how do you properly hone a tool bit?

[mickri]

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.

 

[Z2V]

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

 

[mmcmdl]

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 ) .

 

[mikey]

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 ...

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.

 

[mmcmdl]

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 .

 

[savarin]

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.

 

[mikey]

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!

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!

 

[C-Bag]

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.

 

[Cadillac]

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.

 

[mikey]

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.