Weiss VM32 CNC conversion

[DavidR8]

I've been toying with the idea of building another CNC machine. Namely a CNC mill.
I have my CNC router which is amazing for wood and even aluminum in a pinch though the high speed spindle is bit of a challenge. And steel is pretty much a non-starter.
My Weiss VM32 mill, same as a CX601/PM30 is a conversion candidate but I wanted to retain some semblance of 'manual' control to do simple operations like facing or side milling without having to do CAD/CAM.
Spent two hours with a local member of Canadian Hobby Metal Workers (the CDN version of HM) last Sunday talking CNC, steppers, servos, control software etc.

Had a lightbulb moment when John set up a facemill and quickly surfaced a block of aluminum using simple commands into the MDI interface on LinuxCNC.
That was was the part that I was missing; how to do a simple job like that without being able to turn handwheels.

Called Dave at ArizonaCNC as he makes a kit for my mill. Doublenut ball screws and all the motor mounts for three axes. Not cheap at over $1000 USD/$1400CAD. And I'd still need stepper/servos, power supplies etc. But nothing ventured, nothing gained right?

Figured I'd give LinuxCNC another shot since I have a spare PC.

While searching for servo motor spindle motor conversions I ran across a post on Canadian Hobby Metal Workers for the following:

-Masso G3 controller and pendant
-3 axis Arizona CNC kits CX601 conversion kit, machined for:
-DMM servo motors x,y,z axis(z axis has brake). Includes the cabling for motors/encoders/setup usb cables
-DMM AC servo drivers x,y,z axis
-Meanwell power supplies, filter, capacitors, breaker
-Spare R8 spindle with belt drive pulley
-some other parts, oiler, fasteners, air cylinder for toolchanger, (see pics)
-Toolchanger and belt drive was never completed, so all of this was never used or installed.

I immediately contacted the poster, and we struck a deal. $1400 CDN plus $94 shipping.
Parts are on their way as I type.

 

[DavidR8]

After some monkeying around I have movement on one motor.
Was pretty flummoxed yesterday because I could not get the axis to move.
Turned out that setting the motor: distance per revolution to 10mm meant that I couldn't detect to motor spindle turning because the resolution was too fine.
Changed it 1mm and voila, I can jog the motor via the keyboard or MPG.
Happy Days!

On the slight downside, the 48V, 20A power supply has the loudest fan this side of a Harrier jet.

Confident that I'll be able to sort out the magic pixies side of the conversion, I started tearing the mill apart.
Pulled the table off and the Y axis carriage (no idea if that's the correct term.
Ran into the first snag: the bolt holes in the front of the machine don't match the motor mount assembly from Arizona CNC. Not the fault of the kit rather some crappy assembly at the factory.

Two of the four cap screws will engage in diagonally opposite holes. The misalignment is so slight that I can't drill new holes for the holes that don't match when the mount is in the proper position.
I can get nuts on the bottom two cap screws but not the top two because they are too close to the bottom side of the casting.

I have some 12mm aluminum plate that I could use to make an adapter plate that is bigger than the mount, bolt that to the front of the base then put the mount on the plate but I don't know if I can spare the 12mm of length on the ball screw.

 

[DavidR8]

After a bit of noodling I think I have a solution. The upper right cap screw positions the mount in the right vertical orientation relative to the Y-axis table.
If I through drill the two bottom holes and put nuts on the inside that should be plenty secure.

 

[DavidR8]

More progress today. Basically have to disassemble the mill to install the ball screws.
First I made a drill guide to shift the mount holes in the casting.


That worked out well so I turned my attention to taking the head and the column off so I could install the Y and Z axis ball screws.
I don’t have pics of removing the column as it was very difficult to do.
There’s a gas strut in the column which was a complete pain in the rear to remove because unlike gas struts on a trunk for example, the strut couldn’t be popped off the ball. So I had lean the column back so I could unscrew the lower ball about 1/16 of a turn at a time for the length of the 1” stud.

Once off I tried to slide the Y axis ball screw into place.
No dice as the base casting prevented the end from going all the way through the hole in the front of the base.
Break on the angle grinder and cut the opening an inch longer.
Dressed the new cut with a file and now the ball screw can slide into place.

With the ball screw in place I put on the mount which contains two bearings for the driven end of the ball screw.
Mount fits perfectly on the shaft but the hole in the front of the casting isn’t large enough for the ball screw to drop down enough for the mount to match my up with my newly drill holes in the casting.
Off to Home Depot to buy a 1.25” hole saw to enlarge the hole.

With the hole enlarged it was easy to put everything together.

And the column is back on. That was a thrash.