Restoring an Antique Drawknife
by antagonizer in Workshop > Tools
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Restoring an Antique Drawknife
This project uses, what I call, the trinity of my craft; wood, metal and leather, that all come together to create a piece that can be both a precision woodworking instrument, as well as a course tool that can make short work of any large project.
For me, tool making represents the pinnacle of what it means to be human. Keeping these tools in in good working order means a regiment of maintenance that can, often, get overlooked as time wears on. As a lover of traditional woodworking, many of my tools are restored vintage and antique pieces that often need a bit of 'love' to become functional again, which can mean a complete restoration.
Now, I've seen a few drawknife restorations online, and found them to be somewhat lacking, in that many end up aesthetically appealing, but functionally imperfect. It's easy to treat a handle replacement the same way as you would...say...a knife handle, however when you consider that the pressures applied are in a horizontal 'pull' direction and not in a vertical 'chop' motion, as a knife would be, you soon realize the importance of altering the construction method. When restoring a piece, It's important to remember that strength and integrity shouldn't be sacrificed for beauty and form.
Like many of my tools, this drawknife has been in my family for generations. I inherited it from my father who, in turn, inherited it from my grandfather. Over the years, it's seen a lot of use and abuse and is in need of a complete overhaul.
Tools and Supplies
Tools;
- Wood Lathe
- Bench Grinder with wire wheel and emery wheel
- Belt Grinder
- Table Saw
- Leathercraft Tools
- Propane Torch
- Wooden Mallet
- Ball Peen Hammer
- Drill press and bits
- Coping Saw
Supplies;
- Vintage Drawknife
- 1.25"x1.25"x8" block of hardwood
- 1"x1" brass or stainless steel tubing
- 1.5"x8" strip of 2-3oz leather
- 2 1/8" x 12" leather thongs
- Leather conditioner (my instructable on high grade beeswax polish) Leather dye optional
- Used motor oil or chain lube
- sandpaper 150-800 grit
- 5 minute epoxy
Prepping the Blade
After years of wear and tear, cleaning up the blade will mean more than just a re-handle and a polish. Things like dents, dings, and flattened marks from impacts can all affect the performance of the tool, and need to be fixed. Before any of that takes place, you'll need to remove the handles.
I'd suggest that you don't bother trying to carefully remove the handles as they're probably far too rotten and damaged to save. Not to mention, the ends of the tangs are likely 'clinched' (as in the first image), which wold mean straightening them first. I found a couple antique barn nails hidden in my handle, likely put there years ago to arrest any play that may have formed over the years. Don't worry about straightening the clinched ends as they have likely become brittle over the years and would probably break before bending. I'd recommend cutting them off and shortening the length of your handle slightly, which shouldn't impact the function of your drawknife.
When restoring the blade, it can be tempting to just start grinding the entire surface down and starting from scratch. This is fine if you have plenty of material to work with, and aren't concerned as much about 'refurbishing' as opposed to 'restoration'. Restoration means only removing as much material as is necessary, and trying to retain as much of the 'age' as possible, without sacrificing function.
As mentioned, I recommend only grinding down any dents and chips, on your belt grinder as necessary, straightening the edge and the spine. You can bevel the edge, but don't sharpen your drawknife just yet. This will make it easier to work with, without having to worry about cutting yourself in the process.
**Note** Remember, the bevel edge is only on one side of the drawknife and the other is perfectly flat.
Refining the Blade
As mentioned before, there are two ways you can approach this; refurbishing and restoration. Refurbishing means that you attempt to remove all traces of age and try to bring the piece back to the condition it was when it was first crafted while restoration means attempting to retain some of the elements of age, allowing them to enhance the look of the piece. Personally, I prefer restoration over refurbishing, but in the end, the choice is yours.
In order to retain as much of the age as possible, I tried to keep some of the elements, such as the patina and pitting of the steel, without compromising its integrity. That didn't mean I didn't sand the piece down. Rather I used much gentler equipment such as the wire and emery wheel which only removed the course grinding marks from the last step, and the rust. Once I was satisfied, I moved straight to 220/400/600/800 grit paper, gradually wet sanding to give a smooth surface the didn't show tool marks.
The Patina
Once the surface is smooth and even, It's good to replace some of the patina that was lost during the process. A little trick I use is to spray chain lube, or old motor oil all over the blade, then use a torch to burn it so that it leaves a residue and darkens the steel. This will help prevent further rust and staining on the blade and works much the same way as gun blue does on a firearm.
Finally, You'll need to anneal the tips of the tangs so that they can be re-clinched. You can do this with the handles installed, but I recommend doing it before hand so that you don't burn the handle.
**Note on the emery wheel** The emery wheel is a wheel that fits on a standard bench grinder, but is different that is is a spongy material, rather than a solid stone material. It is far less abrasive and acts more as a sandpaper than a grinder.
Turning the Handles
You can turn the handles independently, but it's far easier to turn them together, from one piece of wood, as it'll make it easier to ensure they are symmetrical.
Once you piece is rounded, use your parting tool to divide it into two equal sections. The overall length of the sections should be 1/2" shorter than the length of the tangs on your blade. Mine ended up being 4". When you have the two sections measured out, you'll need to create the bevel for the lock ring. The rings are cut out of 1" stainless steel tube stock with an inside diameter of .919" and 1" long. I cut the bevel to 1" and a diameter of .935", just slightly larger than the i.d. of the tube. The reason for this will be clear in the installation step.
When creating your handles, turning them into a 'pear' shape will afford something to hold on to as you draw the knife, tho you can use some creativity in the final design. I'd recommend cutting some scores at regular intervals on the handles as they'll go a long way to adding grip. Again, it's a matter of choice but they do work well.
Finally, sand down you work using progressively finer grit paper, and finish by wet sanding. You can finish your work with some lacquer, but I like to use a high quality beeswax polish of my own design. You can find a link to my instructable in the tools and supplies section of this instructable.
The Handle Lock Rings
Many of the refurbs I've seen done, online, treat these as decorative, but their function goes far beyond that. Primarily, their purpose was to prevent splitting of the wood, but as a secondary function, they lock the handle in place, preventing movement as wear and tear acts on the tool. You can create the handles without them, however I strongly recommend that you incorporate them.
Cut the rings 1" long and sand the ends to remove burrs. I recycled some old stainless pipe I had laying around, so they needed a bit of buffing on the wire wheel to clean them up. Once they are cleaned up, set them aside for the next step.
Sharpening The Blade
Once the handle is secure, you can sharpen your blade using your favorite method. For me, I prefer to use my belt grinder with a 220 grit belt installed, then using 400 stone to finish. I generally don't go much higher than that, as a drawknife doesn't need a finely honed edge like a knife does. More often than not, if you hone to 'shaving' sharpness, the edge will wear within the first 5 minutes of use, making it pointless. You can, however graduate to a 2000 grit stone and strop if you choose.
Prepping the Handles
It's very likely that the tang on your drawknife is tapered, which means you'll need to drill the handle from both ends to accommodate that. They will need to be exactly the size of the tang, as making them too large will cause your handle to become loose.
Lock your handle in a clamp, to ensure a straight hole, and start by drilling the smallest diameter first, going all the way through the handle. Then, flip you handle over and drill out the opposite side half way. This will prevent the handle from being over sized and potentially becoming loose.
Finally, using your coping saw, cut a slot in the bevel that is 1/16" wide. As the ring is tapped over the bevel, it will compress it holding it much firmer than simply being press fit alone.
Installing the Handles
Installation is very easy, but needs to be done in steps. Apply some 5 minute epoxy to the tang, and to the inside of the handle. This will fill any gaps between the handle and tang, ensuring it never moves. Then, place the ring around the tang, then slide the handle over until it stops. Don't hammer it on yet. Next, place the ring over the bevel, tapping it down 1/4 of the way. You don't need to glue it if your bevel was measured properly. Begin tapping down the handle, setting it into position. To avoid damaging the handle, I recommend using a large washer and a socket to set it. Finally, you can tap the lock ring into place.
Clinching The Tang Ends
This is the most important step, and is used to stop the handle from sliding off when the drawknife is being used. A human being can pull, upwards, of 2000N, which is just under 450lbs which represents a huge force on wooden handles. If they aren't attached properly, this could end up being a hazard on the user.
To clinch the tang end, you'll need to apply some heat to the tip, then hammer it over using your ball peen hammer. As we've already annealed them, this should be a pretty simple process, however you'll need to quench immediately so as not to burn your wood or melt your glue. I recommend only applying heat to the tip, as it will prevent the hot metal from torching the handle. Keep a spray bottle nearby as this will make the cooling process easier.
The Leather Blade Guard
Cut your 8"x1.5" strip of leather and wet it thoroughly. Punch two holes at each end to allow the thong to pass through, then fold it in half, allowing it to dry in that shape.
Next, thread your thong through the holes, downward so that the ends are on the folded side of the strip, and not the open side. Allow it to fully dry then apply some leather conditioner or polish. You can find a link to my high grade beeswax polish in the tools and supplies section of this instructable.
The blade guard works by looping the thongs over the spine of the blade, with the guard on its edge. As the thongs are drawn tight, it will pull the entire guard into place. You can leave the thongs loose, as I did, or you can tie them so that they hold the guard securely.
Finished
That's it, you're done.
Restoring old tools can be very rewarding making them heirlooms that can be passed on to your children for generations to come.
As usual, I hope you enjoyed the instructable and thanks for following.