It is very important to keep all of your sharp tools sharp. Of course, for some tools, that is much easier said than done. Tools like the drawknife are incredibly unique in shape and overall design. This means that sharpening them won’t work just like your everyday knife sharpening might.
Sometimes, sharpening procedures take a little bit of ingenuity. And the good news is that there is typically more than one option out there that you can base your sharpening tactics on.
In this guide, we will walk you through exactly all of the details that you need to know to sharpen a drawknife.
Why is the Drawknife So Unique?
Drawknives have a very interesting shape and appeal to them. They are used primarily for working with logs and large pieces of wood. In fact, the drawknife was actually designed to peel the bark off of a log and get to the wood beneath.
This could be important for someone who is using wood carving or perhaps other woodwork that needs real wood without bark.
This knife actually looks quite a bit more like a handsaw when you check out the details of it. It has a long blade that is positioned horizontally between two handles.
In most cases, the handles are positioned folded down from the blade but at a slight slant. This allows you to hold the blade in two hands at an angle and pull it along the surface of whatever you might be working on. Whether you are peeling bark or some other purpose.
As you pull the drawknife towards you, it just shaves from the surface of the wood. You continue this pulling motion in strokes until you’ve achieved your task.
The drawknife has a beveled edge that is exactly 33 degrees in most cases. There is certainly more than one way to sharpen it so you might choose your method based on what you are comfortable with or the tools you have available to you.
That steel blade can certainly handle a lot of wear and tear. You can expect it to get pretty banged up over time. However, there comes a time when you will need to sharpen the edge to avoid having to wrestle with the drawknife to get anything done!
The primary ways to sharpen a drawknife are by using either a grinder, a file, or even a whetstone. We’re going to walk through mostly using the grinder but we will touch on the other methods as well.
How to Sharpen a Drawknife with a Grinder
One of the easier ways to sharpen your drawknife is to use a grinder. This is what most woodworkers would recommend. The thing is, you won’t just be sharpening the blade. There is other work that must be done here in order to restore your drawknife to working condition.
It’s not just automatically taking the blade to the grinder wheel. You’ve got to set your grinder up right, make sure you have the right stuff on the wheel, and then prepare the backside and front side of your knife.
All of that is before you even actually get the sharpening part of this story! So let’s walk through the details of the process, shall we?
1. Prepare the grinder
You can use what you feel is best for the grinder. You also might have a different size of a grinder than what some would recommend. That’s totally fine. The key detail is that your grinder needs to operate at a medium to low speed and be able to run at that speed for a while without overheating.
You know your grinder best so if you feel like it can’t handle it, you might also need to work in spurts.
Apart from having a grinder, you need to have a wheel on it with decent grit. Outside of the grinder, you might also need a coarse diamond plate and a whetstone as well. Don’t feel like you have to use exactly the same thing as everyone else. Try to figure out how to make what you have work or pick up some accessories along the way to be prepared for sharpening things as needed.
You can use a grinder to sharpen a lot of different tools so it can come in handy.
We recommend using a grit of 40-60 for the grinder wheel. The size of the grinder wheel really doesn’t matter but the drawknife can sometimes be pretty wide so if you have an 8-inch or something along those lines, it can be helpful!
2. Inspect the drawknife
Now, start with a thorough inspection of the drawknife. Look at the top of the surface rather than the blade. Look at the back as well.
Here, you’re not going to be looking for sharpness but rather imperfections in the steel. Check the curve of the piece. Does it curve evenly? If the curve is uneven, you may need to make some adjustments.
Look for nicks, dents, burrs, and other similar issues on the surface of the steel. You want to make the steel smooth so take a little bit of time here to work out these details and make sure the steel surface is smooth, particularly on the topside of the drawknife.
Don’t skip this step. It will make a difference later on in the process.
3. Work out the back of the knife
Now you also need to check the backside of the knife. While you may have already checked this area for imperfections as we mentioned above for the front of the knife, you have one more duty to handle here on the backside of the blade.
It needs to be flattened out. If you’ve ever sharpened a chisel, you might already realize the importance of this. You also flatten out the back of those blades. It’s the same thought process here.
The back of the blade needs to be mostly flattened. This will help to accommodate the sharp edge and bevel later in the process. You can use your diamond plate for this. We recommend a coarse stone or plate so flattening doesn’t just take forever.
You should also use your whetstone while you are in this phase. When you push the whetstone across the back of the blade, only push it forward repeatedly. Don’t pull it backward.
Here’s the trick on the drawknife though. You want a MOSTLY flat back. You’re going to flatten the back but on the ends of the back of the blade, add just a hint of a camber angle. This will just help your blade glide more smoothly when you’re using it.
4. Sharpen the blade
If it is helpful to you, you can always build or add a jig to your grinder to help you out during the sharpening process. The reason this can be helpful is that you can set the jig at the angle of your bevel (which is 33 degrees for this purpose) and then the jig will hold your blade steady at that angle.
It just helps eliminate errors from an angle getting off or you slipping while you’re sharpening. A jig is not required but we think you will find it can make a world of difference. Basically, the jig works as an extension of the rest on the grinder.
Now, once you’ve got your angle all set up and your jig in place, you can turn on the grinder and start moving your blade along the wheel. You will just need to exert a slight amount of pressure against the wheel. Don’t press hard.
Just run the blade over the wheel from high to low several times. It creates a longer movement so the blade won’t get too hot too quickly. After a few slides, you might need to cool the blade in some water and then continue your process.
Once you get your hollow on the grinder, you can follow up with a whetstone, gliding it over the hollow on the front of the blade. Always push, never pull it towards you just as we did earlier on the back.
Other Sharpening Methods
As we mentioned earlier, you can also just sharpen your drawknife using a file or a whetstone, or even both together.
The thing with using these is you are following a completely manual process so it becomes a bit more complicated and time-consuming to get the sharpening completed. If you choose to use these methods, your process will be fairly similar to what we discussed above with the grinder.
The biggest difference will be that you will use the file in place of the grinder for the honing and sharpening process.
Even the best of tools have to be sharpened on occasion. Drawknives are used for hard work so it stands to reason that their blades need to be maintained and sharpened as well. We hope that this guide to sharpening your drawknife makes the process simple for you.
This tool is built to be sturdy and could potentially last forever if you care for it just right!