# how do you properly hone a tool bit?



## mickri (Mar 26, 2019)

Give me a hone and a tool bit that needs final sharpening and I will make it duller faster than you can blink.   I am honing challenged.  I see lots of references to using a hone to put the finishing touches on a tool bit.  But I have yet to find anything on how you go about doing that.  In my feeble attempts all I seem to do is make the tool bit duller.   Help me out please.


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## b4autodark (Mar 26, 2019)

I could also use instruction on this. Thank you for bringing it up mickri.


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## Cadillac (Mar 26, 2019)

That's a tough one. You need to feel the flat of the surface wanting to be honed and if anything fall away from the edge to not roll it over. Sometimes I hold the stone in my hand and sometimes I hold the tool in my hand with the stone on the bench. Try to alternate directions so yo can read off the old scratches what adjustment you might need in your angle. Take a sharpie cover you tool then work up to the edge without taking the sharpie off leave that till the last strokes. Lots of light and magnifiers usually.


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## savarin (Mar 26, 2019)

I just use those diamond hones stuck to a bit of plastic like these





						DMT D2K 2.5-inch Dia-Sharp Diamond Mini-Hone Kit of C, F, E - Sharpening Stones - Amazon.com
					

DMT D2K 2.5-inch Dia-Sharp Diamond Mini-Hone Kit of C, F, E - Sharpening Stones - Amazon.com



					www.amazon.com
				



just a few strokes copying the angles the bit was ground at.
I keep the bit in the holder on the tool post whilst doing this so it doesnt move around.
Its easy to see the edge as it gets shinier.


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## benmychree (Mar 26, 2019)

I have seldom felt the need to hone a tool bit; if they are properly sharpened on a grinding wheel of fine grit after having been roughed out on a coarse wheel, they are sufficiently keen edged for most any job.  I save the diamond grit on a slab of plastic for sharpening knives, for that, they are wonderful!  For woodworking edge tools, I use a 3 stone set like the butchers use, finishing with an India stone, got hard Arkansas, but rarly use it.


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## mickri (Mar 26, 2019)

Do you stroke towards the edge or away from it.


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## f350ca (Mar 26, 2019)

For me time is cheep so I usually give my lathe tools a quick hone on a medium stone, but they probably don't need it. I wet the stone with kerosine to keep it clean. If you grind your tools on a grinding wheel the hollow shape left by the radius of the wheel makes honing quick. Hold the cutter so that the ground face is flat on the stone. A few swipes back and forth will show the honed edges at the top and bottom of the grind. Repeat on the other faces. Form tools such as threading tools that have a flat top just require  a rub with the face flat on the stone.

Greg


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## mikey (Mar 27, 2019)

I've been honing tools for a little while now so I'll give this a shot. The decision to hone or not is up to you. Many experienced machinists don't bother. I do it because the tool cuts easier, more accurately, finishes finer with fewer surface defects from an unground edge and they last longer. I don't usually regrind a tool beyond the initial grind. I hone them until my rake angles are no longer effective and I throw them in a bucket; this can take 10-15 years to occur. Until then, a honed tool cuts like new.

It is important to grind a good tool. This means your tool has a geometry that you feel will work for you and that the faces of the tool are not full of facets or grind marks. If you have these defects it will take you a long time to get rid of them so grind the tool well.

It is also important to understand that you are not honing to produce an edge. *You are honing the three faces of the tool so that they are dead flat, or at least the upper and lower edges are flat and co-planar to each other on a tool ground on a wheel*. The edges are precise intersections between these flats and by flattening each face, the edges take care of themselves. When all three faces are flat, the edges will be very sharp and will not reflect light. If you see light reflecting off an edge then that means one of the tool faces is not flat.

You can use water or oil or diamond stones to hone. Sand paper does not live long enough to be an effective medium for initial honing, although you can use it for touch ups. I usually prefer diamond stones for most sharpening/honing but for fine finishing tools or gravers, I go from my extra-fine diamond to a fine India stone and then to a Translucent Arkansas stone. This puts a mirror finish on the tool and it cuts like a razor. 

For honing lathe tools, I use a steel backed diamond stone. I prefer a 6-8" bench stone for initial honing and the credit card sized ones for honing between uses. A few seconds of attention to each flat before the tool is put away keeps my tools sharp and ready to go whenever I am. I stay away from plastic-backed diamond sharpeners for lathe tools; they flex under pressure.

I also use water with a bit of Dawn soap or a wetting agent in it to lubricate. This helps flush debris away and keeps the stone cutting well. 

Again, the goal is to produce a very flat surface on each face. I usually start with the side cutting face. My personal technique is to hold the stone in my left hand (I am right handed) and the tool in my right hand. I get the face flat in both the vertical and horizontal directions, lock my wrists and apply moderate pressure on the pull stroke only. A diamond stone cuts best under light to moderate pressure; high pressure only wears the stone and doesn't cut any faster. Let the stone cut. I hone over a container with water/wetting agent or soap in it and dip the stone after a few passes. The goal, again, is to flatten the face and I check it often to make sure I am doing exactly that. 

I start with a coarse diamond stone, then go to a fine stone, then an extra-fine stone. The goal is to produce a homogeneous surface across the entire face. Once you get that, move to the next grade and do it again, and again for each face.

Once I get the side flat, I move to the end and then the top. The process is the same - get the face you're honing set dead flat on the stone, make sure your wrists are locked (locked, not rigid) so your tool angles don't change and hone on the pull stroke with moderate pressure. I find that applying pressure on the push stroke works too but the tendency to roll the tool and grind down an edge happens too easily so I avoid doing that. 

For me, the hardest face is the end face. The surface area is very small and it is difficult to feel when the tool is flat on the stone. It helps to color the face with a Sharpie so you know when your wrist angles are right and then try to maintain it. It takes a bit of practice to do this so stick with it. 

Once I have all three faces dead flat, I create the nose radius with a extra-fine diamond stone and then take a final pass on the top face of the tool to eliminate any burrs that may have formed. Then I check each edge under light to be sure there is no reflection. Then I know the tool is sharp and ready to go to work. My freshly honed tools will cut curlicues in newsprint and they will definitely cut flesh so be careful with them.

That's basically it - hone for the flats.

Hope this helps.


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## mickri (Mar 27, 2019)

Mikey,  That helps a bunch and exactly what I was looking for.  Thanks for the very instructive description on how you hone a tool bit.  I will start practicing.


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## stupoty (Mar 27, 2019)

benmychree said:


> I have seldom felt the need to hone a tool bit; if they are properly sharpened on a grinding wheel of fine grit after having been roughed out on a coarse wheel, they are sufficiently keen edged for most any job.  I save the diamond grit on a slab of plastic for sharpening knives, for that, they are wonderful!  For woodworking edge tools, I use a 3 stone set like the butchers use, finishing with an India stone, got hard Arkansas, but rarly use it.



My bench grinders are a little on the economic side , I find that grinding the tool and then finishing by hand with stones is best for me, I do lust after a real nice grinder with nice rests and no vibration , mmmmm.



Stu


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## stupoty (Mar 27, 2019)

Tom lipton of course has a video on tool sharpening and honing.


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## C-Bag (Mar 28, 2019)

stupoty said:


> Tom lipton of course has a video on tool sharpening and honing.


I love that video, I learned so much. I agree, honing is tricky biz and I've have better luck investing in a bench Baldor knockoff tool grinder and Deckel knockoff tool grinder and a loupe to see better what the outcome is.


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## stupoty (Mar 28, 2019)

C-Bag said:


> I love that video, I learned so much. I agree, honing is tricky biz and I've have better luck investing in a bench Baldor knockoff tool grinder and Deckel knockoff tool grinder and a loupe to see better what the outcome is.



Real nice grinders at a good price are a rare site in the UK , I have two very cheep bench grinders on a stand I have made, they work but I do lust after a nice Baldor style grinder.  Their was one on ebay for ages, with a buy it now of about £400 that was just a bit to expensive and far away for me to impulse purchase but occasionally I would look at it and sigh a little  actualy more like 



I use my nice 4 inch makita angle grinder with a cut of wheel for rough shaping of form tools like threading tools. saves a bit on the dust and grit in my small workshop area.  I generly use my grinders outside which is another reason I havn't got a massive lush grinder as I would then wan't some sort of extraction / grit colection system to avoid covering everything else in abrasive powder 

Stu


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## C-Bag (Mar 28, 2019)

stupoty said:


> Real nice grinders at a good price are a rare site in the UK , I have two very cheep bench grinders on a stand I have made, they work but I do lust after a nice Baldor style grinder.  Their was one on ebay for ages, with a buy it now of about £400 that was just a bit to expensive and far away for me to impulse purchase but occasionally I would look at it and sigh a little  actualy more like
> 
> 
> 
> ...


The one attachment I don't have for the Deckel clone is for lathe bits. But after seeing this Stefan G. vid I went and made the attachment he describes for doing radius work and for doing lathe bits in the Deckel clone. 





I was jones'n for a Baldor type grinder for years watching CL locally and never saw one for less than $400. Then when I'd pretty much given up a clone (HF)showed up last summer for $130 with a diamond wheel and everything! So keep the faith. I don't know how it compares to the real thing but it certainly is way nicer than my Ryobi 8" bench grinder. My "shop" is a two car garage 20'x20' with a 17' south facing roll up door. I almost never work with it closed and like just this morning I was using the tool grinder to grind a carbide lathe bit. I put the grinder in the door way as far out as I can for the fresh air and sunlight. Nothing like working in paradise


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## mikey (Mar 28, 2019)

If you guys want to precision-hone a lathe tool, get an Accu-finish from Glendo. You can put an extremely fine and accurate finish on HSS or carbide lathe tools and inserts with it, not to mention scraper blades. You cannot grind the radius that Stephan showed but for bringing it to a fine edge, yeah, the Accu-finish will do it. I happen to own one of these contraptions and I like it but I do not use it for honing most lathe tools; it is much faster to do it by hand and just as effective for most tools. I do use it to hone my HSS and carbide insert threading tools so I can control the geometry, though. I still need to make a fixture for sharpening gravers but that will go on the Accu-finish once I make it.

For grinding and shaping HSS lathe turning tools, a belt sander is far more effective than a bench grinder. It cuts faster, cooler, flatter and with better control, not to mention the ease with which you can change grits. No danger of a wheel exploding or having to be dressed, either. I used a bench grinder for a decade so I am very clear on which machine is better for this particular task, at least for me. You might want to consider it.


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## C-Bag (Mar 28, 2019)

mikey said:


> If you guys want to precision-hone a lathe tool, get an Accu-finish from Glendo. You can put an extremely fine and accurate finish on HSS or carbide lathe tools and inserts with it, not to mention scraper blades. You cannot grind the radius that Stephan showed but for bringing it to a fine edge, yeah, the Accu-finish will do it. I happen to own one of these contraptions and I like it but I do not use it for honing most lathe tools; it is much faster to do it by hand and just as effective for most tools. I do use it to hone my HSS and carbide insert threading tools so I can control the geometry, though. I still need to make a fixture for sharpening gravers but that will go on the Accu-finish once I make it.
> 
> For grinding and shaping HSS lathe turning tools, a belt sander is far more effective than a bench grinder. It cuts faster, cooler, flatter and with better control, not to mention the ease with which you can change grits. No danger of a wheel exploding or having to be dressed, either. I used a bench grinder for a decade so I am very clear on which machine is better for this particular task, at least for me. You might want to consider it.


Wow, those Accu-finish start at $900, a bit beyond my budget. While I agree with what you say about belt sanders I'd have to make some kind of rest for mine as its horizontal with no rest. It does have a 9" disk sander but the rest was garbage so I took it off. Like with honing I have a hard time keeping the angle true through the range of the stroke freehand. And with the belt and disk freehand tends to dig in on the leading edge. I get this is where superior technique comes in. 

The Baldor clone with the green stone on one side and the super fine diamond wheel for finishing on the other has gotten me functional. I don't know if the Baldor tool rests are as funky to adjust as my clone. So far that's my only beef with it. Sure would have been nice to have some kind gear mechanism instead the sloppy setup it has. The silly little mitre gauge leaves much to desire too. But beggars can't be whiners I guess.


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## mikey (Mar 28, 2019)

If yours is a tool grinder vs a bench grinder then they work fine; I've used one once and it was a Baldor. Since you're grinding on a flat face the grind is pretty good except for the rake angles; those were hard to do because of the lack of support on the side of the wheel. Still, they are superior to a bench grinder. In my opinion, a good belt sander is several steps above them for HSS lathe tools, though. 

Someday, if you decide to get serious about HSS lathe tools, consider a 2x72 belt sander.


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## C-Bag (Mar 28, 2019)

mikey said:


> Someday, if you decide to get serious about HSS lathe tools, consider a 2x72 belt sander.



Ok Sensai Mikey please enlighten the grasshopper what the complete 2x72 HSS lathe cutter rig looks like. I and probably countless others would love to know. And please I'm not being facetious here. Too many times stock pics without pertinent details are posted leaving us noobs scratching their heads. I truly bow to your expertise as demonstrated by your extensive thread on cutters that is in the stickys here on one of the forums.


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## mikey (Mar 28, 2019)

It appears that I implied that I was speaking down to you or dissing your stuff. If that is your perception then that is not what I meant. I simply meant that I've used just about every kind of commonly available grinding tool to grind lathe tools on and the most efficient tool I've found is a belt sander. 

In point of fact, I don't own a 2X72 yet. I own a 2X42 but I've used it to grind hundreds of lathe tools so I actually have a basis for my opinion. I've detailed my own set up here. What is the difference? Speed and efficiency. The bigger machine will grind the tool faster, possibly cooler ... but not better.

Grinding tools is not difficult. The many guys who went from zero experience to grinding really nice tools in the span of a single thread, our model tools thread, is proof that it is not difficult. However, a belt sander makes it so much easier to do, which is why I suggested that type of grinder to you. Two weeks ago, I had the chance to grind a lathe tool on a bench grinder outfitted with CBN wheels and while it did the job better than a standard wheel, I still feel that a belt sander with a ceramic belt, a good platen and a good tool rest is a better machine for tool grinding. There is no doubt that most lathe tools across the globe are ground on bench grinders of some type. That, however, is changing as more and more of us discover the advantages of a good belt sander.


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## C-Bag (Mar 28, 2019)

I was afraid I was being to flippant Mikey, You were not talking down to me, I was trying to give the virtual deep bow. I KNOW you know what you are talking about, I just would like to see like the hard pix of what the rig looks like.

Thanks for the link.


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## mickri (Mar 29, 2019)

I have to second Mikey on the belt sander.  When I started this journey I was using my 4" makita highspeed grinder.  The tool bits barely worked.  Then I picked up a Dunlap 6" bench grinder at a garage sale.  Things got much better but it was still a chore to get things close to right.  Then I found a Delta 1x42 belt sander in a consignment shop for $40. 




 What a difference.  Grinding a tool bit now is no big deal.


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## Z2V (Mar 29, 2019)

C-Bag, I’m new to the hobby and started following Mickey’s tool grinding thread. I ground a few cutting tools with an 8” bench grinder. I made adjustable work tables for the grinder and it worked pretty good. After reading all the talk about the belt grinder I decided to make one of my own. I scrounged a motor and board from a treadmill, picked up some raw materials and put one together. It’s not as polished as some but with a 3 hp motor it sings. It is probably the most often used tool I have. I will say that without a doubt, it’s much easier to grind a cutting tool with a belt grinder than a bench grinder. 
YMMV
Here’s my 2x72


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## mmcmdl (Mar 29, 2019)

Haven't honed a tool bit in years , and never a HSS in my life . Cemented carbide tools were diamond ground a degree or two more than required , and touched on the oil hone at your desired finish angles . When looking under a loupe , you could not see the point of the tool it was so sharp . Our old time Hardinge guy taught this to all the apprentices over the years , but as the lathes got bigger and carbide insert tooling came out , it's gone by the wayside . Now-a-days , if I want a dead sharp point ( which isn't very often other than maybe cutting plastic ) , after grinding with carbide touch it up with a fine diamond file . Your edges should look like a mirror when finished and your point should kinda just disappear to nothing . ( if that makes sense ) .


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## mikey (Mar 29, 2019)

C-Bag said:


> I was afraid I was being to flippant Mikey, You were not talking down to me, I was trying to give the virtual deep bow. I KNOW you know what you are talking about, I just would like to see like the hard pix of what the rig looks like.
> 
> Thanks for the link.



Thanks for the respect, although not necessary. I know what I know only because I made every mistake that can possibly be made and I sorta' learned a thing or two in the process.

I haven't seen Chuck's tools in the flesh but I have seen @Z2V/Jeff's tools and they are every bit as good as what I can grind. Jeff is good, no kidding, and so is @ttabbal (I've seen his tools in my hands, too). Both are relatively new to tool grinding and I think the belt sander really helped them master the task. So, again, something to consider ...



mmcmdl said:


> Haven't honed a tool bit in years , and never a HSS in my life . Cemented carbide tools were diamond ground a degree or two more than required , and touched on the oil hone at your desired finish angles . When looking under a loupe , you could not see the point of the tool it was so sharp . Our old time Hardinge guy taught this to all the apprentices over the years , but as the lathes got bigger and carbide insert tooling came out , it's gone by the wayside . Now-a-days , if I want a dead sharp point ( which isn't very often other than maybe cutting plastic ) , after grinding with carbide touch it up with a fine diamond file . Your edges should look like a mirror when finished and your point should kinda just disappear to nothing . ( if that makes sense ) .



I haven't done much grinding on brazed tools other than to get and keep them sharp. I think a lot can be done with the geometry of those tools but you need a carbide grinder to do it, which I do not have. Used to be a guy here named Chris Poulsen (sp?) but I drove him off it seems. He seemed to know a lot about this subject and I wish he stuck around; I think we could all have learned a lot from him.


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## mmcmdl (Mar 29, 2019)

Hey Mike ! You know , I haven't seen tools around that I had back in the tool and die days . Wet diamond wheels , oil hones , lapping plates etc . We had a machine similar to a sand/bead blaster that was a mixture of liquid and media . It was the most used accessory in the plant . I believe we referred that as the water hone . Haven't seen one around and haven't heard about anything similar to it . Maybe it was shop made ?

We also had a grinder for carbide that " sparked " the material off , but can't remember what we called it . It did not like when you hit the steel shank below the insert , I do remember that . You got a shock from it . 

We made up a machine to polish the ID of pipe by using oil and media and pushing it thru the pipe . Back and forth for hours . We then switched over to burnishing which was quicker and better results .


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## savarin (Mar 29, 2019)

I just use the standard grinding wheels to edge my braised carbide tools.
Slow, no sparks but does do the job.
Almost like dressing the wheel with the carbide.


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## mikey (Mar 29, 2019)

mmcmdl said:


> Hey Mike ! You know , I haven't seen tools around that I had back in the tool and die days . Wet diamond wheels , oil hones , lapping plates etc . We had a machine similar to a sand/bead blaster that was a mixture of liquid and media . It was the most used accessory in the plant . I believe we referred that as the water hone . Haven't seen one around and haven't heard about anything similar to it . Maybe it was shop made ?
> 
> We also had a grinder for carbide that " sparked " the material off , but can't remember what we called it . It did not like when you hit the steel shank below the insert , I do remember that . You got a shock from it .
> 
> We made up a machine to polish the ID of pipe by using oil and media and pushing it thru the pipe . Back and forth for hours . We then switched over to burnishing which was quicker and better results .



I envy you, Dave, for having seen and done this kind of stuff. I have all the inserted carbide stuff but I don't use it often. I much prefer HSS and actually also use brazed carbide because as you said, you can get it really sharp. Thank you for sharing!



savarin said:


> I just use the standard grinding wheels to edge my braised carbide tools.
> Slow, no sparks but does do the job.
> Almost like dressing the wheel with the carbide.



Thanks, Savarin. I think Jim Dawson uses a standard grey wheel to do brazed carbide, too. Maybe one day I'll pull my bench grinder out and give it a try!


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## C-Bag (Mar 29, 2019)

It seemed all I saw was sharpening lathe bits on a bench grinder. It never made sense to me that you are trying to achieve a flat angled surface on a round wheel. That 8" bench grinder led me down the rabbit hole diversion of trying to balance the infernal thing. It made such a racket and vibrated so bad it took an already scary machine and made it terrifying. I tried making better hubs, better wheels, balancing fixture yadda yadda. Finally found some balancing hubs after months of this crap. About this time the Baldor clone fell into my lap. It needed balancing too but got it squared away. But I would have been so far ahead of the game if I would have known and gone the belt sander route no doubt. It bypasses so many of those problems. If the clone ever dies I'll go belt.


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## Cadillac (Mar 29, 2019)

Ive seen where people install a flat diamond disc on the side of a bench grinding wheel. The problem I see with that is speed it will probably burn up the diamond disc. 
 I have a nice delta slow speed wet grinder I had gotten back in my woodworking days that I plan to replace the large stone with a hub/backplate for the diamond discs. What had been holding me up is cutting a hole for the motor shaft which is a D shaft. Nice grinders and way less than a glendo.


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## mikey (Mar 29, 2019)

Good idea, Cadillac. Let us know how it works out. I thought about doing that same thing but I couldn't find a variable speed DC gear motor with an angular contact bearing to take the axial loads. I was going to build something with an AC bearing that was driven by the DC motor but never got around to it.


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## MSD0 (Apr 1, 2019)

mikey said:


> If you guys want to precision-hone a lathe tool, get an Accu-finish from Glendo. You can put an extremely fine and accurate finish on HSS or carbide lathe tools and inserts with it, not to mention scraper blades. You cannot grind the radius that Stephan showed but for bringing it to a fine edge, yeah, the Accu-finish will do it. I happen to own one of these contraptions and I like it but I do not use it for honing most lathe tools; it is much faster to do it by hand and just as effective for most tools. I do use it to hone my HSS and carbide insert threading tools so I can control the geometry, though. I still need to make a fixture for sharpening gravers but that will go on the Accu-finish once I make it.
> 
> For grinding and shaping HSS lathe turning tools, a belt sander is far more effective than a bench grinder. It cuts faster, cooler, flatter and with better control, not to mention the ease with which you can change grits. No danger of a wheel exploding or having to be dressed, either. I used a bench grinder for a decade so I am very clear on which machine is better for this particular task, at least for me. You might want to consider it.


We have one at work at they work great.


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## Tozguy (Apr 1, 2019)

Yet another option for grinding bits;
Convert a used circular saw blade for grinding by adding a stick-on sandpaper disc on it.
Use the blade tilt and protractor to set angles. Surface speed varies depending on how close to the centre you hold the bit.
Grinds very fast but not too hot. As with any grinding make sure you quench regularly.
Works so well that I bought some metal sanding discs and put different grit on each side of the blade.
For honing, unplug the saw, adjust blade to the angle required. Rest the hone against the blade and with bit flat on the table work by hand.


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