knots

Limits of Metal Cutting Circular Saw Blades ???

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I have a couple of cuts that need to be made across a 1 3/8" X 9" steel bar.   None of my regular saws will handle a cut of that size.   So I am looking for an alternate, other than a hand held band saw, to make these cuts.

 

My question is can using a metal cutting circular saw blade installed in a industrial duty electric hand saw be expected to make these cuts ?

 

I have had in my a new Bosch CB748ST blade in my stable of tools for a while.   I would be happy if I could complete two such cuts with this blade.   On the other hand I would be disappointed to kill a $40 blade with negative results.

 

Does any one have experience with using a hand held saw with a metal cutting blade for such a task ?

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The electric hand saw is too high of RPM for that.  I would not want to be around when the blade disintegrated as it hit the steel.  Better off to find someone with a horizontal bandsaw.

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stop in to a commercial tool shop or manufacturing facility to ask if they will cut them on their horizontal band saw. More accurate, faster and most likely cheaper than a $40 blade.

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The electric hand saw is too high of RPM for that.  I would not want to be around when the blade disintegrated as it hit the steel.  Better off to find someone with a horizontal bandsaw.

 

 

The Bosch blade is rated for 5800RPM.   My saws rated speed is rated at 4900RPM.   

 

I think you are correct that the larger blades are rated for a lower RPM to hold cut rates, that is surface feet/minute, within an acceptable range for the cutting surfaces .  However my blade and saw are a much smaller diameter than most of the cold cut metal saws, so the RPM can be increased to compensate for the smaller diameter blade to maximize the radial speed.

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I have a couple of cuts that need to be made across a 1 3/8" X 9" steel bar.   None of my regular saws will handle a cut of that size.   So I am looking for an alternate, other than a hand held band saw, to make these cuts.

 

My question is can using a metal cutting circular saw blade installed in a industrial duty electric hand saw be expected to make these cuts ?

 

I have had in my a new Bosch CB748ST blade in my stable of tools for a while.   I would be happy if I could complete two such cuts with this blade.   On the other hand I would be disappointed to kill a $40 blade with negative results.

 

Does any one have experience with using a hand held saw with a metal cutting blade for such a task ?

The blade you have is rated at 13/16" IIRC so no. Torch or bandsaw 

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Greetings Knots,
I have cut a lot of stock like that by carefully marking the stock and cutting from both sides . Your porta ban should be able to cut a 4 in cut. The blade cut is normally only .020 which should allow for some grind clean up.. Just an old boys 2c...
Forge on and make beautiful things
Jim

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For "a couple of cuts", I would buy a good hack saw and a pack of high quality blades. Might be surprised how fast you get through it; stop and rest if you get tired; cut from both sides if necessary.

I've cut 4" round shafting by hand in less than ten minutes. It's a good workout.

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I have a steel cutting circular saw that is similar to a wood saw, but the rpm is a little slower. That is much heavier than the saw is rated for but I bet it would do it if taken slowly.  I agree you might have a problem with a regular speed circular saw. 

 

The saw I have is a Princess auto one (similar to Harbour Frieght)  I question whether it would stand up to daily use but it works well for a couple hours use every few months.

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The Bosch blade is rated for 5800RPM.   My saws rated speed is rated at 4900RPM.   

 

I think you are correct that the larger blades are rated for a lower RPM to hold cut rates, that is surface feet/minute, within an acceptable range for the cutting surfaces .  However my blade and saw are a much smaller diameter than most of the cold cut metal saws, so the RPM can be increased to compensate for the smaller diameter blade to maximize the radial speed.

 

The hand held circular saws for metal I know run at 2200 RPM and can cut ~3" thick material, 9 inch diameter blade.

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The hand held circular saws for metal I know run at 2200 RPM and can cut ~3" thick material, 9 inch diameter blade.

The Bosch blade is made to run on a wood cutting hand held circular saw. 

I have extensive experience with them. 

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The Bosch blade is made to run on a wood cutting hand held circular saw. 

I have extensive experience with them. 

 

 

Have you tried cutting thicker material with multiple passes.   My thought is that a properly jigged cut guide to keep the cuts in line, and using multple light cuts could produce accurate cuts if applied with care.

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Have you tried cutting thicker material with multiple passes.   My thought is that a properly jigged cut guide to keep the cuts in line, and using multple light cuts could produce accurate cuts if applied with care.

I
Will answer this but frankly I am tired of having my experience constantly challenged on this forum.
The reason yours is a bad idea is because of lenght of blade exposure.
Metal should. Always be cut with as short of an angle as possible.
Pushing the guide plate almost all thevway down so as to make a shallow cut means that one is making the longest cut possible, the exact opposite of what is best fr the saw motor and the blade.
Bocsh rates the blade at 13/16" hence 3/4"thickness is max.
Could it work?yes.
Will a wood saw last long doing so? No

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arftist, if people wouldn't appreciate your experience they would not ask you to share it.
I for my self have only experience with aluminum when it comes to hand held circular saws.
I knew there are metal only hand held circular saws with lower rpm, but the bosch blade for higher rmp was new to me.
And I like to read about stuff thats new to me :) no experience challenge here, only asking you to share yours- and for that I am thankful

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arftist, if people wouldn't appreciate your experience they would not ask you to share it.
I for my self have only experience with aluminum when it comes to hand held circular saws.
I knew there are metal only hand held circular saws with lower rpm, but the bosch blade for higher rmp was new to me.
And I like to read about stuff thats new to me :) no experience challenge here, only asking you to share yours- and for that I am thankful

Read this thread and maybe you will see why I am over it.

 

 

I get a lot of PMs thanking me for this or that tidbit or whatever then I get this treatment when someone else abuses a newcomer and I am stupid enough to point it out. 

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Knots, did you finally get your cut done? I'm using a cheap cut off wheel for a wood saw cutting through 1" square grating without too much trouble. Just have to remember to go slow and steady.

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I say go for it!!! If your blade is rated for the rpm that your saw will output, the blade is designed for cutting steel, and the blade has roughly 32 tpi then use say do it. I would.... Just be sure you understand the dangers involved and be as careful as possible, use all guards, gloves, glasses, face shield, and ear plugs. I have a metal cutting circular saw and I've personally cut 1"thick steel plate with absolutely no problems or dangers. The main issue here is the rpm rating. Other than that, I don't see a problem. Just keep in mind that, unless your circular saw is a worm gear drive saw, you could burn up the saw. And with that thick of material, that's a lot of surface area the blade will be in contact with so you may burn the blade as well. 

Fire up that saw and post pictures of results!!

-Hillbilly

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 M Cocrhan  and Hillbilly thank you for your inquiry about progress of my project.  I have not made those cuts yet.   For now I have postponed this and other projects because of the passing of my wife.   I plan to be back in my shop for some quality time beginning in May.   I have settled on testing an alternate approach not yet discussed and will report the outcome of this trial when tried.

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You have my deepest condolences Knots. She, you and yours are in our prayers. Be well brother.

Frosty The Lucky.

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I have chewed through a lot of 5/8 inch plate with a worm drive saw and a metal blade. It sucks big time. Wear a welding jacket and gloves and neck, face head protection. Those chips are hot and sharp and go everywhere, in big piles.... I don't know about 1 3/8 plate. That might be a bit too much for the saw. It would be cheaper and easier to use a torch.

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