Metal cutting - oxyfuel cutting, plasma cutting, machining, grinding, and other preparatory work.
A36
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    Fri Mar 09, 2018 3:38 pm

What do you guys (and gals) think about converting a table saw for small stock steel cutting? I have an adjustable speed table saw (Shop Smith) and would use the 10" Diablo Demon ferrous blades with the miter fence and the saw dialed in to the correct RPM.
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    Sun Nov 19, 2017 10:09 am

You need to slow the RPMs down. It wouldn't be wise to cut steel this way even if you could slow the saw down.
The kick back would go right through you. Your hands wouldn't be strong enough to hold the piece while cutting.
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    Tue Sep 12, 2017 8:31 am

I’ll skip the “ you can’t safely do it” speech because I’m sure you can by going slow and keeping it controlled.

Second. If you can get RPMs slow enough then yes. Speed kills carbide. The abrasive chop saws turn some where around 3600 rpm where the dry cut saw with carbide toothed blade spins closer to 1500rpm.

Between the dry cut chop saw and the skill saw style saws I wouldn’t see why it won’t get the job done.

What exactly are you cutting?

And btw. It’s really loud so, double ear protection.
noddybrian
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    Thu Jan 24, 2013 12:13 pm

In theory it's possible - I would certainly consider in a jam for aluminum but it's going to be hell on the saw & especially so attempting steel - not many are variable speed - the few that are rarely make the same kinda torque at low revs required for metal cutting as they do flat out plus the gearbox teeth are not intended for that sort of shock so I think you will either smoke the motor or shred the gearbox after very little cutting - I did the same with a " Skill " type saw prior to buying an Evolution 230 - also the purpose made steel saws are well guarded - a table saw is going to throw hot metal straight at you which is quite unpleasant - plus as mentioned the vibration holding the piece as opposed to the saw will be harsh - if you already have the blade & it fit's give it a try & let us know how it went - if you have to buy a blade I would'nt - put the money to a better method ( but that's just me )
A36
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    Fri Mar 09, 2018 3:38 pm

I haven't set up the saw to test yet but it does have a variable sheave pulley to vary the speed down to about 700 RPM. It's an old Shopsmith for those of you who are into woodworking. I'd only be cutting small steel tubing and angles and was looking for a way to avoid spending $400 on a dry saw or a cheap but dirty abrasive saw. The hobby is staring to get costly and I have a plasma cutter on my wish list...
noddybrian
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    Thu Jan 24, 2013 12:13 pm

OK - I had'nt imagined your saw correctly - I take it the thing is quite well made with a separate motor if it's belt drive so ignore the comments on motor & gearbox - 700rpm is way slower than you need so everything seems fine to try - just be aware of the chips coming at you & the harshness holding the metal - larger pieces weight will damp this out - also the quality of blade & how well it runs for true will effect this - be interested how this turns out.
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I would second the thought that the most difficult challenge you will face is holding onto the work piece and getting a slow, steady, controlled feed. Maybe if you are cutting small angle and tube as you describe you could cobble up some sort of work-holding fixture or gadget to help with that.

There is likely a reason that you don't really see commercial versions built like this. But I don't discourage anyone from an experiment. Just try to think through all of the ways it could go wrong and take the common sense precautions to protect yourself from getting injured. Please do post your results and we'll all learn something!
LanceR
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Well, I've never cut much steel on a tablesaw but have cut a boatload of aluminum, copper and brass sheet and plate up to 2" or so on 3 and 5 HP 10" Delta Unisaws, a 10" sealed motor contractor saw and on a 16" Oliver 260D sliding table tablesaw using appropriate non-ferrous metal blades.

Securing the stock being cut is straightforward to prevent/reduce kick-back with common tablesaw accessories such as finger boards or one-way feed roller and/or a crosscut style sled or by rigging up a sliding crosscut table. The sled or crosscut table would get my vote due to better feed rate control and stock retention.

My experience has been that chips are not a big deal as the saw cuts down through the work piece so the vast majority of chips get ejected under the saw's table. I did wear a heavy leather apron and face shield though as there are still some chips flying about and their trajectory can curve pretty sharply in flight. Using a stick cutting lube on the blade every now and then (or smeared down the cut line) helps keep chips from bonding to the teeth and makes for a cleaner cut.

Slow feeds are in order to help avoid shock fractures of the teeth and to reduce the chance of kick-back. I don't know if ferrous metal blades with the anti kick-back humps in front of the tooth gullet are available but if they are one of those would get my vote as it would reduce the chance of both kick-back and of the teeth getting damaged by taking too big a bite.


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Oinions opinions. Mine is go get a used Milwaukee portaband and rig something up/cut by hand. $150 or so and you're all set for small work. You'll screw around a day or two but you can make something to do a good bit of work.
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