Cutting sheet metal with sliding Miter saw?

[Fender1325]

Guys I got a Kobalt sliding miter saw (10" blade) for free from my father in law who I was helping move some stuff.

Im learning welding, making boxes out of sheet metal as projects but I use my 4.5" angle grinder. The angle grinder throws all kinds of sparks and doesnt cut very straight either.

Can I use the sliding miter to cut sheet metal and what blade do you recommend if so?

 

[theoldwizard1]

They do make special "ferrous metal" blades. Check HD or Lowes or Menards or online.

Proper clamping (not just hand held) as close to the blade as is reasonable is important.

 

[Ramper]

Most will spin the blades TOO FAST for cutting metal.

 

[Fender1325]

That was one of my main concerns.

Just checked my saw and it says it spins 4800 RPM max with no load

 

[jakemac]

On the plus side, you'd get a chance to get the phone number of the cute chick driving the ambulance.

 

[Fender1325]

I saw a steel cutting blade at lowes online and it says its max rpm was 5200, and with no load my saw maxes at 4800. So, is this a no go or what?

 

[HammerMechanic]

They can work. But definitely not the best choice.

 

[jakemac]

I saw a steel cutting blade at lowes online and it says its max rpm was 5200, and with no load my saw maxes at 4800. So, is this a no go or what?

Those blades are intended for a chop saw, not a sliding miter. I'm not sure that a sliding miter saw is built well enough for the abuse that cutting metal can cause.

 

[kmacafee]

Harbor Freight has cheap chop saws. Get a decent blade and they work well,

 

[volleyball]

The blades for a circular saw should work ok. I'd put a scrap piece of wood on top and cut both at the same time.
I've used mine several times for non ferrous metal, never steel.

 

[Fender1325]

Id be cutting sheet metal - i think its mild steel. The blade description online says will not for wood

 

[volleyball]

I've cut wood and steel in a circular saw many times. Try it on scrap.

 

[theoldwizard1]

Most will spin the blades TOO FAST for cutting metal.

******** !

Look at Diablo Steel Demon Metal Cutting Blades. They are specifically designed for cutting steel with a circular saw

The blades for a circular saw should work ok. I'd put a scrap piece of wood on top and cut both at the same time.

Excellent suggestion for cutting thin metal ! Make sure it is clamped down well.

 

[theoldwizard1]

Id be cutting sheet metal - i think its mild steel. The blade description online says will not for wood

It will tear through thin wood (1/4" -3/4") but will leave a very ragged edge on the wood. The wood is only needed on thin metal.

 

[zkling]

Sheet metal, especially steel is going to be a bit wild and will need to be clamped thoroughly even sandwiched between wood pieces. They work pretty good for cutting extruded aluminum sections though. How large and thick of sheets are you talking?

 

[Ign]

Sheet metal, especially steel is going to be a bit wild and will need to be clamped thoroughly even sandwiched between wood pieces. They work pretty good for cutting extruded aluminum sections though. How large and thick of sheets are you talking?

This was my first thought. You need to clamp or hold down the entire sheet, particularly on both sides of the blade. It'll vibrate and buck. And I'd be really leery of using the "sliding" part of the saw.

I know it's far less convenient but a shop with a shear would do several cuts for you cheap.

 

[cheechi]

why wouldn't you just get a bandsaw? a cheapo HF or Ryobi would do at least as clean a cut as what you're attempting. And considering the cut capacity isn't going to be that much the sheets can't be that big; should be about the capacity you'd be getting from a benchtop bandsaw anyway.

 

[Flattie]

I was given the exact saw for Christmas. Nothing fancy, but I like it. It has 5 warnings in the instruction manual that it is NOT for cutting metal. I am not a stickler for rules, but I wouldn't attempt it repeatedly with this saw. Stupid **** happens fast. You only get a pair of eyes and a few key limbs in this life. Me personally, I would really look at better options

 

[Zrexxer]

I can't believe anybody is actually thinking this is a good idea. It's like I've said before, people will work harder to find a way to justify doing things wrong than it ever would have taken to just do them right to begin with.

 

[Farmall450]

I can't believe anybody is actually thinking this is a good idea. It's like I've said before, people will work harder to find a way to justify doing things wrong than it ever would have taken to just do them right to begin with.

I'd have to agree with this, while it can be done, it really shouldn't be. Pick up a chopsaw, bandsaw, etc, it'll likely serve you well.

 

[Fender1325]

I can't believe anybody is actually thinking this is a good idea. It's like I've said before, people will work harder to find a way to justify doing things wrong than it ever would have taken to just do them right to begin with.

Hence why i asked if its okay.

The saw was free and I need to cut sheet metal straight with nice 90 degree angles.

Im not sure a bandsaw would cut it straight unless I had a really good fence to ride on. I dont see that happening in a cheap bandsaw.

I also have jig saws and read online you can buy blades to cut that with. I could clamp wood on and ride that for a straight line perhaps.

This sheet would be no thicker than 18 gauge.

While we're on the topic though, Id eventually like to build a smoker for my dad (like an upright box about the size of a "larger" mini fridge. Maybe 3 feet tall. What tool would somebody use if they need to cut a good straight line several feet long?

 

[SeniorCitizen]

To do sheet metal work get sheet metal tools. Try a scratch all, a straight edge and tin snips. A portable hand held electric shear will cost far less than an ambulance ride.

 

[cg81]

I just picked up a milwaukee metal cutting circular saw. It will cut through metal just like a regular circular saw goes through wood. It has a special metal cutting carbide blade. So far I tested it on a scrap piece of 4 inch channel and it went through it with ease. The cut is very nice and square. It was still cold to the touch and requires no grinding. You can get good cuts on sheet metal by clamping a straight edge to guide the saw down the length of the piece. Check it out on YouTube, there are several good videos of it in action and that is what ultimately sold me on it.

 

[nine4gmc]

I'd go with hand shears before trying to cut it with a sliding miter saw, that sounds like a good way to end up in the hospital.

As mentioned, it would need to be sandwiched on both sides of the metal, on both sides of the blade.

If you can't find a band saw and dot want to do it manually with hand shears, try a jigsaw.

 

[Fugio]

You could drive with your feet, but thqt doesn't mean it's a good idea.

That being said, I cut metal with my table saw all the time.

 

[slyonedoofy]

A month ago I watched a guy build a aluminum handrail using a slide compound.

He would cut slowly forward then pull the blade backwards across the end cut to knock off the burrs.

Seems to work great for him.

It wasn't sheet metal. Not sure if that's a good idea.

 

[alwaysFlOoReD]

The problem I see with a sliding miter saw and sheet metal is the teeth. If you pull like normal it's hard to control [especially the last inch] as the teeth will want to pull into the metal. And if you try to push the saw the teeth will try to lift the sheet off the table. I suggest a circular saw with a carbide blade with a negative tooth hook. I use one all the time for steel siding and have used the same blade for plate, channel, angle, tube, and pipe up to 1/4" thick. I recently bought a blade at KMSTools for ~$40.00

Richard

 

[deuces]

jigsaw, metal cutting blades, straight edge guide, cutting fluid, clamps. works well, fairly accurate, not very dangerous, but it's slow.

 

[nine4gmc]

A month ago I watched a guy build a aluminum handrail using a slide compound.

He would cut slowly forward then pull the blade backwards across the end cut to knock off the burrs.

Seems to work great for him.

It wasn't sheet metal. Not sure if that's a good idea.

I worked for an aluminum window company once and we used a standard miter saw with high tooth standard carbide blade to chop the frames to length. Totally not the same as cutting thin sheet metal but still dangerous. A coworker lost the last digit on one of his fingers just before I quit. The saw blade jammed up and flipped the frame on end, severing the tip of his finger against the backstop... I can imagine sheet metal taking a finger or flopping up in your face removing your nose or eyeball easily...

 

[egdede]

If it is a nice saw I wouldn't want any metal shavings any where near it!!!

 

[crewchief888]

i cut most of my sheetmetal with a 4 1/2" angle grinder.

i'll break out a pair of snips if i'm cutting thin aluminum sheet

actually i cut all my sheet steel (up to 1/4") with a grinder.

pipe, tubing, angle, and channel i cut with an abrasive chop saw.

 

[DonPowers]

I use a 7" Metal Devil, which has a no-load speed of 3500 RPM, with their 68 tooth thin steel blade for cutting metal roofing panels, does a great job.

The saw had no problem cutting 1/4 inch steel with their 40 tooth steel blade.

http://www.mkmorse.com/products/ind...ww.mkmorse.com/products/index.aspx?product=75

 

[Jeeper]

I bought one of those diablo steal demon blades and put it in an old circular saw. I was very impressed with how it cut and how fast it cut. The blade runs cool and not quite a messy as an abrasive blade. The blade was $40 and can be purchased at home depot or northern tool. I will be my go to from now on for cutting sheet or even plate (as long as it's not too think).

 

[volleyball]

I cut a bunch of metal wall panels with a plywood blade. The thing is to get a blade with a lot of teeth and most important is teeth that do not bend to the sides.
You can also get pieces sized when you buy them so you don't have to cut them.