A Simple Hollow Grinding Jig




This is a jig I threw together from things in my shop that makes it easy to create hollow-ground knife bevels. I would have made an instructable out of it, but I don't have any pictures of the process and it's pretty easy to see how the thing goes together any way. The metal widget with the springs is there just to make sure the work rest (the piece of cherry with the c-clamp on top) doesn't move around and change the distance of the knife to the wheel. The c-clamp itself is cut down so I have a better view and control of the knife while grinding. I can also move it around to accommodate blades of different widths and thicknesses.

This jig could also work for with a bench grinder with a hard wheel. The roller that makes my hollow edge only has a 4-inch diameter, which is a little small for single edges...but it's the best I've got right now. And the blades end up devilishly sharp.

The last few images are of a knife I recently made with this jig, what I'm calling a "camp seax." Straight edges are easier. If you've seen my knifemaking Instructable, you can tell that I've greatly improved in a couple years.

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Be the First to Share


    • Instrument Contest

      Instrument Contest
    • Make it Glow Contest

      Make it Glow Contest
    • STEM Contest

      STEM Contest

    15 Discussions


    Reply 6 years ago on Introduction

    Definitely. It's a little beefier than the tool rests that come with most grinding wheels, too.


    8 years ago on Introduction

    I'd like an instructable on how to build your grinder. Where'd you get that?


    Reply 8 years ago on Introduction

    All I bought were the springs, the rest was scrap lying around...so I spent about $2.50. YMMV, especially if you don't weld. I'd guess about $20 for all materials.


    Reply 8 years ago on Introduction

    There's a lever to the side of the platen that tilts it laterally--part of the grinder, though, not the jig.


    Reply 8 years ago on Introduction

    Oh OK I thought you'd made the whole belt sander attachment I see it now you made the tool rest. I've made a few tool rests myself. I've modified this one a little more since this picture but this is the general idea:


    For hollow grinding chisel and plane blades mostly.

    I made this other one first though sort of a proof of concept before I committed to doing it in steel:


    9 years ago on Introduction

    This is pretty good, and I think if you set this out as an instructable with notes to go with each of your pics, you would have a decent 'ible. None of your parts look difficult to make. Great work.