip -- regular M2 is both easier to grind and cheaper than 5 or

10% cobalt, and will be more than adequate for your initial projects. Also for the typical hobby/home shop lathe, rake at the high side of the recommended range, or even above can be helpful as this reduces the cutting forces. The trade-off is shorter tool life, but this is not a major consideration for home/hobby shop use.

Unka' George [George McDuffee]

------------------------------------------- He that will not apply new remedies, must expect new evils: for Time is the greatest innovator: and if Time, of course, alter things to the worse, and wisdom and counsel shall not alter them to the better, what shall be the end?

Francis Bacon (1561-1626), English philosopher, essayist, statesman. Essays, "Of Innovations" (1597-1625).

I'll attach it to an email. watch your inbox for a large file ;)

Also too big, and it's non-reversible. This thing is the size of a 3/4HP motor, plus the gear drive housing. The case is about 6" diameter

Hmmmm. I do need something to lift heavy bulky objects up to 8 feet. Might be something there, but the motor is not reversible. At least it doesn't appear so.

Paint mixer might be doable, and I often need one.

I have a Thern winch that is made for lifting heavy objects.

110v, 1 1/3 HP power, works great.

Price is $300.

This is the most versatile cheap hoist I've seen.

I bought the 2 ton one, in a store rather than from HF, because it's the heaviest I can lift overhead and maneuver onto the hanger loop with one hand. The harder part is getting it off the hanger which means holding it by its hook to open the safety catch with one finger. My other hand is on the ladder so the heavy swinging chain doesn't pull me off balance.

It will pull a stuck vehicle if you have a helper to feed the hauling chain in horizontally. Otherwise it jams. I store it in a bucket that I put under it in use to keep the hauling chain out of the dirt.

Lever chain hoists are faster and easier but you need to be where the lever is. The chain fall lets you stay on the ground farther away from the load. I haven't tried non-commercial electric hoists since I rarely lift heavy loads close to an electric outlet.

Jim Wilkins

I have a very similar one (probably made at the same factory), and it works beautifully, but it is slow.

Lever chain hoists are best for pulling, that's how I use one.

Now... A question... Is there any advantage to a "cable puller" over a lever chain hoist, for pulling stuff? 4 ton puller in my instance. Got one in auction yesterday and cannot decide if I should keep one.

Before I found a lever chain hoist at a good price I used the cable ones to lift firewood logs since my back won't tolerate leaning over all day.

The import cable pullers wear VERY quickly unless you disassemble and grease them first. Usually the ratchet and lowering mechanisms need some BFH adjustment too. After this I could get a year or two out of one before it deteriorated and jammed. The Jet lever hoist has gone 10 years with no problems.

The "4 ton" cable puller I have requires perhaps 200 Lbs on the handle for 3200 measured Lbs of pull in the two-line configuration with about half the cable wound on the reel. Leverage decreases rapidly as the reel fills.

A neighbor's large oak had fallen into a crotch on another tree during a storm. It was a straight log I wanted to save for lumber, this one:

trunk up a steep hill. I had been cranking away at it for a while, two or three clicks per pull, and stopped to rest. The ex-Marine, construction worker neighbor stepped in to show me how it should be done and couldn't move it even one click, probably because he's leaner and doesn't have the momentum or bicycling leg muscles.

Finally I worked my tractor into place above it and pulled it free with the 2500 Lb winch and a snatch block. There is enough slack in the electrical cable to chain the winch to a tree beside the tractor.

Bottom line, the cable pullers are like $20 angle grinders, OK as long as you don't need them often or depend on them. When I pull a large leaning tree to fell it in the opposite direction I need several pullers because one doesn't pull far enough.

These help a lot by taking up the slack:

have the yellow ones from WalMart instead. Pull on the free end of the strap to take up as much slack as possible, then crank the ratchet handle a few times. Otherwise about a quarter of the cable pull is wasted, and the cable doesn't wind smoothly without a load.

Jim Wilkins

Jim, you have a fun life and great photographic skills. It appears, based on your experience, that I do not really need that puller for anything. I will just sell it. The 1.5 ton ratcheting chain hoist that I have (CM) works great every time at its designed parameters, and also allows me to release chain in a controlled fashion. I could always double its force if I wanted, as well.

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You should have posted this picture too, it is awesome:

Mounting the angle grinder cancels the advantage of holding the cool object instead of the hot one. I think a bench grinder would be better.

I've messed around with several versions of a thin wheel to grind recesses and still like the hand-held angle grinder best. For one thing it keeps the sparks and shed abrasives on the far side away from your face. A cut-off wheel in a table saw isn't too bad, but the one I set up is deliberately low-powered to limit potential violence. You won't catch me grinding on the chop saw with the switch tied down!!!

The coarse wheel on my pedestal grinder is about right for woodworking tools, but not aggressive enough to rough a lathe bit blank quickly. It's fine once the bit is close to size, that's why I shape them first with the angle grinder. I simply don't have the space to have the correct grinding wheel for everything. The SiC fine wheel is a barely adequate compromise. I'd rather have a separate Baldor with one SiC and one diamond wheel. Does anyone in the Nashua area have one they don't need?

If the top roller isn't guarded you can hollow-grind bits on it without that problem since the belt is tight there. Otherwise sanding with the cutting edge down seems to help, although it may leave a wire edge.

Although it never happened when I was present, the belt on the sander at MITRE sometimes had holes ripped in it where the piece being sanded dug in. I think people were sharpening their lawnmower blades on it and a corner caught.

Jim Wilkins

I have one of those, and a smaller one. i use them a lot, but haven't used them for horizontal pulling.

I used a big cable comealong from HD to pull a 12x16 wooden building up a hill and a 90deg turn a few years ago. Worked like a charm one I worked out the right trees to hook it to for each segment.

I like the bandsaw and the front-end loader

Well, I'm a big supporter/believer in whatever method has been working for someone, is a good method for them to use.

I don't hold HSS blanks in my fingers anymore, since I made the holders mentioned in my earlier reply. Heat isn't an issue, so that permits me to essentially grind the hell outta blanks without turning my fingertips to leather.

I agree Jim, the chop saw usage would be foolish.

Using actual cutoff disks for HSS is a bit more difficult than using them with mild steel and sheetmetal. In contact with HSS, the operation slows down greatly as the actual process changes from cutting to grinding.

I've got some 6" 1/4" wide aluminum oxide wheels that I'll use when I get another bench grinder, but like you suggested, for lots of general shop grinding variations it takes several grinders with different abrasives "mounted and ready to go" when needed, which also requires more shop space (hopefully isolated from the shop machines).

I'm convinced that a specially-built grinding setup/fixture just for lathe cutting tools would be a worthwhile project, kinda like a compat version of a T & C grinder just for lathe cutting tools. That was the direction I was headed in when I made the holders for grinding blanks, but the idea was set aside as I got interested in other projects.

The grinding/sharpening machines that use a right-angle worm gear reducer to provide a fast dry wheel, and a slow wet wheel could be very versatile, maybe moreso for a woodworker though.

I do OK with grinding HSS cutting tools, but better vision would make it much easier (even though I use good lighting and a big magnifying lens at the grinder).

I've seen other examples of belt sander abuse by plant personnel that shouldn't be alllowed anywhere near such a machine. It seems that many folks find belt sanders less intimidating than a big grinder, and they try to do all sorts of foolish stuff with them, many times it's stuff that should be done with a file anyway.

I've been using my surface grinder to clean up woodworking blades that have drifted out of square. It works but it's definitely not the right tool for general resharpening because it burns the carbon steel too easily. I think I can take off up to 0.002" per pass without bluing the edge. The surface grinder does a very nice job when it removes a only few tenths, such as resharpening my jointer's cutting head between centers.

It's down right now. The spindle adapter doesn't match Sopko drawings, the taper is different, so I'm making some more and a dummy spindle that runs between lathe centers.

"Not the right tool" describes much of what I do at home anyway.

Jim Wilkins