CX706 1HP Brushed to 2HP BLDC

[slow-poke]

Well thanks to DavidR8's surplus motor, my little 10x22 is sporting some new found power, a few images.

The first image is the interesting one, the 2HP BLDC motor is smaller than the original 1HP brushed, technology moves along.

More or less a bolt in, same flange dimensions, Needed a pulley for the larger shaft 14mm vs. 12mm. Made a new control panel to squeeze in the E-Stop.

So now I have a surplus 1HP motor and matching KB Electronics control board..

 

[DavidR8]

That’s awesome, I’m glad it was an easy swap!

 

[historicalarms]

technology moves along.

yup... the 2 hp ( converted from overhead belt drive to electric in 1930's) on my old lathe is 1/2 as big as a barrel and prob 300 lbs

 

[TorontoBuilder]

Well thanks to DavidR8's surplus motor, my little 10x22 is sporting some new found power, a few images.

The first image is the interesting one, the 2HP BLDC motor is smaller than the original 1HP brushed, technology moves along.

More or less a bolt in, same flange dimensions, Needed a pulley for the larger shaft 14mm vs. 12mm. Made a new control panel to squeeze in the E-Stop.

So now I have a surplus 1HP motor and matching KB Electronics control board..


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that's a great upgradeI love brushless motors. What controller are you using with this @slow-poke ?

and where could one purchase such a motor @DavidR8 ?

I'm going to buy a 706 for a els conversion, and I'd like more oomph to it. I already have the tool post and holders, and other accessories

 

[DavidR8]

that's a great upgradeI love brushless motors. What controller are you using with this @slow-poke ?

and where could one purchase such a motor @DavidR8 ?

I'm going to buy a 706 for a els conversion, and I'd like more oomph to it. I already have the tool post and holders, and other accessories

I bought mine with a mill attached to it

Knowing what I know now, a DC motor and a DC controller from e-motors direct would be the way I would go. That was the way I was originally going to go on my CNC mill conversion thill I decided to go the AC servo motor route.
That's also a viable route but I'm not sure controlling it would be as straightforward as a BLDC motor. Perhaps @slow-poke or @jcdammeyer can chime in on non-CNC ways to control an AC servo motor.

 

[TorontoBuilder]

I bought mine with a mill attached to it

Knowing what I know now, a DC motor and a DC controller from e-motors direct would be the way I would go. That was the way I was originally going to go on my CNC mill conversion thill I decided to go the AC servo motor route.
That's also a viable route but I'm not sure controlling it would be as straightforward as a BLDC motor. Perhaps @slow-poke or @jcdammeyer can chime in on non-CNC ways to control an AC servo motor.

I have an electronics guy, I'll ask him for ideas and see if I can integrate it into either rocketronics or our machining calculator. I like the variable speed idea since I envision adjusting speed based on work piece diameter and material.

 

[slow-poke]

The particular servo motors I'm using rely on simple step and direction pulses just like a stepper. The lathe has integrated drivers, and the drivers for the mill are larger and separated from the motor.

The CX706 is a great candidate for an ELS conversion, for one thing there is a cavity below the spindle that is a perfect size and a great location for a stepper or servo to drive the leadscrew. As soon as you remove all the thread cutting gears etc. lots of space. One very simple bracket to mount the stepper then 3D print the encoder mount and gears and Bob's your uncle. It's a one hour job for the mechanical aspect. The Clough 42 videos are excellent full credit to James for sharing his work. I like to tinker with electronics so I made a "fancy" touchscreen for my ELS that eliminates the need for the TI board and provides flexibility to add more capability, Ease of thread cutting is great but don't overlook the ability to tweak feed speed independent of spindle speed in tiny increments with just a tap up or down, I use that feature constantly.

 

[Susquatch]

Hey @slow-poke, just thinking about your motor upgrade. If you are increasing the horsepower so much, it might be a good idea to program the VFD for a gradual spin up to avoid overtorquing the gearing more than design. I'd aim at something like 20% faster than as built for the highest speed. Or if you have any reason to worry about it, then same time as built.

That will feel slow at the lower speeds, but you can watch it spin up knowing your headstock loves you for it!

 

[slow-poke]

Hey @slow-poke, just thinking about your motor upgrade. If you are increasing the horsepower so much, it might be a good idea to program the VFD for a gradual spin up to avoid overtorquing the gearing more than design. I'd aim at something like 20% faster than as built for the highest speed. Or if you have any reason to worry about it, then same time as built.

That will feel slow at the lower speeds, but you can watch it spin up knowing your headstock loves you for it!

Good point.......

This is actually a BLDC motor with the original Weiss driver board.

I have this setup for two modes: manual and CNC, I need to make a point of turning the pot down when in manual mode.

I'm actually more concerned with de-acceleration back EMF, especially if I hit the stop or E-Stop at high speed. This is one of those I guess I will see what happens, hopefully the driver board has some form of over-voltage protection. The board design is similar to say a KBIC motor controller (focus on minimal components / low cost) in that they are not isolated from the MAINS. Makes for a bit of a PITA when interfacing to CNC controllers that are typically running close to earth potential, because of the large common mode voltage on the motor controller board. I actually found the factory MAINS wiring on this board rolled, so as factory wired there was 120Vac WRT earth on the common of the control inputs. I rolled the H&N to match the factory wiring diagram so the 120Vac is closer to N, however the common mode DC is still nasty. Fortunately I'm using a MESA card and their analog output is fully optically isolated because MESA knows and does things properly For the F/R. On/Off etc. I'm using small relays to interface to deal with the MAINS voltage and high common mode voltage issue.