This Instructable details my process of making a simple knife out of a sawzall blade. (Stock removal method, logically.)
Sawzall blades are already heat treated, so if we are careful not to overheat the steel while grinding out the blade, theoretically we should be able to bypass the heat treating process altogether and still end up with a hardened blade. I put theoretically in scary bold and italics because well, we'll see if it ends up being true. (more on that at the end)
This project started when my Dad broke one of his large sawzall blades at a job (a common occurrence). Being always on the lookout for scraps of metal with which to make stuff, I snapped it up.
Wait a minute. Actually, that's not quite how it happened. First he gave to my one of my little brothers, who was going to make a knife out of it, and he had it for several months. (They can be a bit slow with the making thing) Then another of my brothers picked up some old chewed up deer antler from a friend. (I have a lot of brothers. And the deer antler has nothing to do with this project.) I traded an obsidian arrowhead (from my rock collection) for the deer antler, which I traded to the other one (brother) for the sawzall blade. (No worries, I then traded a bag of pennies and a prop Lord of the Rings one ring to get the antler back. I'll use that for another project.)
I got an old sawzall blade.
And I'm going to make a knife out of it.
Step 1: Video
Step 2: Design
I find that nearly all of my projects begin with me sitting at my desk, staring down at a blank sheet of notebook paper, with a pencil in my hand, good music playing, and a large cup of strong coffee on my desk.
Ok, fine; most days life gets the best of me. But that's how I like to do it. I find planning my projects out on paper to be an inestimably valuable as well as just plain fun part of the creating process.
(I'd check out this class if I were you. Highly recomended and very helpfull. I learned some great tricks: https://www.instructables.com/class/Design-Sketching-Class/)
This was no exception. I traced the shape of the sawblade onto the paper, and then sketched out the knife I saw in it. It turned out to be a japanese inspired tactical knife with a slightly upswept tanto blade, jimping on the spine, and a sweet paracord handle wrap to add that nice, minimalistic-yet-totally-cool-look.
Step 3: Grinding Teeth Off, Shaping Spine and Bottom of Handle
We are turning a sawblade into a knife. A sawblade has teeth. A knife doesn't.
So grind them off.
The handle needs shaped too, so -
Don't know about you, but I have trouble writing about self explanatory things. It seems redundant. No, worse than that. Almost hypocritical. Forces people to be less observant. More dumb. Less smart.
Not only have l gone to all the trouble of taking and uploading way too many pictures (my ibles are always pic-heavy), but now I'm 'sposed to write a detailed description. Telling you what the pictures and title already state with crystal clarity.
Sorry, I don't support stupidity.
All the info you need is in the pics and step description.
Step 4: Grinding Blade Profile
Here I grind out the shape of the blade. It is very important in this step that we keep the metal cool. If you overheat the steel on the handle or on any spot not going to be cutting edge it doesn't really matter, but if you mess up the heat treat on the blade it won't hold an edge later.
Remember, we aren't going to be heat treating this knife. If the steel discolors, you have ruined the HT. I advise you grind with bare hands, so you can feel the temperature of the metal. When it gets hot to touch, dunk it in water.
Step 5: Grinding Sides of Handle (for Paracord Wrap)
Most handle wraps look like an afterthought. Like someone just slapped some paracord around a tang designed for something else. I wanted mine to look like it was meant to be there.
A lot of that depends on the particular wrap you do (sorry, but most of them look like absolute CRUD), but it also helps if you design the knife with a handle wrap in mind. To help it fit in with the rest of the knife, I ground the handle down a good 1/8th of an inch on both sides where I was planning for the paracord to go. (hard to explain, see pictures)
It will help the paracord stay in place on the handle, as well as make it look like the wrap is built into the tang.
Step 6: Refining Grinds, Sanding
After I finish roughing out the shape with my bench grinder, I move over the belt sanders and clean up everything.
Professional knifemakers generally don't use bench grinders; they do all their grinding on their fancy-shmancy high powered 2x72 belt sanders (you can tell I'm jealous). Then they just switch belts to do the finer sanding.
I don't own a high powered belt grinder. Thus, when I need to take off material quickly, I find it best to use my bench grinder, and move to my underpowered sanders mainly for grinding bevels, finish sanding, and shaping wood for handles.
Not that you couldn't do all do the main grinding on the sanders, but I find it takes much longer. That's just wearing the belts out unnecessarily.
No pictures of it, but I did do a little hand sanding afterward to give it that last little touch up.
Step 7: Grind Edge Bevels
Here's another step that is fairly self explanatory. As before, just be careful to keep the metal cool.
A lot of knife makers use jigs to help them get even grinds. I don't. (Haven't made one yet)
Mainly it just takes patience and a steady hand.
Step 8: Drill Hole Handle (for Handle Wrap)
The traditional japanese knife handle wrap requires the presence of a hole in the bottom of the tang. The japanese inspired wrap I will be doing will require a hole as well.
So I drilled one.
Since we are dealing with hardened steel, keep in mind that it will be very tough to drill through. As of yet I do not own any good metal eating drill bits, so I had to go slow and step up with progressively larger bits until the hole was the size I wanted. I believe it ended up being a quarter inch in diameter.
Tip: If you are feeling really impatient, you could anneal that portion of the tang with a blowtorch. It will then be much softer and easier to drill through.
Step 9: Jimping
Good filework requires more practice than anything else. If you are hoping to get some great tips and techniques for how to file good jimping in this step, well, you're going to be disappointed. I can count the number of knives on which I've done fancy filework on one hand, so I hardly feel that I should be telling you what to do.
The main thing I've learned is to go slow and pay careful attention to spacing. Well done jimping can add that extra bit to set the knife apart, but bad filework sticks out like a sore thumb.
I would also be careful with how aggressive the jimping is. Good jimping fits your hand comfortably, adding just the perfect amount of extra grip. It should NOT bite into your thumb. I can't stand it when jimping gets uncomfortable after a few minutes of use. It completely destroys the purpose.
Step 10: Vinegar Patina
At this point the knife was looking good, but was a bit too shiny. Pretty. Clean looking.
It just wasn't giving me that tactical vibe I was looking for.
So I decided to darken the steel. A few hours in a vinegar bath and we were back in business.
Step 11: Handle Wrap
This handle wrap is about as simple as it gets.
Over, under, over, under. Run through the hole. Tie a knot.
^ that's my explanation. Sorry.
If I were to write more I'd only confuse you. The pictures make it more clear than any amount of description.
If you are still stuck, the video will clear it up.
Step 12: Done!!
Wow, what a simple knife. For only a hour or two of work, I must say that is a very impressive blade. (I am completely unbiased)
So.........do sawzall blades make decent knives? Is the steel hard enough?
In my experience, they are ok. Not amazing. The steel is not quite as hard as your average knife. I'm guessing they HT these things with shock resistance in mind, not edge retention. If you've ever seen a sawzall in action, you know the blades have to hold up under incredible amount of vibration and shock, something a blade hardened for pure edge holding couldn't stand. So the steel is a bit softer than preferable on a knife. Which just means you will have to sharpen it more often.
Is it the knife i'm going to take on that backpacking trip to the Rockies?(which, btw, I am not taking) No. But seriously, you made it in a couple hours out of trash. Still cool in my book.
I am entering this instructable in the Reclaimed Contest, so vote if you want me to get a free t-shirt.
And if you liked the instructable.
Hope you learned something today and see you next time,
Third Prize in the
Reclaimed Contest 2017