Cutting thin (25 - 20ga) sheet metal with table saw & abrasive cutting wheel...thoughts?

[OSULemon]

Spoiler alert - it's already happened, but I can't decide how to feel about it. Mostly I'm wondering if it's something I should consider being okay to do in the future.

I'm helping someone build a shop. He wanted to rip some steel studs to make long, thin angle stock, which we used to secure a first layer of ICF block. He picked up one of these discs at Lowes, brought a Dewalt 10" jobsite tablesaw, and did probably 10 pieces that way:



Anyway, nothing caught fire, melted, or otherwise broke, but I haven't been able to find much about anyone using tablesaws with this kind of abrasive disc to cut ferrous metal of any kind. I read the reviews for that Bluefire disc and seen some success stories with the toothed Steel Demon type blades, but always in regards to using them with regular circular saws.

Any thoughts? Would this kind of use cause eventual damage to the tablesaw? Safety concerns? Is there a better way that's roughly as fast and efficient? Or is this a pretty clever solution that's made possible by a cutoff wheel with the correct size arbor that seems to be made for it?

 

[PoorUB]

I have done it. I wouldn't do it on a good table saw I wanted to keep! It slings molten slag over everything, and the tilt mechanizes, gears, the motor and so on.

 

[finn]

Darwin

 

[Dig Doug]

A skill saw with a demo blade works also in a pinch

a set of metal shears would be ideal

I have a Milwaukee set

but here is a Bauer

 

[drokihazan]

This is a bad idea. Don't do it. You'll ruin the table saw.

Just buy a 3" cut-off wheel, whether a pneumatic one or something like the Milwaukee M12 one.

 

[mike93lx]

All that abrasive material and metal shavings are going all kinds of places that they were not designed to be.

I wouldn't do it on my table saw, but I don't think it's particularly dangerous. The wheel is being loaded in the right direction and the speed is well under the wheel's max

 

[OccupantRJ]

I like quiet And smooth. The three finger power shear as pictured above is what I would be using, or either my Bosch bypass type shear.

 

[rust in the eye]

Have somebody standing by with 9-1 already dialed

 

[OneEyedMan]

I use a sawzall like a jigsaw or a metal blade in a jigsaw to do long cuts in light metal. All that leverage with an abrasive wheel feels like a possible problem if binding occurs.

 

[ctandc72]

All the "It's dangerous" posts - I can't help but laugh. I grew up poor. You did what you had to do to get it done. Would I do that to a table saw I cared about? Probably not. But then again, I wouldn't bother to pull it out. I've got a 20+ year old Skil Brand circular saw with blade designed for metal to cut thinner steel. The saw owes me nothing at this point and it works fine.

Hell, depending I might just grab the grinder, draw a line and use the cut off wheel. I'm sure all of those options are dangerous and not using the 'correct' tool for the job - but if it's stupid and it works? It ain't stupid.

 

[PoorUB]

All the "It's dangerous" posts - I can't help but laugh. I grew up poor. You did what you had to do to get it done. Would I do that to a table saw I cared about? Probably not. But then again, I wouldn't bother to pull it out. I've got a 20+ year old Skil Brand circular saw with blade designed for metal to cut thinner steel. The saw owes me nothing at this point and it works fine.

Hell, depending I might just grab the grinder, draw a line and use the cut off wheel. I'm sure all of those options are dangerous and not using the 'correct' tool for the job - but if it's stupid and it works? It ain't stupid.

I have an older Milwaukee circular saw that my dedicated steel cutting saw. I put a Diablo steel blade in it and cut steel bar stock, and thinner steel flat stock (Up to 3/8" thick) with it all the time. The only down side is it slings swarf all over so a face shield is definitely required.

 

[rlitman]

If you have a junk craigslist tablesaw that's not loaded with sawdust, and some kevlar sleeves to protect yourself from that 8' long ginsu knife you just created, I could see this working. Not particularly well, but it could work. A tablesaw would be turning much slower than the rating of that 7" wheel, so the shrapnel risk is much lower, though the cutting efficiency and speed would ****.

And yeah, the abrasive residue isn't doing your saw any favors. It'll trash the motor and any moving parts inside, and if that motor is packed with sawdust (as can be expected with most tablesaws), there's a real fire risk.

Lenox makes a decent steel cutting diamond wheel. Being made from a steel plate, there's no shrapnel risk. The 7" disc is relatively cheap, but it would also be very underspeeded in a tablesaw. The 10" version would go through a steel stud like a hot knife through butter but is $90, though I suspect you can find something similar from someone else for less.

On Sunday I cut through a piece of train track (ASCE 30, so relatively light stuff made for cranes) with a 4-1/2" disc in my 12kRPM pneumatic turbine angle grinder, and while the diamond disc was a bit small for the job, it got through the rail just fine and looks no worse afterwards. But the interesting part is that my left UNGLOVED hand was absolutely showered in the full stream of sparks for quite a few minutes, and aside from a couple of dozen hairs being singed off, I too was no worse for the wear. At least 3/4 of the hairs around the burned ones are themselves still completely undamaged. There's absolutely no way I could have made that cut ungloved with a conventional abrasive wheel and not have had 3rd degree skin burns (and that much cutting would eat through several 4-1/2" wheels of even the best kind).

My point is, with conventional cutoff discs, most of the sparks you see are the abrasive, and those sparks are hot enough to ignite combustible materials and melt themselves into whatever they impact (I've had lightbulbs turn gritty from them). With diamond cutoff wheels, the sparks are pretty much only the steel being removed, and that's a lot less destructive to the stuff around it.

 

[rlitman]

I have an older Milwaukee circular saw that my dedicated steel cutting saw. I put a Diablo steel blade in it and cut steel bar stock, and thinner steel flat stock (Up to 3/8" thick) with it all the time. The only down side is it slings swarf all over so a face shield is definitely required.

Have you had issues with blade life? My understanding was that the carbide steel cutting blades are made to be used at lower RPMs than wood cutting blades, so the dedicated metal cutting saws run slower to reduce edge chipping (and they also have sealed motors, so the brushes don't ingest metal shavings).

I'm down with the face shield. I use one all the time with carbide burrs and die grinders, but I do try to limit my use of them, because the hair thin and needle sharp swarf just loves to make splinters in your skin. Are the Diablo's leftovers similar, or less bad in this manner?

 

[alwaysFlOoReD]

Personally I wouldn't have a problem using an old table saw and a high tooth count carbide blade to rip a steel stud if that's all I had lying around. Especially if you're trying to get a straight cut. But you need to watch the floppy end after the cut and definitely ppe.

 

[ctandc72]

I think a lot of this is impacted by how often someone is cutting metal. Almost anything can work now and again, but if it's going to be done routinely, that's when more dedicated solutions / tools come into play.

Just my opinion.

 

[The Cobbler]

a plasma cutter works great for this .

 

[woody 73]

Been there and done that, but I was using a piece of **** craftsman table saw, not a good table saw. trust me you will burn that table with heavy slag marks, catch any old sawdust with hot sparks, (great for fire) and you better have tons of protection on. mind you I was using a 10inch fiberboard blade and cutting old wash machines with a thicker gauge metal.

Do I recommend doing hell no, but sometimes you need to complete a job, and you have not many choices. So, kids do as I say, not as I do, if you catch my drift; just don't do it.

 

[PoorUB]

Have you had issues with blade life?

Well, they don't last forever!
I am satisfied with blade life. I will admit that blade life is probably shorted than it should be but acceptable. I have done some larger projects and a few smaller projects on one blade. I screw up once in a while and feed to fast in thin material on it will pop of a tooth or two. Cutting a lot of thicker stock dulls the blade faster.

I was using cut off wheels in a 4 1/2" grinder and I would say the Diablo blade is more price effective that burning up cut off wheels. Plus the cut is relatively cool when done versus using cut off wheels. To me it was a game changer. I don't have a band saw, no room for one, or even an abrasive cut off saw, so it has always been a hacksaw or cut off wheels. Since buying the Diablo blade my desire to have a band saw or abrasive saw dropped to zero. Usually my Milwaukee saw sits on my metal working bench, ready to go.

 

[OSULemon]

I have done it. I wouldn't do it on a good table saw I wanted to keep! It slings molten slag over everything, and the tilt mechanizes, gears, the motor and so on.

This is a bad idea. Don't do it. You'll ruin the table saw.

Just buy a 3" cut-off wheel, whether a pneumatic one or something like the Milwaukee M12 one.

All that abrasive material and metal shavings are going all kinds of places that they were not designed to be.

I wouldn't do it on my table saw, but I don't think it's particularly dangerous. The wheel is being loaded in the right direction and the speed is well under the wheel's max

If you have a junk craigslist tablesaw that's not loaded with sawdust, and some kevlar sleeves to protect yourself from that 8' long ginsu knife you just created, I could see this working. Not particularly well, but it could work. A tablesaw would be turning much slower than the rating of that 7" wheel, so the shrapnel risk is much lower, though the cutting efficiency and speed would ****.

And yeah, the abrasive residue isn't doing your saw any favors. It'll trash the motor and any moving parts inside, and if that motor is packed with sawdust (as can be expected with most tablesaws), there's a real fire risk.

Lenox makes a decent steel cutting diamond wheel. Being made from a steel plate, there's no shrapnel risk. The 7" disc is relatively cheap, but it would also be very underspeeded in a tablesaw. The 10" version would go through a steel stud like a hot knife through butter but is $90, though I suspect you can find something similar from someone else for less.

On Sunday I cut through a piece of train track (ASCE 30, so relatively light stuff made for cranes) with a 4-1/2" disc in my 12kRPM pneumatic turbine angle grinder, and while the diamond disc was a bit small for the job, it got through the rail just fine and looks no worse afterwards. But the interesting part is that my left UNGLOVED hand was absolutely showered in the full stream of sparks for quite a few minutes, and aside from a couple of dozen hairs being singed off, I too was no worse for the wear. At least 3/4 of the hairs around the burned ones are themselves still completely undamaged. There's absolutely no way I could have made that cut ungloved with a conventional abrasive wheel and not have had 3rd degree skin burns (and that much cutting would eat through several 4-1/2" wheels of even the best kind).

My point is, with conventional cutoff discs, most of the sparks you see are the abrasive, and those sparks are hot enough to ignite combustible materials and melt themselves into whatever they impact (I've had lightbulbs turn gritty from them). With diamond cutoff wheels, the sparks are pretty much only the steel being removed, and that's a lot less destructive to the stuff around it.

Personally I wouldn't have a problem using an old table saw and a high tooth count carbide blade to rip a steel stud if that's all I had lying around. Especially if you're trying to get a straight cut. But you need to watch the floppy end after the cut and definitely ppe.

I think a lot of this is impacted by how often someone is cutting metal. Almost anything can work now and again, but if it's going to be done routinely, that's when more dedicated solutions / tools come into play.

Just my opinion.

Been there and done that, but I was using a piece of **** craftsman table saw, not a good table saw. trust me you will burn that table with heavy slag marks, catch any old sawdust with hot sparks, (great for fire) and you better have tons of protection on. mind you I was using a 10inch fiberboard blade and cutting old wash machines with a thicker gauge metal.

Do I recommend doing hell no, but sometimes you need to complete a job, and you have not many choices. So, kids do as I say, not as I do, if you catch my drift; just don't do it.

I should probably just go ahead and admit that the person in question is my father, and, uh...it's my tablesaw. This isn't "General Relationship Discussion," right? I'll just leave it there...

I did not get the sense it was particularly dangerous, once I checked the RPM and realized there wasn't much side-loading. Regardless, did the face shield I placed on the saw get promptly discarded before cutting? Oh, yeah.

Mostly, I was half-expecting a fire from the noticeable amount of leftover sawdust, but luckily not.

Can't say I'm thrilled about the potential damage but I suppose I'll evaluate it once the project is done and determine if it's now his tablesaw.

 

[ctandc72]

I should probably just go ahead and admit that the person in question is my father, and, uh...it's my tablesaw. This isn't "General Relationship Discussion," right? I'll just leave it there...

I did not get the sense it was particularly dangerous, once I checked the RPM and realized there wasn't much side-loading. Regardless, did the face shield I placed on the saw get promptly discarded before cutting? Oh, yeah.

Mostly, I was half-expecting a fire from the noticeable amount of leftover sawdust, but luckily not.

Can't say I'm thrilled about the potential damage but I suppose I'll evaluate it once the project is done and determine if it's now his tablesaw.

If it's stupid and it works...it ain't stupid.

Just saying. Maybe you'll get a nice new table saw out of the deal.

 

[crashmtb]

If it's stupid and it works...it ain't stupid.

Just saying. Maybe you'll get a nice new table saw out of the deal.

 

[OSULemon]

A skill saw with a demo blade works also in a pinch

a set of metal shears would be ideal

I have a Milwaukee set

but here is a Bauer

This is a bad idea. Don't do it. You'll ruin the table saw.

Just buy a 3" cut-off wheel, whether a pneumatic one or something like the Milwaukee M12 one.

I like quiet And smooth. The three finger power shear as pictured above is what I would be using, or either my Bosch bypass type shear.

I use a sawzall like a jigsaw or a metal blade in a jigsaw to do long cuts in light metal. All that leverage with an abrasive wheel feels like a possible problem if binding occurs.

We both have the Milwaukee 3" cut-off tool, hackzalls, jigsaw, hell, he even has a Milwaukee band saw, all immediately available. I'm thinking now it would have worked okay to grab any of those and just freehand it. There was no big tolerance requirement for the cut.

I also like the shears idea; we don't currently have any. Likely there'd be other uses for it. I might push for one.

a plasma cutter works great for this .

He does have a plasma cutter but hasn't used it since he moved. I hadn't even thought of that - thanks!

 

[OSULemon]

If it's stupid and it works...it ain't stupid.

Just saying. Maybe you'll get a nice new table saw out of the deal.

Good point, hence I've said nothin' except to all you lovely, anonymous internet folk. That way, I can be wrong...in secret

 

[tyyost]

It would not have been my first choice but since you already did the deed…

I’d blow the saw out good with compressed air, maybe brush any internals with slag or grit, shoot in some spray lube and move on. In the future I’d probably rig something else up, but otherwise I'm sure you are fine.

 

[seber]

I have a dedicated circular saw for the purpose. If the blade binds it might be a problem, but at least it won't be throwing a knife blade at me.

 

[LopezBart]

I've found the best tool for R-panel is my M12 nibbler; it does a bang up job and collects 95% of the sharp crescents in a little fabric bag. I also have the Bauer - it works well on flat stock like studs, but it's a pain on R panel.

 

[Cheesy1]

Growing up on grandpas dairy farm, we cut tons of barn tin with a skill saw with blade turned backwards. Worked well. Use ear protection. And safety squints.

 

[Fav Onefour]

Growing up on grandpas dairy farm, we cut tons of barn tin with a skill saw with blade turned backwards. Worked well. Use ear protection. And safety squints.

We did the same thing.
Honestly, I don't even remember seeing any other method except big ol hand snips. Those were way too slow. We usually had one guy on the ground cutting and the rest of us hanging off purlins waiting for the next sheet. The sawblade trick kept us moving.

 

[alinc100]

Why not just buy 1-1/2" x 1-1/2" steel angle from the same supplier metal studs are available? https://www.menards.com/main/buildi...xjIj8h3fg9xp_7c95_IE_D_jgwN9CH1DAXRgMmp7YS9Xr

 

[racecougar]

My preference is a 7-1/4" metal cutting blade (carbide tipped, not an abrasive disc). Definitely wear ear and eye protection!

 

[Renegade1LI]

I,ve been waiting for a reason to get one of these

https://store.evolutionpowertools.com/collections/table-saws/products/r10tblx?_gl=1*u8uoud*_up*MQ..*_gs*MQ..&gclid=CjwKCAjwnN3OBhA8EiwAfpTYertdYoO5n25ISXrl9WgtAGlrRgrM7BqxCROYYRtx1VBqPUOzIbHpERoC-rwQAvD_BwE&gbraid=0AAAAACV6D5bcUuYBsL2PTd2ms-lVpw_oo

 

[Aaron_W]

I also like the shears idea; we don't currently have any. Likely there'd be other uses for it. I might push for one.

At HF they have Bauer corded and cordless metal shears for $60, and Hercules for $90, all in the style of the Milwaukee shears. They used to have a cheaper model (Chicago Electric probably) for about $30 which was in the style of the Makita shears posted earlier.

With the 10" Diablo steel cutting blades running $50-80 the HF shears won't cost you much more if anything. Milwaukee $200-300 so maybe more debate there.