Sharpening wider blades

[Phillip Ngan]

I'm asking this question on the Neanderthal forum instead of the general forum because people here are so passionate about sharpening.

Can I use my bench grinder and shapton glass stones to sharpen the blades on my jointer and thicknesser. The jointer is 6" and the thicknesser is 12". If not, how does one go about sharpening these blades at home? How sharp do these blades have to be? How do tell when the right time to sharpen is?

[David Weaver]

They may get so nicked up they're not worth fooling with. Otherwise, you'll need to sharpen them probably before they seem to get dull.

You would be better served by a jig that held the blades on the bevel angle against a flat surface (like something appropriate for lapping) that's got psa adhered paper to it - that's something you'll have to make (the jig). Something slightly steeper than the primary bevel is what I'd do, and take care to get an even second bevel along the length.

Always thought that would be interesting to do, but stopped using power tools before getting there.

You might be able to do a secondary bevel on the short jointer blades on the shapton a couple of times, but if you do it freehand, a couple will be it. The planer blades will be too long to do on the shaptons, and you'll find that since they're HSS, they probably won't sharpen like you'd like them to in terms of ease. Fresh sandpaper is a better choice.

[john brenton]

some craftsman planer blades for an idea that I had (that failed), but I was able to hone them up to hair splitting sharpness fairly easily. The bevel width is wide enough to where sharpening freehand wasn't a balancing act, and the bevel was already pretty close to dead flat.

I used very small stones too (2.5" x 4"). I just honed going side to side instead of pushing forward and backwards.

[Russell Sansom]

In his sharpening book, Ron Hock concurred with my thought on this some time ago: If the blades are available, buy new. Otherwise: send them out to be sharpened or use a Tormek ( or Jet clone ). The Tormek works well, but with buying the jig ( $173 ) and the time involved, it is not an economical proposition. My used Tormek came with the jig and my one shot at sharpening my own was a great success. But then I figured at $31 a set for my DJ-15 ( 6" blades ), it is cheaper to buy new.