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Sharpening Stones for Chisels and Plane Blades

I wrote this because I want you to know how good diamond stones are. Don’t buy anything else! You can see the one that I use and recommend for sharpening many chisels and plane blades quickly here.


This is a summary of my experience using different sharpening stones for chisels and plane blades. I did plan on writing a long article about scientifically weighing up the pros and cons, but to be honest I found the winner quite quickly and it was head and shoulders above the rest.

If you want to read more detail on each of the stones and my experience I have included it below.

Diamond Stone

The pros:
  • Hard and tough
  • Keeps a flat, even face (even after plenty of use)
The cons:
  • Price (more expensive)
  • You need to use an oil as opposed to water (not much of a con)

The reason I like Diamond stones so much is that they are so hard and it makes the difference. Particularly for people like us who need the job done, in a smart timeframe.

Because they are harder, you can grab them out of storage and start sharpening pretty much right away, simply becuase you know that the stone is flat.

Norton 325 grit diamond stone - Sharpening stones for chisels

This is the one that I have got. I got it from total tools quite a few years ago (couldn’t find it when I looked again) but you can find more details of it on Amazon here.

All diamond stones will have the same advantages though, and will be more expensive than the other two options.

The one I have is a real workhorse and hasn’t missed a beat in years. It’s 325 grit which is a lot lower than the other stones. This does help in my situation (as a woodwork teacher), with fast sharpening.

I have never needed a sharper edge, but you can use wet and dry sandpaper on a flat surface if you need to.

Whetstone

The pros:
  • Your using water so there’s no oil. (Not much of a pro to be honest)
  • More than one coarseness on the stone which helps get a sharper edge
The cons:
  • You need to dunk the stone for about 10 minutes before you start, so there is a little forward planning.
  • Whetstones are a little soft so you chisel might make a dip in it.

I used a whetstone with my kitchen knives as well as some chisels to test it out. The one I have is made from Corundum.

Sharp Pebble Whetstone - Sharpening stones for chisels

It did come with a few extras like a little stand and rubber mat so the water stays in the one place and doesn’t move around.

When I started using it (particularly with the knives) I noticed that i was removing some of the stone. This isn’t good, because that is going to create an uneven surface, which effects sharpening.

Half of the sharpens were good, the other half I think the blade had rounded over. Which in my book means I need to put the chisel on the grinder and start a new edge.

Oil Stone

The pros:
  • More than one coarseness on the stone which helps get a sharper edge
  • Not as soft as the whetstone
  • Was the cheapest of the lot
The cons:
  • The face did get a dip in it quite quickly

The oil stone I have at work is aluminium oxide. The company we buy tools and equipment from only sells one type of sharpening stone, so this was it.

It didn’t take long for mine to get a dip in the middle of my oil stone.

To get it flat I was told to get some fine sandpaper (1200 wet and drt) put it on something flat (i.e. melamine chipboard) and keep rubbing until the stone is flat.

The problem is that if the dip is of a noticeable size, it can take ages to get it completely flat.

Which renders the stone pretty much useless in my experience.

Summary

Spend the extra money and get yourself a diamond stone.

The one I have is here but you can get them from many different places in different shapes and sizes.

Thanks for reading…

this guide on sharpening stones for chisels. You can see more of my tool related posts here.

Below I have put some frequently asked questions about sharpening chisels to help.

FAQ’s

What oil can you use?

I used parrafin oil (white mineral oil) because I had it lying around.

Any type of oil I think would be ok, as long as it won’t go rancid over a period of time, like many cooking oils will.

What grit should I look for in a stone?

My diamond stone is 325 grit. I find this is plenty. Many of the other stones are a lot higher.

This higher grit does give a sharper edge but in my situation (with high school kids using the tools most of the time) I haven’t noticed it.

If for some reason you really want a sharp edge, the Japanese plane makers are where i’d look.

How do I sharpen a chisel on a sharpening stone?

Put some oil on the stone and keeping the blade flat on the stone make the figure 8 a few times. Flip the chisel over to the other side and do the same thing.

Repeat until you get a nice straight edge. Finish on the flat side (as opposed to the beveled side) to make sure it is smooth and doesn’t scratch your work.

Here’s a video of me sharpening a plane blade. It’s the same process but a little easier with the plane blade (because it is bigger)