So this is the saw from the back. The original 1hp that came with it had gritty bearings, and I haven't ordered more because I've heard too many reports of that 1hp motor not having enough ass.
So I put one of my treadmill motors on there.....
...But I don't have a proper controller as it's a brushed DC motor. So...
First thing is to rip out a microwave transformer and rewind the secondary so it steps down to about 47vac, which will make this ~6000rpm motor run at about 3500 after it's rectified...
...Then rectify and smooth with a giant and dangerous capacitor, and add a giant flyback diode so nothing gets fried from back EMF from the motor when it gets shut off.
This has been an object lesson in why electronics are as complicated as they are. This *does* work, and I made the sled you see, along with a bunch of tenons, with this setup. But the problem is the motor is only running at half speed (that's why I stepped down the AC), and with it being a fixed voltage, it gets bogged down pretty easily. Like, I have to crawl through 1/2" plywood.
I already started soldering together a PWM circuit based on a 555 timer, which will drive a giant MOSFET, but the problem is I really need a hall effect sensor on the pulley, and I need to feed that into an Arduino, and I need to write code to detect the sensor input, sense when it's lagging, and adjust the MOSFET square wave on the fly so that I can pump the voltage up (it'll run for at least short bursts at *162* volts!) and get the 1.75hp this motor is
supposed to be delivering.
None of that bull$#@! cuts any wood though, which is why I got this off of CL:
Which I got hooked up to my 220 outlet and got running, but before I could even get a full erection, I got treated to a fantastic blue light show, and got to smell burning enamel the whole time I was bumbling out of my dark shop.
So if anyone knows how I can get a 2+hp 3450 induction motor that isn't going to fry itself in 60 seconds or less for under $100, I'd really like to know... because it'll save me having to learn more electronics. It's neat, but it's not really plan A.
Connect With Us