M42 steel?

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I have some wore out Heavy duty Demolition Reciprocating saw blades, about 12" long. Lennox said they are made from m42 tool steel.
Question is. Is there a way to salvage them to make a useful blade. Hopefully a small wharncliffe style utility.
Thanks in advance for any advice.
 

me2

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You could just grind them into shape as is. If its M42, you can heat it pretty good before worrying about temper effects. Check and see if they are bi-metal. If not, you may have a time shaping them. If so, a wharncliffe style is about all you could expect to make.
 
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Hello! first you will need one of these. and some of these and this. cut out pices of flat rectangles with the hand cut off saw. then draw knives on the flatstock with these. Now use your bench grinder to grind in the profile. dont worry too much about getting it too hot since it's high-speed steel, but use your bear hands, and if you cant hold on to it dunk it in a handy bucket of water. that should be kept near the grinder just for that purpose.
 
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temper is likely between 1000-1100f but you still don't want to burn it up grinding it will were belts but least its thin stock to start with
i did some M42 planer blades but since i annealed then first (computer controlled kiln) i had no problem then doing a re heat treat
 
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Phill Hartsfield made some blades that I bought that were M42 tool steel. I remember him telling me that he grinds it hard and its only suitable for small utility blades.
 

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Thanks for the input everybody. I'm going to go ahead and make some small, mostly wharncliffe style blades from these.
Making sure to grind slow and dunk in water often. For the most part I have to get whats left of the teeth off and make the start of an edge with the grinder. Then hit the edge with the coarse diamond lansky and work down in grit from there.
 
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#3 Yesterday, 08:40 PM
J.S. Carter
Registered User Join Date: Jul 2007
Location: In the land of the Indians
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Hello! first you will need one of these. and some of these and this. cut out pices of flat rectangles with the hand cut off saw. then draw knives on the flatstock with these. Now use your bench grinder to grind in the profile. dont worry too much about getting it too hot since it's high-speed steel, but use your bear hands, and if you cant hold on to it dunk it in a handy bucket of water. that should be kept near the grinder just for that purpose.





thats pretty funny
 
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thanx! thats first hand experiance talkin right there... oddly enough i did do just that yesterday with some M4 or M2 whatever Starrett HSS power hacksaw blades are made out of (red stripes .62" x 1.25" x 14") I had Way too much coffee yesterday, felt like hammie on Over the Hedge, you daddies with yungin's will now what I'm talkin about.
 

me2

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After shaping the blades, post here if you figure out how to drill a hole for handles. I have some M2 that has defied every attempt for handle holes.
 

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I finally made a blade out of one. Phil Hartsfield was right, that stuff is tough to work. I didn't even bother trying to drill a hole. I just used the hole on the end, (were it attaches to the recipro saw), and paracord wrapped the handle.
It took quite a while to put an edge on it with Lansky Diamond stones. It reminded me of reprofiling ZDP.
http://i425.photobucket.com/albums/pp339/jpk222/MyWharny.jpg
 
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