Lawnmower Blade Machete

S

stvpourciau

Joined
Dec 20, 2012
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I ran a search and found plenty of threads questioning lawnmower blades before but not quite what I'm looking for.

There's plenty of advising against making knives out of these But I'm not looking to make a knife nor do I need A splendid heat treat, I'm just wanting to make simple machete, maybe use it as a cane knife?

The way I figure it should take a beating well and not need to be plenty hard, as long as you can put an edge on it, it should do.

I plan to anneal it, hammer it flat, bevel/grind it, heat it, quench it, throw it in the oven for (???) amount of time and quench it again.

So my question is not can you but have you had success making a "machete"-type knife and roughly what was your HT, roughly what amount of time should these temper for as that seems to be the big problem with these mystery steel blades.

What time/temp did you cook it for and is my plan about right as far as making something that cuts about right or is there some huge flaw in The process that I listed?

Thanks guys, 1st post over in this corner and 1st attempt at making something that cuts, take it easy on The new guy asking about how he should do all the things that he probably shouldn't do, I'm Gunna try it, might as well ask if anyone else has had luck before I just completely wing it.
 
Make sure you eat plenty of french fried potaters while making it. mmmmm

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Planterz said:
Make sure you eat plenty of french fried potaters while making it. mmmmm

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Click to expand...

:thumbup: That's actually way better than serious advice, Billy is one of the coolest/realest guys I've ever had the pleasure of meeting and what's more, I have pictures to prove it! :D

Plus, it was pretty freakin' funny,I'm Gunna get to bed on a good note tonight.

Bravo
 
For the price and amount of work involved, use some 1084 from Aldo. The raw steel will cost you less than a new mower blade, and you can heat treat it with a very basic setup.
 
Try it, get some old worn out mower props from a lawn and garden outfit, they usually have plenty and experiment. The steel is tough to prevent shattering for safety when they strike things like rocks and cement curbs, they may make good machetes. You won't know until you try.
 
My best friend's dad made a hell of a knife out of an old lawn mower blade. He used a shop grinder to profile it, then a bonfire to "treat" it. In sticking with his backyard ways, he then sharpened it with a set of files. The burr could remove skin when I dragged it spine first first across my arm.

BUT, it weighed a metric ton, and could hack through small saplings like they were made of styrofoam. Makes me wonder what would happen if I could put a proper edge on it...

I don't think you can ever go wrong with attempting to making your own knife out of anything. The important part is to have fun learning!
 
Lawnmower blade steel is not suitable for a machete. Mowers cut by moving the blade at an incredibly high speed. They don't even have to be sharp. These blades are too soft for machetes.
Get the proper steel (1084 is great). It's inexpensive and it works.
Forget the "bonfire" hardening. All the information you need is available right here to do it properly.
 
Several years back I needed to de-bark some lodge poles, and forged a draw knife out of an edger blade. There are obvious advantages to using a well understood tool steel, but sometimes I enjoy the challenge of making something that does the job, without having to buy anything. It's been a while, but I think I heated to non-magnetic and quenched in oil, maybe a couple of times. Then to draw out the temper, I sanded it to bright metal, then turned off the forge and laid it on the hot firebrick floor until the cutting edge got hot enough to turn straw yellow (400ish), and water quenched. It held an edge even after plowing through quite a few pine knots.
 
JamesBrauer said:
Several years back I needed to de-bark some lodge poles, and forged a draw knife out of an edger blade. There are obvious advantages to using a well understood tool steel, but sometimes I enjoy the challenge of making something that does the job, without having to buy anything. It's been a while, but I think I heated to non-magnetic and quenched in oil, maybe a couple of times. Then to draw out the temper, I sanded it to bright metal, then turned off the forge and laid it on the hot firebrick floor until the cutting edge got hot enough to turn straw yellow (400ish), and water quenched. It held an edge even after plowing through quite a few pine knots.
Click to expand...

:thumbup:
 
....and still, everyone's an expert.
My bet is that none of you have any idea what a real knife is like.
 
To quote another classic film, "Some men, you just cain't reach."
 
You can always tell the newbies-you just can't tell them anything!
 
A lot of the new lawn mower blades are low carbon boron steel. Make up a brine solution by adding @ 15 pounds of rock salt to 5 gallons of water place in a metal container. Throw in some jet dry. This is your quenching solution. Anneal your blade. Heat up about 4 inches of the end of your blade to orange yellow and hold for a couple of minutes. Quench while moving the blade around. Place @ 2" of the quenched end over the edge of your anvil. Make sure you are wearing eye and clothing protection and everyone else is too. gently pound on the end of the blade and try to bend it over the edge of the anvil. If it doesn't break hit it increasingly harder. If it bends without breaking you do not need to worry about a temper. take a file and test the rest of the blade to see how easy it files. Now test the quenched end. If they cut about the same you probably don't need to quench. Let us know how it turns out.
 
I don't have any lawn mowerr blades. Can I use a piece of Aldo's cheap 1084 to make a machete instead???
 
BoT
The ratio for brine is 8-10%, that is about 3-4 pounds in five gallons. 15 pounds per 5 gallons might not even dissolve.

For those new to all this, brine is the fastest quenchant that we have safely available.10% Sodium hydroxide quenchant is only a tiny bit faster. Water is half the speed of brine, and fast oil is half the speed of water. Air is .015 the speed of water. You pick the proper quenchant for the rate of cooling needed for the steel you will use. Faster cooling does not mean harder blades or the ability to make non-hardening steels get hard.
 
SteelSlaver:
While mattress frames and lawn mower blades are just about the best steel ( second only to anything found in an old garage), if you have nothing else to use, Aldo's 1084 will work.
 
A little off topic, but related to the replies received herein...

In the small town where I live peddlers need to have a license to solicit door to door. It occurred to me that we ought to have licenses on Blade Forums for distributing bad advice or sarcarstic advice. Only valid license holders would be authorized to reply to threads like this.

- Greg
 
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