Cutting Steel with Circular saw

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I am going to get some 1/8 or 1/4 in thick mild steel plate 4'x8' sheets and was needing to cut it.  No money for a plasma and no access to an O/A torch.  I found on the web the Metal Devil circular saw blade by Morse that claims it will saw up to 1/4 inch mild steel sheet.At $40-$50 this is pretty cheap compared to a plasma and maybe much neater as well.  For a limited number of cuts it seems like a cheap solution.  Do these metal cutting circular saw blades really work?  Anyone here ever use these?
Reply:They work excellent. I've got a 9" evolution and regularly cut up to half inch with it. Its rated for 3/8" though. That price is just for the blades though. You're not supposed to use them on a regular circular saw. The blade speed is to fast for metal cutting.
Reply:Hey WelderDaddy, That’s going to be a futile job with a circular saw. The metal cutting blades are designed to be turned at lower speed. Maybe a slicing wheel in a 4” grinder? But probably a sawsall is the answer. Plenty of used ones around at the pawnshop and flea market, cheap. Buy a usa major brand, high amp, with a cord, it’s a versatile tool that you’ll have forever. If you see one engraved “denrep” it’s good, just stolen!
Reply:If your needing any amount of full length or full width cut (the 4' or 8' way), You might want to see what the steel shop would charge to just do the main cuts for ya. Not that I want to discourage doing it yourself but with out a decent set up these types of cuts can be pretty intense  . Of course on the other hand, doing it yourself is great for the learning curve. Everyone has their own preferences and hands on is the best way of figuring out what you need and prefer. Good luck. Let us know how it all works out.
Reply:I saw a blade at a demonstration that could be used in a standard circular saw and cut 1/4" steel.  I wish I could remember who made it.
Reply:well im not gonna tell  ya to, but I have used a chop blade on a no name 7.25 circular saw.  It was clumsy, fence caught on metal in wierd and dangerous ways, unprecise, but it worked.RPM is a wee bit high for the cut off blades as well.
Reply:I've also used an abrasive blade on a regular skill saw.  It worked but make sure you take proper safety precautions!  I was expecting everything to fly apart at any moment.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:I got one of these from Harbor Freight -- works great if not used commercially like all Harbor Freight stuff.  I've cut up to 3/16" with no problem.I got mine on sale for $60 with coupon.http://www.harborfreight.com/cpi/cta...emnumber=94362
Reply:The one I mentioned wasn't an abrasive blade, it was a toothed blade with carbide tips.
Reply:I believe I've seen circular saws at TSC for metal, fairly cheap.  I believe they Clarke brand.  I have several Clarke items and never had any trouble with them, I don't have one of those though.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:Seems familiar... Wasn't there a three stooges episode about this where Larry did something like this and got metal shards stuck into his forehead?
Reply:Just a mention of the three stooges makes me laugh. I have the image in my head of the precious chinese jewelry chest, or whatever it was, going through the saw and getting sliced in two. Or Moe telling Larry that the nail was for the opposite wall when Larry was confused because he had the head facing the wall... Great stuff
Reply:For 1/8 inch thick plate and straight cuts, the appropriate carbide-tipped ferrous metal-cutting blade(s) work great.  Like this Freud blade, about $40 at HomeDepot  http://www.freudtools.com/contractor...6_D0748F_A.jpgMuch faster, easier, and better cut than using an abrasive wheel in the saw.  Not as fast or as easy as using a plasma though.For any curves or shapes, you'd need a plasma, O/A cutting torch, or a reciprocating saw with the appropriate metal-cutting blades (Lenox makes some good ones).  Or a metal-cutting vertical bandsaw.  Or a wire-EDM machine, or a waterjet, or a CNC laser, etc, etc.Whatever blade you get, double check the RPM rating before buying or using it.  Some of the carbide-tipped metal-cutting blades are made for slower RPM saws, and some can be used in a typical 7 1/4 inch circular saw.If you are going to use a blade like the Freud or MetalDevil, and you're just going to stick it into your home-use circular saw, make sure the saw has enough amps/ooomph/snot and that it has a metal blade-guard and not a plastic one.  I don't know what kind of saw you might have, so just figured I'd give you a heads-up.  If you have a 15 amp 7 1/4 inch saw with a metal blade guard, you're good to go with the appropriate blade.Cutting 1/4 inch plate with that Freud might be a bit much though.  There is a biiiig difference between cutting 1/8 plate or thinner and trying to get through 1/4 inch plate with a carbide saw.  Plasma or O/A torch really doesn't notice the thickness difference, but pushing that saw you can sure notice a difference!
Reply:I agree with Denrep about the sawsall.  A sabre saw also works well with a high speed steel blade.  Kinda slow and you need plenty of oil but also accurate in following a line.
Reply:You need to be careful using the abrasive blades on the circular saws (especially on thick stuff) the heat that is generated will smoke the saw.....I have personal experience.  Absolutely fried the dam thing not too mention the amount of build-up of molten steel that deposited itself on the blade guard. I think you would be off with a standard air cutoff tool and the 4 inch cutting blades.  It won't be fast but you won't ruin your equipment......its always best to use the right equipment for the job.
Reply:As far as reciprocating saw blades go, my favorite is the skill brand (they're a metallic silver).  They've outlasted the lenox by far and cut quicker too.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:If you accidentally turn the saw with an abrasive blade, the blades tend to EXPLODE!!!.  I've never done it with a 7.25 inch, but I blew up an abrasive blade for my 4.5" grinder once and it hurt.
Reply:I've only cut up to 3/16" thick with the same HF saw caldwellcp has.  Before that I used an abrasive cutoff wheel (7") in an old Stanley 7" circular saw.  No way I'd want to use it on 1/4" stock unless it was just an inch or so cut.  The metal circular saw from HF whizzes thru it so much nicer and leaves a clean cut.  The only problem I have with it is how to shake out all the chips before storing it.  They tend to just rain out of it forever and I've not found a simple way to "dump it".  Even though it traps them very well you still need to wear goggles when running it.While I think I'd replace the blade in my HF saw with a Metal Devil when it wears out; the blade that came with it seems to do just fine.Regards,Clay
Reply:I picked up an  evolution circular saw model 230 off ebay for the 9 " diameter blade.   I'll let you now how it worked.
Reply:I don't know how many cut's your making or how long. But like sandy said if you can see if the supplier can sheer it for you. It will be a lot safer and easier. unless you plan on doing this more than once if that's the case then go buy a metal cutting circular saw.I know there expensive but it's worth it.Get the right tool for the job safety first my friend you can get more money but you can't get another finger or hand.    safety first alwaysIf one of those fiber blades was to shatter using it on the wrong saw you would be doing some heavy crying. safety first
Reply:If you don't want to have the supplier cut it, or costs too much, call and see what it will cost to rent a plasma from nexair if you have one (don't know much about Airgas).Might cost you less when you consider how many blades you might have to buy.
Reply:You'll like the Evolution 9".I bought a second, then a 14" Milwaukee. Keep in mind , don't cut hardened steel!  Mild steel only. Otherwise use an abrasive saw.
Reply:Porter Cable makes an electric circular saw specifically for metal. It comes with a special blade. I cut through one inch thick aluminum plate and made six passes on a eight foot long piece and the thing acted like I was cutting plywood! It will cut steel as well. It states in the instructions that it requires no cutting oil on the blade or metal. You do have to keep an eye on the chip catcher though as it fills up rather quick. Makes cuts that look like you machined them and of course you can make your cuts on an angle. Now the  bad new. It's over three hundred and fifty bucks. Still, I think it's money well spent. Good tools are always worth the price.
Reply:7" cutoff blade in my circular saw... abrasive type.***************************************Lincoln AC225 stick welderLincoln HD100 WeldPak flux core wire feed welderThree of the cheapest grinders money can buy
Reply:Go to medfordtools.com , click on the (more info) of the tube bender, scroll down to the Evolution circle saws, look at all three of them, there is a video on one of the pages of them in operation.I've been having the same delimma with cutting 1/4" mild steel plate.  I'm making a winch mounting plate for my Jeep and have to make a 10" cut and a 33" cut.  I have an abrasive blade for my skill saw but that thing is nasty...and tends to wander.  Yesterday I bought a couple blades for my reciprocating saw that are for 1/4" mild steel.  I made the 10" cut and it was great!  "Almost" like cutting through butter...lol  I was very pleased with the speed that it cut through the steel.  It's alot cleaner than my abrasive blade with ALOT less mess.  I have to be careful to keep it straight but thats not too difficult.  One day I might get an O/A setup or a plasma cutter...but until then I'll be using my reciprocating saw.MM175 MIGCutmaster 38 PlasmaCraftsman 30gal compressor4x6 HF bandsaw1hp HF floor drill pressRyobi Cutoff SawAssorted grindersNot enough time
Reply:I looked through my Fastenal catalog last night and came across some blades from Norton made specificaly for 7 1/4" circular saws. They are capable of 8500 rpm, when a circular saw only spins 5400 rpm. I'm going to order some and give them a shot. Will need to get a junk saw though incase things go wrong.Patriot Performance AutoLincoln Power Mig 255CLincoln AC-225 StickVictor Journeyman O/AQuincy QT-5 Compressor
Reply:The Evolution metal cutting saw I bought off ebay works beautifully.  Its the more powerful model 230 with the 9 inch blade.  The demo model saw cost me $220 and the new blade was another $50.  The cut edge of the 1/4 inch plate I have been cutting is really smooth, like glass,  just like or better than with wood.  You have to go/cut slower than wood though.The metal cutting blades are rated at a much higher rpm however the metal cutting saws run at a lower rpm.  Typically wood circular saws run around 5000 rpm (4400 for the more powerful gear drive) whereas the metal specific saws spin around 3500 rpm for the 7 1/4 inch size.  My 9 inch runs at 2700 rpms.  These saw are designed to put out higher torque at a lower rpm so you don't overheat the cutting blade.  Using a metal cutting blade on a wood saw will probably overheat the blade as well as the saw.  May work for a short cut though.One thing from the instructions was interesting.  You should only have the blade stick out 4 mm below the bottom of the cut.  Whereas on wood you generally have the blade depth set to max.  I found this odd but called the manufacturer and they verified it.  It gives more teeth in the cut and it cuts better that way they say.  I have made 3 cuts down a 9 foot 1/4 inch thick plate (27 feet of cuttung) and I am amazed how well it works. Cutting maybe 4-6 inches per minute or thereabouts (maybe a little more but I have not timed it).  If you don't want to buy the more expensive Evolution brand saw, I would recommend buying the one at Harbor freight recently on sale for $99 or also go to Tractor supply (They have the Clarke brand around $130 and the new green colored house brand - forgot the name).  These are all between $100 and $150 but a blade is included.  By the time you buy a couple of blades and burn up a couple of cheap high rpm skill saws you will have that much in it anyway.  Since I started this thread I thought I would give an update with what I found out so far.  I am amazed at how well these work albeit much slower than cutting wood.
Reply:Well I'll be.... Never knew a saw like that existed until I tool a look. I guess I should probably get one of those. They do look kinda like a kids toy, not much detail to the Makita one I was looking at. Bit pricey too. Looks like a handy saw to have though.Patriot Performance AutoLincoln Power Mig 255CLincoln AC-225 StickVictor Journeyman O/AQuincy QT-5 Compressor