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View Full Version : old DeWalt radial arm saw - cut metal with modern carbide blade?



metalmagpie
07-16-2019, 08:29 PM
My father-in-law is now in his late 80s. He bought a DeWalt RAS in 1960 and has owned it ever since. He's not doing much shop work anymore and probably won't. He asked me if I would put new bearings in the motor since it started making bearing noise. I went up there today and took out the motor and brought it home.

I had not realized how heavily built the old DeWalt saws were. I don't want to use the word "bulletproof" but terms like "well designed" "heavily built" "machined iron castings" seem to apply.

Since he's clearly going to ask me to take the saw away from his shop and do something reasonable with it, I'm wondering if I could get away with using a steel-cutting carbide tooth saw e.g. https://tinyurl.com/y4apwds9.

What do you think? Genius or Darwin award?

metalmagpie

v860rich
07-16-2019, 08:43 PM
It says it has a 3000 rpm limit, so I guess you need to know the speed of the motor you have.

THANX RICH

Arcane
07-16-2019, 08:47 PM
Don't radial arm saws cut with a climbing cut? That should be interesting on metal.

Mcgyver
07-16-2019, 09:04 PM
Make it convertible to a surface grinder as well :D

People cut AL on wood saws, can't see it working out with steel....work out the cutting speed at 3000 rpm, yikes.

Lew Hartswick
07-16-2019, 09:17 PM
I use a Craftsman of that vintage to do aluminum but wouldn't even think of doing any steel on it. There are many blades with 0 rake or even neg rake that can be used on radial saws for non ferrous material.
...lew...

SLK001
07-16-2019, 09:36 PM
A radial arm saw blade has virtually no rake to prevent it from climbing onto the work piece during a cut. If you ever had to fight a RA saw with the wrong blade, you know what I mean. The RA blades for wood are fairly rare nowadays - I doubt that you can find one for steel - plus the speed is too fast for steel.

lakeside53
07-16-2019, 10:03 PM
You'd be crazy. I had one for 25 years and I can testify that Radial Arm saws are nasty under the best of circumstances. You will get hurt.

J Tiers
07-16-2019, 11:04 PM
Don't radial arm saws cut with a climbing cut? That should be interesting on metal.

We had a very contentious discussion of that a couple years ago. Some of us prefer to NOT climb cut, and it is just a matter of which way the saw is moved, anyway. The climb cutters had rafts of reasons why climb cutting wood was safer, and avoided all problems.... but I think everyone came away with the samr opinion they went in with.

AFAIK the speed is 3450RPM, and so too fast for the 3000 RPM blade mentioned in another post, anyhow.

I might cut aluminum, NOT climb cutting, but there is no way I would ever consider climb cutting steel with one. Or just cutting steel with one in any way.

The Metal Butcher
07-16-2019, 11:34 PM
Steel on wood tools? Yes, done that. (https://www.youtube.com/watch?v=DqdpvaXUWo4)

Steel on a radial arm saw? They scare me enough, don't need to up the ante.

Tundra Twin Track
07-17-2019, 01:30 AM
Last week I picked up 4 FS Tool 14" 100T blades for wood and 2 12" 100T for non ferrous metal they are carbide and were priced right.

The pic shows tooth profile of the 12".https://i1371.photobucket.com/albums/ag292/tundratwintrack/image_zpsl4qqrjir.jpg (https://s1371.photobucket.com/user/tundratwintrack/media/image_zpsl4qqrjir.jpg.html)

Ian B
07-17-2019, 02:06 AM
I don't see why you shouldn't do it. After all, you can buy them: https://www.amazon.co.uk/Evolution-RAGE3-DB-Double-Multi-Purpose-Sliding/dp/B006BRVQ9K

The one caveat is that you use a blade designed for cutting metal - Rage (and others) sell them.

I'm guessing that your father-in-law's old De Walt radial saw is significantly beefier than the ones you can buy. Indeed, check the motor RPM, and buy a blade of a suitable diameter to give the required cutting speed. I have the hand-held version of the Rage saw, and it does what it says on the tin - chops through angle iron etc, no problems. The chips aren't even that hot. But wear ear defenders...

Ian

Tungsten dipper
07-17-2019, 06:32 AM
After 20+ years using a radial arm saw...... DON'T DO IT! They are not ridged enough and your work MUST be clamped down. I've cut 2" thick aluminum with one and I wouldn't do it again!

epicfail48
07-17-2019, 08:50 AM
Ive used a metal cutting blade (lennox i believe) on a miter saw to cut steel pretty well, but i wouldnt want to try it on a radial arm saw. My concerns are the same as everybody else, lack of rigidity and nothing preventing the carriage from self-feeding through the material. Now, in would im a believer that self-feeding can easily be prevented with proper technique and blade selection, but steel and wood arent all too similar. You can get around the self-feed issue by always starting the carriage at full extension and pushing it through the cut, rather than pulling, but personally i feel that any slider mechanism moving the blade through metal is just asking for trouble. Personally i wouldnt even want to use a metal cutting blade in that Evolution SCMS that was posted, anything that could kick the blade in unexpected ways when cutting steel is out for me. Best to keep things as rigid as possible

Seastar
07-17-2019, 09:37 AM
I have a Sears RAS that I bought new almost 40 years ago and have used successfully for wood.
It has tried to kill me so often I won't even think about using it for metal.
I feel like I need military armor when I use it for wood!
Seastar

J Tiers
07-17-2019, 11:39 AM
Ive used a metal cutting blade (lennox i believe) on a miter saw to cut steel pretty well, but i wouldnt want to try it on a radial arm saw. My concerns are the same as everybody else, lack of rigidity and nothing preventing the carriage from self-feeding through the material. Now, in would im a believer that self-feeding can easily be prevented with proper technique and blade selection, but steel and wood arent all too similar. You can get around the self-feed issue by always starting the carriage at full extension and pushing it through the cut, rather than pulling, but personally i feel that any slider mechanism moving the blade through metal is just asking for trouble. Personally i wouldnt even want to use a metal cutting blade in that Evolution SCMS that was posted, anything that could kick the blade in unexpected ways when cutting steel is out for me. Best to keep things as rigid as possible

If you think about it, the RAS is about the same thing as a "Skilsaw" (hand held circular saw) with the improvement that it is guided in a straight line by a rolling carriage which also "tends to" hold it down for a consistent depth of cut. ("tends to" is a deliberate use of words)

My attitude toward the RAS is that "of you would not do it with a hand Skilsaw, you need to think at least twice, and maybe not do it with an RAS". I would NEVER CONSIDER doing a "climb cut" with a Skilsaw, so I do not do it with the RAS. I would NEVER CONSIDER trying to cut steel with a Skilsaw, so I do not do that with the RAS.

And so on.....

The rest of youse can do as you like...... whatever floats your watch.