I’ll be straight with you – I was sceptical when I first heard you could sharpen planer blades with sandpaper. I mean, it sounds kind of janky compared to using fancy water stones, right? But let me tell you, it totally works and can get your blades just as sharp. Let me walk you through the steps I use so you can try it yourself.
First up, you’ll need some sheets of sandpaper in a range of grits – I’d grab some 220, 320, 400, and 600 grit. Make sure to cut or tear the paper into strips a little wider than your planer blade. You’ll also need some rubbing compound and a strip of leather later on.
Start by taking the blade off your planer and giving it a good wipe down to get rid of any gunk. Remove any paper shims too while you’re at it. Those just take up space we need for sharpening.
Lay the sandpaper on a flat surface and hold the bevelled side of the blade flat against it. I like to start with the 220 grit. Draw the blade back toward yourself with good even pressure. Do this about 10 times. When you’re done with each grit, wipe the blade clean before moving to a finer grit.
Work your way up through the 320, 400, and 600 grits the same way. You’ll notice the scratches from the previous grit disappearing as you go. This is good! It means you’re polishing your blade to a razor’s edge.
Once you’ve worked through all the grits, grab that leather strip and rubbing compound. Put a thin layer of compound on the leather. Then pull the blade toward you along the leather, going edge-first, just like with the sandpaper. Do this about 10 times.
When you’re done, wipe off any remaining compound and feel along the blade’s edge to make sure you didn’t miss any spots. Now slide a piece of newspaper down along the edge. If it slices clean, you’ve got a sharp blade! If it snags, just repeat the process until it glides smoothly.
See, sharpening planer blades with sandpaper totally works! It just takes patience and working through the grits methodically. Once you try it, you’ll be surprised how sharp you can get those blades. Your planer will glide through wood like butter when you’re done.