Wednesday, October 4, 2017

Making a SIMPLE knife out of a Sawzall blade




Sometimes you just want to make a quick and dirty knife. Knife making, while being a very rewarding (and fun) hobby, is also very difficult. It requires hard work, determination, and complete and total disregard for personal cleanliness.

It also takes forever.

While I certainly love to put the time and effort into a classic, well polished knife with hardwood handle and immaculate finish; the time comes when I just don't want to do all that work.

This knife can be made in only a couple hours (less if you don't care how it looks) and doesn't require a heat treat.

The secret? It's ground out of a sawzall blade.

Sawzall blades have already been hardened, so as long as I am careful to keep the blade from overheating as I grind, I should be able to forego the heat treatment altogether and still end with a decently hardened blade. In theory at least. We'll see if it's actually true.


At any rate, this is a great method for those of you don't have all the tools, experience, materials, or patience to put together a knife the normal way.





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.)

Anyway.



Step 1: 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 2: Grinding out Shape - Blade profile and Bottom of Tang

Time to start grinding. Often I photocopy the design I drew out, and then trace the outline onto the metal as a guide. In this case I just marked out the basic lines with a sharpie and just eyeballed it. I was feeling low key. 

Pretty basic, not much to explain. Just grinding. 

It is very important that we keep the metal cool. Normally it doesn't really matter if you overheat the steel when grinding, as the knife isn't HT-ed yet and you would be redoing it later. With this knife it's different. We won't be heat treating it later, so if the steel discolors, it's ruined. 

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 3: Grinding out Shape - Shaping Tang 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 4: Grinding 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 5: Drilling Hole in Tang

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 6: Finish 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.

Anyway.

No pictures of it, but I did do a little hand sanding afterward to give it that last little touch up.








Step 7: 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 here, well, bummer. 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 (sharp) the filework 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 8: Forced Patina with Vinegar

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 9: 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.















And....... DONE!!!

Wow, what a simple knife. For only a hour or two of work, I must say that is a very impressive blade.

(no, I am not biased in the least

Whatever.





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 an 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, 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.





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