How to Sharpen Hand Planer Blades

How to Sharpen Hand Planer Blades

There’s an old story, often used by Daoist and Buddhist teachers, about an aging butcher in a small village.  He knew his working days were coming to an end, and so he took in three apprentices to teach them butchery as his replacements. 

Each night before leaving, the apprentices would sharpen their knives on honing stones to prepare them for the next day of work.  But, the aging butcher didn’t.  At the end of the first week, the apprentices asked him why he didn’t sharpen his knives.

“I cut where there is no bone.  I work in collaboration with the animal, who guides me through the right spots.  So, I never lose my sharp.”

Unfortunately, wood is not quite so accommodating, and the blades of our hand planers do lose their sharpness over time. Sharpening planer blades, though, is as easy as sharpening a butcher’s knife. We’ll walk you through two methods for doing so in this article.

Using A Honing Guide To Sharpen Your Hand Planer Blades

Let’s talk about water stones, jigs (both commercially available and home-made), honing guides, angles, sharpening kits, bevels, metal surfaces, stone surfaces, and a few more things about sharpening your hand planer blades:

  • Water stones. Sharpening stones, sometimes called whetstones, are blocks of stone used to sharpen the edges of metal tools such as knives, chisels, and hand planer blades through grinding and honing.  They come in a variety of shapes and sizes, as well as number ratings that identify coarser and finer honing surfaces.  You will likely want to have a coarse, medium, and fine grit set of stones.
  • Jigs. A sharpening jig is used to hold a blade at a consistent angle while you sharpen it, whether it be a chisel, a hand planer blade, or any other woodworking tool. 
  • Honing Guides. Virtually interchangeable with a jig, a honing guide will hold the blade being sharpened at a consistent angle.

You want a sharp edge on your hand planer blade so it does not gouge the wood’s surface and make the planing movement smoother and easier.  You also want the cutting edge to be at the proper bevel angle.

So, How Do You Keep Your Planer Blades Sharp?

You’ve assembled the sharpening guides and are ready to put a good edge on the blade.  Begin by removing the blade from the hand plane and fitting it into the jig or honing guide.

First, make sure your stone surface is flat.  Having a diamond honing stone is helpful to flatten the water stone’s surface, and in the video at the end of this section, you’ll find an excellent method of determining flatness.

Keeping Blades Sharp

Wet the stone you will be using, either by spray bottle or simply by dipping it into water. You’ll want to be following the instructions that came with your hand planer on the proper angle to maintain the cutting edge of the blade and setting the honing guide or jig accordingly.

Draw the blade back toward you over the stone’s surface.  Helpful tip: after honing the entire blade, draw it back just a few times over the stone’s surface, applying just a little extra pressure on one side of the blade and then the other.  This will keep the blade’s corners from digging into the wood’s surface during planing and gouging out a small strip.

Begin the process of sharpening on the coarse stone, moving to the middle and finally to the fine grit to finish.  The honing guide or jig and a bit of pressure from you as you draw the blade back along the stone’s surface will keep the blade flat against that surface, ensuring an even sharp across the blade, assuming you’ve flattened the stones’ surfaces.

This step-by-step process is not time-consuming and can be accomplished relatively quickly.  This assumes, though, that you regularly sharpen the blade.

Remember, too, that in the sharpening process, you are removing metal from the blade.  A little bit of slurry will appear on the stone’s surface and is not a concern – it’s simply some of that metal mixing with the water you applied to the stone.

Here are 2 videos that should help:

1) This video will take you through the entire process we’ve just described and does so very well.  It also answers the question:  How sharp does a planer blade need to be?  It seems the answer is “scary sharp.”

We like this video also because the YouTuber takes the time to discuss how to set bevel angles with just a little math but well-explained with diagrams.  He answers for you the question:  What Angle Do You Sharpen Hand Planer Blades?

2) And for those of you who want to do everything for yourself, here’s a fellow who makes his own honing guide from a block of wood.

Using Sandpaper to Sharpen Your Hand Planer Blade

Yes, you can use sandpaper to sharpen your planer blade. It’s the same principle as using a water stone, only in this case, you are using sandpaper.  As with the use of water stones, you’ll want a variety of grits, from 220 to 600. 

Other elements in this process include a rubbing compound and a leather strip.  If you’ve ever had a shave at a barbershop, you’ve seen the leather strop the barber runs the shaving blade over before he brings it to your face. It’s the same thing here.

Remove the blade from the planer.  Make sure the blade is clean, and remove any paper shim on it (the paper shim acts as a buffer for the blade within the housing of the planer and closes any gap between the blade and the planer frame). 

Cut the sandpaper into strips a bit wider than the blade and lay the sandpaper on a flat surface.  Hold and press the bevel side of the blade onto the sandpaper and draw it back toward you several times, beginning with the 220 grit paper and moving on to a 320 grit, then a 400 grit, and ending with the 600 grit paper.  Be sure to remove any grit on the blade as you move from one grit to the next.

Add a thin layer of rubbing compound to the leather strip and draw the blade toward you along the leather several times.  Wipe the blade off, and feel carefully along the edge to make sure you didn’t miss either grit or rubbing compound.

The blade should be very sharp, so be careful.  Check it by testing the edge on a piece of newspaper.  If the cut is clean, the blade is ready to be put back into the planer; if the cut is ragged, repeat the process for the sharpness you need. 

It’s a quick and cheap way to sharpen your planer blade.  We even found a video for you, the newbie woodworker, that plays this process out. 

We’ll warn you there is a little geometry in the video, but in an excellent way to help you understand the process and the purpose of planers.  And, don’t worry, there’s no exam or pop quiz after watching it.

It’s not a daunting task, as you have now learned. 

Two Final Tips

  1. Sharpen your hand planer blade often if you use it often.  A sharp blade will result in a better project outcome.
  2. Be careful.  Each of these methods will give you a very sharp blade. 

Keeping your blades sharp, whether you’re a butcher or a woodworker, will make your work so much easier.