Thread: Cutting 1/2" mild steel plate with a chop saw

...Didn't work real well with a 14" makita. The cut seemed to have stalled out and made no progress. Before this I had cut a lot of rectangular tubing with no problem.

Is cutting a 1/2" x 6" mild steel plate possible with this saw? I wonder if I used the wrong sawing technique here. Like I should have made repeated attacks, rather than just pushing the wheel into steel. I'm suspicious that this hardened the steel.

How did I finally end up cutting this plate? Borrowed my neighbor's reciprocating hacksaw.
YouTube - Automatic Hacksaw

Waaaaaaaay back in my younger days my fabrication equipment consisted of a mig welder and chop saw.!!

Yes you can cut that, still have a jig I made using 1/2 x4 bar, bunch of cuts.

If possible cut on the edge and not the flat, if you must cut on the flat, then do not hold constant pressure but jab at it.

Makes a huge mess of grit and wears wheels quite fast.

Forget the grit on the wheel, go as rough as you can.

Originally Posted by MwTech Inc

If possible cut on the edge and not the flat, if you must cut on the flat, then do not hold constant pressure but jab at it.

yeah, maybe next time I can add spacers so that I strike less length of the plate per cut.

Originally Posted by MwTech Inc

Makes a huge mess of grit and wears wheels quite fast.

I regretted buying it instead of a bandsaw almost immediately. Absolutely fouling my workshop with grit.

Right there is a good candidate for the gas axe! For very little money, one can pick up a used oxy/fuel torch setup. With a piece of steel as a straightedge, you could chop that piece of 1/2" steel up in no time, make a lot less mess (though there is still some mess, just easier to clean), and have a lot more fun!

Thinner blade can help a lot. If you are using a 7/64" go to a 3/32" this has helped me a lot. McMaster-Carr

If you are already using a 3/32" then I don't know what to say. 1/2" stock should be well within the capabilities of a 14" abrasive saw.

Originally Posted by pbungum

Right there is a good candidate for the gas axe! For very little money, one can pick up a used oxy/fuel torch setup. With a piece of steel as a straightedge, you could chop that piece of 1/2" steel up in no time, make a lot less mess (though there is still some mess, just easier to clean), and have a lot more fun!

Stainless doesn't cut with oxy-acetylene, without special equipment. Plasma would work fine but is quite a bit more expensive.
A bandsaw would probably have been the best choice here: accurate, less waste, clean edge, set it up and let it work while you do something else nearby.
As someone else mentioned, putting something under one edge of the plate in order to shorten the kerf would be very helpful. The same applies with a bandsaw. A kerf 4" long will catch "sawdust" against the blade causing drag and increased risk of blade breakage.

Here is a link to a video of cutting 5/8" plate with a hand plasma torch. This is the way to cut plate, and it is the lowest cost way to cut (once you get over the initial purchase price!). Jim Colt

YouTube - Powermax1250 cutting 5/8" steel

I know they are expensive but plasma is the way to go. I choked on the price when I purchased mine but if you are going to be working with metal it will pay for itself in short order.

Years ago I did a test to see which blades gave better life with a Makita chopsaw. I do not remember the specifics, but I remember cost per cut was way less with Makita blades. Today I would use my plasma.

Standing it up will do the job, and when the blade wears a bit and doesn't reach the center, just lay it down and cut the middle.
You will use a lot less disc's and cut it quicker with it standing up.

Dave

Probably can't stand up a 6" strip in that saw or he would have done it.

I needed another length of plate tonight, so I tried w/ the 14" makita and this time it worked.

What did I do different?

1) put some spacers so that when the disc comes down, it strikes the plate more like 4 o'clock rather than 6 o'clock, so the bit on the plate was less "long" and then as I ate through it, kept moving the plate deeper into the blade.

2) used chop chop chop motions, rather than trying to make a single cut through.

So I guess blame operator error for my initial question. Thanks for the many replies.

If I read it correctly, you are cutting 1/2x6" stainless bar with a 14" chop saw? The first cut work hardened on you.

The best way to make this cut cheaply is to use a steel-cutting blade on a worm drive saw like carpenters use. Even a 4x6" bandsaw would struggle with this.

A plasma cutter would do this job very well indeed. For the straightest cut, clamp on a straightedge and use consumables that allow dragging the tip. Then just start your cut and drag the torch along the straightedge. Get your speed right and it will look machine cut.

I hate those 14" abrasive saws. They are made for one job - cutting 16 gage steel 2x4s for use in building. Anything very thick at all and they bog down, refuse to cut. And they always make hideous amounts of noise and throw ridiculous amounts of filth. A guy gave me one once and after using it for less than a week I gave it back. He threw it away.

metalmagpie

The OP specified mild steel. The PITA factor is the 6" width.

Abrasive chop saws of the "contractor grade," like the Makita, are messy, noisy crude tools for cutting anything, and at 1/2" are near their limits, but it's still possible to do this job with them.

It's a few thousand dollars outlay to move up to the right equipment.