Sawzall Blades?

G

GarageBoy

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May 23, 2003
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I was wondering what High Speed Steel Sawzall blades are made from and is it knife quality? They seem durable enough(They can saw through steel and iron)
 
High speed steel usually means M2. They are commonly used for small knives, left at full hardness.

-Cliff
 
Sawzall is a trademarked name from Milwaukee.
Super Sawzall blades are made with Matrix II high speed steel teeth containing 8 percent Cobalt to keep a sharper tooth edge longer. The tough Bi-Metal design allows faster cutting, longer life blades that can bend without shattering.
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I noticed that Lenox also seems to use a Cobalt based alloy. Dewalt probably does too.

Bi-metal just means that the back of the blade is a tough, flexible, cheap material (probably just carbon steel). The teeth are what are made from the high speed steel (more expensive). I read somewhere that they have a pretty clever way of heat treating the teeth... seems like it's a laser that zaps the high speed steel and gets it up to austenizing temperature quickly, then they quench somehow. Since the teeth are small, the laser can get enough energy into the teeth to heat them up pretty quickly. (the laser part might not be correct, it could be some kind of induction heating, but I'm too tired to research on the web now).

The term "High speed" comes from the fact that the alloy's typically have a high alloy content with tungsten, chromium and molybdenum usually being key elements that provide for steel (the teeth) hardness retention even at high temperatures (and indeed, Cobalt might provide red hardness also). "High speed" probably comes from the machine tool arena, i.e. you can turn a tool bit at high speeds, get it hot, and it has "red hardness"... retains hardness at red hot temperatures. Tool doesn't de-temper.

So for metal cutting or demolition blades in a reciprocating saw (Sawzall), you can really get the blade hot in metal and/or wood, and you won't temper the hardness of the teeth down from the heat.

One vendor quoted the following:
Two types of high speed steel edges:

Matrix II: Heat treated to Rc 65-68
Mainly used in mild or medium hard materials. The lower Rc level makes the blade more forgiving against tooth fracture.
M-42: Heat treated to Rc 66-69
Mainly used in medium to hard materials
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M-42 is a somewhat higher alloy material than M-2.

Crucible's web site has more on the "M" series steels ... their makeup, typical hardnesses, uses, etc.

M series tool steels can make fine knife blades... but the M series of high speed steels is apparently very demanding to heat treat, requiring precise austenizing temperatures, short soak times, and perhaps special quenching techniques to extract the performance. Even the better custom makers tend to send the M steels out for professional (read "industrial") heat treat.

Benchmade is one of the few who offer blades in M2. The two folders I use for hard work around the house/yard are Benchmades, a 710 and an 800 AFCK in M2.
 
Nice write-up Rob. Good piece of research. That reminds me. I have a new (powerful) Sawzall and I need to cut-up something. Very satisfying. :D
 
I just bought a Milwaukee Sawzall this year. Renovating a house, and it's a mandatory tool for renovation. Makes me wonder how I ever got along without one. That, and a sliding miter saw, and a good circular saw, good jigsaw, drill press, and a ... etc.

The Milwaukee's are nice as they have a patented counterbalancing mechanism that allows them to vibrate less than the other brands.

A crew just installed new windows in my house, and I picked up one of the guy's Porter Cable Tiger Saws (a good durable make) and it did vibrate noticably more.

Great tools. Brings out the Tim Taylor in me... ;)
 
One snippet I found:
What that means is that a high carbon steel back is used for strength and then a tungsten steel cutting edge is ultrasonically welded to the blade.
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Bimetal approach is used for a variety of blades, including hacksaws, industrial hacksaw machines, bandsaws for wood and metal, and of course Sawzall metal and demolition blades... many others I'm sure.
 
Idaho Knife works makes the cliff Canoe Knife from L6 (bandsaw blades?) Fantastic knife for food prep.
 
Originally posted by rdangerer
A crew just installed new windows in my house, and I picked up one of the guy's Porter Cable Tiger Saws (a good durable make) and it did vibrate noticably more.
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I have the PC Tiger saw. It does vibrate a good bit.

These types of saws are great, aren't they? With the right blade, I can eliminate a handheld circular saw, jig saw (for large jobs), chainsaw (for small jobs, I remove branches, small trees,and several bushes with mine), and a regular handsaw.

Chris
 
I have no real need for a sawzall but Milwaukee has a cordless model with a folding handle. Does this qualify as a 'folder'?

Cheers,
Collector
 
My .02 cents~~~ I have a DeWalt and my buddies Milwaukee vibrates a bit less than it does. It has held up well after a number of years now though.
 
I don't know about all of them, but the Milwaukee Orbital Super Sawzall has a counterweight in the mechanism to keep vibration down (you'll have to ask someone else how/why it works).
Thanks, Rob, for the info on the blades. I was always curious.

btw, if you haven't used a Sawzall with orbital action, I can tell you it makes a HUGE difference in cutting ability on both wood and steel.
 
Originally posted by OwenM
... Sawzall with orbital action, I can tell you it makes a HUGE difference in cutting ability on both wood and steel.
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The orbital action also works wonders in jigsaws. I was cutting some 3/4" plywood with a new Metabo jigsaw (good German brand), and I was kinda leaning on it to get it to cut even with a brand new aggressive wood cutting blade. Then I flipped on full orbital motion, and the thing just started motoring right through the 3/4" plywood almost without any force applied. An impressive demo of how well orbital action works when you can surrender a bit of precision for brute speed and ease.

(sidebard: the Metabo STE 105 plus is a real gem... better even than the Bosch all around BEFORE the addition of a quick-change blade mechanism. Only downside for Metabo, other than price: will be harder to get it repaired in the US than with a US vendor or with Bosch... they just don't have the presence yet)

http://www.metabo.com/com/english/produkte/katalog/jig_saws/6_10500_50_ste_105_plus.htm
 
One other blip from an interesting web page:

Co ( Cobalt )
· Like Cu, a Ferrite "stiffener" ( by means of solid solution strengthening ), an effect that persists at high tempertures ( i.e., increases hot hardness ).
· Like Ni, cannot remove Co from molten steel.
· VERY EXPENSIVE

W ( Tungsten )
· Forms extremely hard, stable carbides. Used almost exclusively in High Speed and other tool steels (requiring wear resistance and high hot hardness).
· VERY EXPENSIVE Used in the manufacture of “High Speed Tool Steel”, but otherwise almost never used due to extremely high cost.
Click to expand...

Excerpted from http://www.steelnet.org/new/20030210.a.htm
 
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