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I have a 7-1/4inch worm drive saw (Craftsman)...  Is it possible to use this saw for cutting steel with the proper blade?
Reply:Sure it'll work.  The biggest problem is that the molten metal sparks will pit the plastic case (anything they hit that's not metal).  They're hot enough that they'll stick in the plastic and make the surface like sandpaper.  If it's made by Milwaukee or Bosch (Sears carries both) it not so much of a problem - the polymer they use for handles is much more resistent.  I'd tape a piece of thin sheet steel or something between the motor ventilation vents and the blade to prevent sparks from getting into the electric motor.  I did this with an inexpensive B&D radial hand saw but probably wouldn't with my worm-drive HD77M Skilsaw (cost about 8 times the B&D).
Reply:There's usually one heck of an RPM difference between the saws designed for wood and those dry cuts designed for metals. About 4X..
Reply:You can run an abrasive blade on it, but I wouldn't.  I ran an abrasive blade on my 14" Makita miter saw and melted some of the plastic parts.  It also spun too slow for the abrasive blade and cut very slow.  It spins too fast for a metal cutting carbide blade too, you'll wreck the blade.  I use the Makita to cut aluminum, it works good for that, and of course wood.  No more steel cutting with it.If you want to cut steel with a carbide blade on a 7.25" circular saw, they make some specificaly for that purpose.  I believe Evolution has one, as well as the other well-known company that makes 14" cold cut chop saws, which I forget the name of at the moment.   They're expensive, but better than wrecking a good framing saw with an abrasive blade or wasting expensive cold blades spinning them too fast.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Problem with using any circular saw for this is that its not geared and made to handle the torque required or the hot sparks.Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:a sawzall would probably work better
Reply:Now, after all that has been said, I have one that has been used almost exclusively for steel for close to a dozen years, and its just fine,,,,Its a Skil saw......
Reply:There are blades out there designed specifically for the RPM of these saws.  If you make SURE you get the correctly rated blade, give it a go.  I had a carbide steel-cutting one on a Milwaukee circular saw and it worked great.  The blades aren't cheap, but they work well.The abrasive blades also work, but since these saws are invariably too slow, they work slowly and throw lots of sparks into places where they might mar the finish of the saw.  I used many of these blades in a worm-drive DeWalt for mobile work.
Reply:Bill,Short answer - Yes you can do it.Longer answer - Yes you can do it with the appropriate blade.  Lowes and HomeDepot both usually have a 7-1/4 blade made for a 5000 rpm saw to cut steel.  Freud and Lenox are the brands that the I've seen in the box stores.  IIRC, they are about $40-$50 or so per blade.  You can also get blades on-line, Freud or Lenox or MetalDevil, etc.Within the blade's limits (rpm, material thickness of 1/8 inch MAX, plain mild steel not hardplate or such, etc), the cut is darn good IMHO and loads better and easier than using an abrasive blade in the circular saw.  Not quite as easy as a hot knife through butter, but relatively quick and easy for getting through some thin 1/8 inch plate steel.  The cut is LOUD and there are metal chips all over the place, but the blade worked pretty well for me.But a plasma cutter is faster and easier and you can cut curves.    The best laid schemes ... Gang oft agley ...
Reply:I have cut both alum and mild steel sheet less than 1/8" with those blades specifically designed to run in circular saws. I strictly use wormdrives for this (and concrete). I keep my eye out for used wormdrives. The last one I snagged for $50 at the used tool store. Looked like crap but I use it to cut concrete floors or cement board and the dust will eventually ruin the saw anyways.Be careful there is a LOT of torque on those saws and they WILL take off in unexpected directions if you bind the blade. I always use both hands on those saws cutting steel and alum, compared to frequently cutting one handed with then in wood.Be safe and good luck.
Reply:Don't regularly use a circ saw for metal, but if it's really thin sheet metal(like Pro Panel roofing), just turn an old crosscut wood blade around,  and cut.  Makes one hell of a lot of noise, but it works."Any day above ground is a good day"http://www.farmersamm.com/
Reply:I know the worm saw runs at a much lower RPM's then a direct drive.  This is going to be a factor in selecting the right blade.   So off I will go and see if I can find a suitable blade.  I promise to report back with some test results.
Reply:I misstated the plate thickness capability of a carbide-tipped ferrous-cutting 7-1/4 inch Freud blade.It's 1/4 inch MAX plain mild steel.  HomeDepot, about $40.http://www.homedepot.com/webapp/wcs/...425+4294919487See also a Dewalt ferrous-cutting 7-1/4 inch blade at http://www.dewalt.com/us/products/ac...ategoryID=4116And others as I previously wrote.  I have used the Freud, a borrowed (dull) MetalDevil, and have seen the Lenox version.  And a blade rated as 5800 rpm max (typical 'regular' 7-1/4 inch saw rpm) is fine to use in a worm-drive 7-1/4 inch saw (typical rpm of a worm-drive 7-1/4 is ~4600 rpm).And the two different saw types are right-angle drive (the motor shaft is parallel to the blade arbor) or worm-drive (motor shaft is in-line with the saw handle/body and actually at a right-angle to the blade arbor).  Both saws use gears and neither is typically 'direct-drive'.Last edited by MoonRise; 02-10-2009 at 04:37 PM.  The best laid schemes ... Gang oft agley ...
Reply:Thanks for the saw blade info... I don't plan on cutting anything thicker than 1/8".    Plasma and or O/A is my next option.  Ka Ching...
Reply:I've seen blades that will cut up to 1/4+ steel with no problems with a standard circular saw, I will have to try to remember the brands.  They were expensive at over $100, though.
Reply:What and how much are you trying or wanting or needing to cut?Is this just a "I need a tool to be able to cut steel plate in case I want to" or is there a specific application you are trying to do?  The best laid schemes ... Gang oft agley ...
Reply:This is sort of a nice to have option for cutting thin steel plate… I have this saw that rarely gets used; so I figured what the heck, let’s put that puppy to work.   I may re-think this if cutting metal is going to destroy the saw.
Reply:Home Depot and the $40 Freud blade.  Done.  The best laid schemes ... Gang oft agley ...
Reply:A couple of cuts won't kill that saw. I get dozens of hours of cutting concrete and cement board with one. The saw sucks in all that abrasive dust and still runs on and on. And that's usually after hundreds of hours cutting framing lumber. In truth I have only had one wormdrive die cutting concrete in all the years I have used them. That saw still cut and ran, but spit out tons of sparks from the brushes as it ran and made a terrible noise. It's not a one use and the saw is crap type of thing.
Reply:I have an older sears circular saw that i use for metal sometimes. Harbor freight sells 8 inch abrasive blades that fit it. Its good to use for a quick cut and a long straight cut. Just clamp a straight edge and go!!Ya gotta spend money to make money!