Episode #36: Grinding Without Fear

Note: All of my old podcast videos have been moved to my YouTube channel.  You can now watch this video here:

https://www.youtube.com/watch?v=bqlYBzfxMyQ&t=25s

Advertisements

17 thoughts on “Episode #36: Grinding Without Fear

  1. Thanks, I enjoy all of your posts. Just goes to show that you don’t need to spend a fortune to be able to sharpen tools. Love that expensive tool rest!

    Chuck

  2. Excellent video Bob. Thanks a lot. You’ve saved me a lot of time and money with this one. Actually, I get a lot from all of them. I sure appreciate you giving so generously of your time and knowledge.

    -Jimmy

  3. Boy, getting through your video was a real grind! Okay, okay, don’t hit me! Seriously though, I found the information and demos quite enlightening. I remember watching Frank Klausz in his Hand Tools video using a grinder for the initial sharpening step in sharpening his tools. I was wanting to do it Frank’s way, but I’ve read so much since then that shuns the grinder. However, after seeing your video, I found it reassuring and confirming to just go ahead and get a grinder.

  4. Great as always! I was hoping, however, that you’d mention how you set your angles. Is your rest adjustable? Do you compare to a gauge of some sort?

    • Yes, my tool rest is adjustable. The platform is mounted to the post using a carraige bolt and wing nut. I have one of those circular angle checker things, and it stinks, so don’t bother getting one. What I typically do is just set a bevel gauge to the desired angle and check the tool with that, if I check at all. I have a bunch of angles scribed on a scrap piece of wood that I use to set the bevel gauge. Basically, it’s a shop made protractor.

      Usually, though, I’m just re-establishing the hollow grind at whatever angle the tool is already at. I don’t pay a lot of attention to exact angles. I just grind to the shallowest angle that will still hold a good edge without chipping. That typically means somewhere between 25 and 35 degrees for most of my edge tools. I then hone at the same angle as the grind, except for my mortise chisels. My mortise chisels are ground very low (like 20 degrees) with a very high secondary bevel (like 35+ degrees), because that’s how they came when I got them, so I kept them that way.

  5. Great podcast. Thanks. I am about to get a grinder myself. I plan to follow the advice of The Schwarz and get a blue wheel. What grit would you suggest for most tools and do I need a balancer?

    • Get the coarsest wheel you can, regardless of what color it is. I don’t go over 46 grit, and 36 grit is even better. Coarse wheels grind faster and cooler.

      You shouldn’t need any kind of balancer. Just use the wheel dressing tool to true the wheel to the arbor the first time you use the wheel. Don’t grind until you true the wheel.

  6. Very helpful podcast. It might even get me near my grinder!

    Question: I have a norton 60/80 (medium grit) wheel that I bought a while back, thinking it might be the right grit range. I know you recommend not going beyond 46 grit, but is the 60/80 wheel still better than the white ones that came with my slow-speed grinder? In case it matters, I have a slow-speed 8″ grinder.

    • Jacky,
      With a grit that high, there is a lot more chance of overheating the tool. I had an 80 grit white wheel at one time. The white ones are supposed to run cooler since they are more friable. However, that wheel generated a lot of heat. Just to clarify about the grinder speed, an 8″ slow speed grinder is still moving just as fast as a 6″ high speed grinder at the tool. The larger diameter of the wheel means that even though the RPMs are lower, the speed at the outside edge of the wheel is the same. So your 8″ slow speed grinder actually grinds at about the same speed as a 6″ high speed grinder. If you decide to go with your 60/80 grit wheel, use a VERY light touch and cool the tool in water before you think you need to. Those wheels will take a tool from cool to too hot in a split second because of the increased friction the finer wheel generates. I’d recommend a coarse wheel. It doesn’t have to be expensive. I am currently using the inexpensive wheels from Grizzly. It’s the same brand that is carried by Woodcraft. Here’s an 8″ 36 grit version of what I have on my grinder http://www.grizzly.com/outlet/8-x-1-Grinding-Wheel-A36-3-4-Bore/H8881.

  7. Do you have any more info on your tool rest.
    I want to make one for my 8″ Grinder

  8. Bob,

    Thanks for this one. I’d spent so much time fumbling around trying to get a proper hollow grind that I gave up on the technique. Now it’s time to give it another go.

  9. Bob — great video, thank you. I’ve just got into grinding + free-hand honing, and enjoying it so far. I did go with a Schwarz-approved blue wheel and find it works no problem, though higher grit than you recommend. Though I bet I’m generating more heat than you. What I loved about the video is seeing where your fingers are during grinding – right up close to the edge which means you feel when the tool is getting hot and needs dunking. If your fingers are the close towards the edge, than there’s no way to overheat the tool. I’m going to start getting a little closer to the front as I grind and see how that goes. Thanks.

  10. Great video Bob. One question tho’… why did you remove the wheel shrouds on your bench grinder? My concerns are that it would be dangerous to operate with out them. Are these concerns valid? Thanks

    • Yes, it is very dangerous to operate the grinder without the safety shrouds. This is a case of don’t do what I did.

      It’s kind of a long story. The grinder had been turned into a dedicated buffing station about 8 or so years ago when I was restoring a vintage Harley. I had a hand cranked grinder for the shop, so wasn’t using the power grinder for grinding. I removed the shrouds because the buffing wheels I was using wouldn’t fit with the shrouds on. A couple of years later, we moved. The shrouds got lost in the move and the arbor on my hand cranked grinder got bent. So the hand crank grinder no longer works well, forcing me to go back to the power grinder for heavy material removal. However, I avoid grinding when I can because of the current safety issues with the tool in its current state.

      I have plans to build an enclosure for the entire tool that will make it safer to use once again, unless I find another hand cranked grinder in good shape that runs smoothly first. I just haven’t gotten to making the enclosure yet. Instead, I’ve been avoiding the grinder.

  11. Bob, great video on using a high speed grinder. Like the others, I was always afraid to use a high speed grinder in fear that I would damage the blades. After watching your video, I am more comfortable than ever using the grinder. Question: How often do you grind a hollow bevel? Is it every time you sharpen? or just when the bevel needs to be regrind?

    Thanks Bob.

    • Hi Scott,

      Grinding is really only necessary to lower a bevel angle or remove damage to an edge. I typically re-grind when I have honed away the entire hollow just to make honing faster but even then it’s really not required as the whole bevel can be honed. It takes longer though. I try to grind as infrequently as possible to save valuable steel and tool life.

Comments are closed.