Boy, don't post in the Metalworking forum

[Bob Jones 5443]

In early February I posted this cry for help over in the Metalworking forum, thinking that was the most appropriate place:

A rectangular fragment of a saw plate floating around in my shop was intended as a scraper. It turned out to be perfect to use to extend a saw kerf into the pin boards in half-blind dovetails. I was delighted that the rectangle is exactly the thickness I need for the task (0.025”), so it is in use. But it’s about an inch wider than it needs to be. I’d like to trim it down to make a more elegant tool.

I cut wood. I’m out of my depth when faced with cleanly cutting a tool steel plate along a straight line. What are some options I might already have in my shop?

I don’t have a dedicated metal grinder, but I have a Dremel, cordless drill, and drill press.

Five weeks and not one response. And it's still in the top three threads.

[Oskar Sedell]

what about breaking the extra inch off? clamp it tightly along the break line (+ a little margin) and then bend it with pliers or hammer back and forth until it snaps. Should go fast with saw temper. Then draw file down to the line.

[Bohdan Drozdowskyj]

Put deep scratch on each side of the plate before bending back and forth.

[Jim Matthews]

Depending on the hardness of the plate, hacksaw (slowly, by hand) along a scored line.

File to desired dimensions.

*****

Some sawplates are hardened beyond rc 60 and my hacksaw blades just "skate" off.

[Rob Young]

In early February I posted this cry for help over in the Metalworking forum, thinking that was the most appropriate place:

A rectangular fragment of a saw plate floating around in my shop was intended as a scraper. It turned out to be perfect to use to extend a saw kerf into the pin boards in half-blind dovetails. I was delighted that the rectangle is exactly the thickness I need for the task (0.025”), so it is in use. But it’s about an inch wider than it needs to be. I’d like to trim it down to make a more elegant tool.

I cut wood. I’m out of my depth when faced with cleanly cutting a tool steel plate along a straight line. What are some options I might already have in my shop?

I don’t have a dedicated metal grinder, but I have a Dremel, cordless drill, and drill press.

Five weeks and not one response. And it's still in the top three threads.

If you have files in your shop, look through them for one that looks a bit like this :
File-Tang-300x200.jpg

You want something with a single or double cut row on it and the "teeth" need to get all the way to the edge of the file and form a sharp corner. A triangular file may work as well but if the teeth on it have been used much, the corner may be round now.

Use the corner of the file to scratch a line where you want to break or maybe just a little bit longer. Scratch both sides nice and deep.

Clamp into a vice with the scratch line at the edge of the vice jaws. I've done it with both the waste and keeper piece out of the vice, both seem to work but there may be a reason to align it one way vs. the other. I think I've always put what will be the smaller part in the vice jaws. Use a metal worker's bench vice if you have one but a woodworking vice will do.

With a good pair of leather gloves on your hands, snap off the steel. You may need to flex it back and forth a few times. But saw plates have always snapped on the first bend for me.

Now you can use your file to go back and clean things up to the line. And maybe a little light tapping with a hammer to straighten the edge if it curled.

[Stephen Rosenthal]

On good terms with your neighbors? I’ll bet one of them has an angle grinder they would let you borrow. They’re almost as ubiquitous as cordless drills these days. I bought a brand new Makita at a garage sale for $10 a few years ago and am amazed at how much I use it. With the proper grinding wheel it would make quick work of your saw plate.

[Jim Koepke]

I don’t have a dedicated metal grinder, but I have a Dremel, cordless drill, and drill press.

My Dremel is mostly used with their little cut off wheels to cut hardened metal.

https://sawmillcreek.org/showthread.php?229968

jtk

[Bob Jones 5443]

Thanks, folks. I'll see. I need the cut line to be straight, square, and smooth. I might just use my monster "tool" as it is to pound out the kerfs.

But this proves my thesis: six replies in one day vs. zero replies in five weeks. I'm sticking to the cave over here with the rest of us Neanderthals. It's safer by the fire.

[James Pallas]

Be absolutely sure to wear good eye protection when snapping tool steel. It tends to shatter violently and can bounce and come from behind on the ricochet.

[Rick Dettinger]

If it's a saw that's made to be sharpened with a file, like most are, it will be around 50 to 52 on the Rockwell scale. Hacksaws should work, with a fine tooth. I use 32 TPI.
I usually use my Dremel Tool with an abrasive cutoff wheel. These will cut hardened metal like pad locks. I use a straight edge like a strip of wood and go slow. I have used the Dremel for cutting off stove pipe, which works well. I have also cut Stainless steel sheet on a range hood install. Just take your time and have spare wheels on hand. I have re profiled knife blades that way, taking one cut and quenching. I am a big fan. It's about the only thing I use my Dremel for. And, I second using eye protection and gloves.

Best,
Rick

[Jim Koepke]

Thanks, folks. I'll see. I need the cut line to be straight, square, and smooth. I might just use my monster "tool" as it is to pound out the kerfs.

But this proves my thesis: six replies in one day vs. zero replies in five weeks. I'm sticking to the cave over here with the rest of us Neanderthals. It's safer by the fire.

For a long time my 'kerf extender' was a piece of broken saw plate that was also used as a scraper.

Think of it as a two in one tool.

jtk

[Russell Nugent]

I'd mark the line i want to follow, make the cut with either a hacksaw or Drexel and then file it down to the line

[Andrew Gibson]

Remember, this is the cave, make sure to use your egg beater or treadle Dremel.

[Mark Rainey]

I did get some love in the metalworking forum in the past with this. As Rick said use a fine toothed hacksaw blade 32TPI and file afterwards. I also picked up a carbide rod for my hacksaw for $5. I worked even better. And I see some Stanley carbide hacksaw blades for sale for about $10 that look very interesting. Anybody use that version? As Andrew says, you gotta do this without electricity in Neanderland.

[lowell holmes]

I would use my band saw with a metal cutting blade.