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qroger
Thu 02 September 2010, 14:19
This past weekend, I stopped at a yard sale and in a lapse of judgement, purchased a radial arm saw. Everything appears to work, but, I don't really need one! Faced with the gimlet eye of the designated adult at my house, I thought it might be just the thing for cutting pipe, if: 1.) I could come up with a metal cutting carbide blade, (no problem), and 2.) I could slow the saw down to the recommended revolution rate. That is where the MM brain trust comes in.

Would a pwm device work? The saw is currently brushed am motor of about 1hp. It's at home, so I am not sure.

Would it be easier / possible to modify a MM belt drive - speed reducer for the task?

Thanks
roger

smreish
Thu 02 September 2010, 14:22
Roger,
It would be easy to put a motor controller to the saw blade and adjust to the proper RPM for the "special" blade. That accounts for speed and not torque. Not will cost about as much as buying the harbor freight or Milwaukee version. Best bet - ebay or craigslist the saw and get one for the purpose. My 2 cents.

bradm
Thu 02 September 2010, 14:46
I'm with Sean, especially if it is a radial arm saw and cuts pulling forward away from the fence. If it were a grossly overpowered chop saw, cutting by pushing downwards, maybe there would be enough torque left over. Or, if the motor was three phase and could be used with a VFD. But again, you'd spend more than a cheap chop saw will run you, and get an inferior result.

Jan de Ruyter
Thu 02 September 2010, 23:53
Just use a normal carborundum blade. For steel, push the blade towards the fence, for wood, pull it away from the fence. No need to modify the motor. You might need a little yellow, plastic bush to fit the blade to the shaft.

hennie
Fri 03 September 2010, 01:00
I have seen to many accidents with those saws,thats why there are 2 standing in my old Jhb workshop rusting away.

MetalHead
Fri 03 September 2010, 06:38
Sell that thing and go get one of these.

http://www.harborfreight.com/catalogsearch/result/?category=&q=chop+saw

May not be the best, but get the replacement insurance. IF you take your time setting up the cut it should work ok. Not a wet saw but should work.

I have a Delta like this and it does everything I need it to do.

normand blais
Fri 03 September 2010, 07:01
maybe one could be use for z slide,it already has a tool older and motor

qroger
Sun 05 September 2010, 20:32
It is sort of just something to puzzle with. One of these: http://www.harborfreight.com/12-inch-sliding-compound-miter-saw-with-laser-guide-98194.html is what they came up with to simulate part of the radial arm saw capabilities. I know from experience that part of the bad reputation of these comes from operator error and not locking everything down, before one lets the horses out of the barn.

I do think though, that the least that would be needed to keep from eating pieces of pipe would be a vice instead of a fence.

I have never used one of the carbide tooth metal cutting blades, but apparently they cut rather than burn through, and do not produce the shower of sparks as an old style cut off saw does.

The harbor freight metal cutting band saw is great, but slow, and a pain for any thing but 90's.

lumberjack_jeff
Sun 05 September 2010, 22:26
Apparently HF stopped selling my metal cutting circular saw (think steelmax).

The second works pretty well, but then again I baby it (inasmuch as asking it to chew through a piece of 3/8" angle iron can be done nicely)

Lots of chips, but no sparks.