[rabler]

Hello everyone,

I'm looking for feedback on buying a Tree 750 VMC as a machine to retrofit with a more modern controller. There is one in my area that has been available for about a year from someone who bought it as a machine to use for a business idea that didn't fly. This machine as shipped uses a Siemens Acramatic 2100 MC controller, a Yaskawa 626VM3 drive for a 15HP spindle, and Yaskawa Servopack SGDB-15ADG axis servos, and a 20 tool ATC. Documention is available for these. The machine is currently throwing an alarm, which the current owner attributes to running it off of an undersized RPC. Obviously that could be the issue but bears investigation. I'm not set on a particular controller path, but lean a bit toward LinuxCNC front end, Galil or Mesa controller card, but am exploring a few other options based on various suggestions.

1) Has anyone retrofitted a similar machine that has feedback?
2) Does anyone have thoughts on the Yaskawa servos and possibility of reusing those?

I'm retired, and looking to do this as a hobby obviously. I have fairly extensive experience in electronics and embedded computers, but not in the industrial automation/cnc machining. This would be a way of challenging myself toward something new. I have fairly decent manual machining capabilities in my shop, and expectations that this will be a project of several years. Seems like a path more to my inclinations than CNC converting a new import benchtop mill, lol.

[Al_The_Man]

If you can get the present system going, it will have the edge over the others, I retrofitted a couple of XLO knee mills which are about the same size.
At the time i used the Acroloop Motion card which did a very nice job. Unfortunately they were taken over by Parker Motion and i lost touch.
I have also used the Galil cards which are also nice
It should be easy to diagnose where the error is coming from.

[rabler]

If you can get the present system going, it will have the edge over the others, I retrofitted a couple of XLO knee mills which are about the same size.
At the time i used the Acroloop Motion card which did a very nice job. Unfortunately they were taken over by Parker Motion and i lost touch.
I have also used the Galil cards which are also nice
It should be easy to diagnose where the error is coming from.

Definitely, reviving the current system makes sense to explore. But I'm also considering worse case scenario as I'm not paying for a working VMC.

[Iron-Man]

Hello Rabler

The Yaskawa servos { SGDB-15ADG } can be run in velocity, torque or step-direction mode. You can use Mesa Cards, Linux CNC, or Path Pilot. There is a learning curve but there is great information at CNCZONE or at LinuxCNC.
I converted a Denford NovaTurn to Yaskawa servos. The servos run in torque mode with analog control +- 10V using Path Pilot. The system is completely closed loop.
My set-up, AMD GizmoSphere, IBOB2, Mesa 7i77, 6i25, Yaskawa SGDA 01AS, Path Pilot. https://www.cnczone.com/forums/bench...754-cnc-2.html


Hope this helps,

Iron-Man

[joeavaerage]

Hi,
my research suggests also that the Yaskawa servos can be used in velocity, torque AND Step/Direction modes. This last mode means yoiu can use a wide range
of controllers including Mach3 or Mach4, UCCNC, PlanetCNC, Centroid Acorn etc. All of these controllers are very modestly priced and all Step/Direction types.

The servo is still closed loop, but instead of the control loop being closed by the motion control it is closed by the servo drive. This method is very effective because
its the same manufacturer (Yaskawa) that makes both the servo and the drive, and the closed loop combination thereof is very good indeed, easily the match, and maybe even
better, than the same servo loop being closed by the motion control.

Craig

[rabler]

@Iron-Man, @joeaverage
Thanks for the feedback. Makes sense that step/direction would be easy to implement. Hadn't dug that deeply into their setup so good to know. Will be looking at the machine again later this week.

[servtech]

Hello everyone,

I'm looking for feedback on buying a Tree 750 VMC as a machine to retrofit with a more modern controller. There is one in my area that has been available for about a year from someone who bought it as a machine to use for a business idea that didn't fly. This machine as shipped uses a Siemens Acramatic 2100 MC controller, a Yaskawa 626VM3 drive for a 15HP spindle, and Yaskawa Servopack SGDB-15ADG axis servos, and a 20 tool ATC. Documention is available for these. The machine is currently throwing an alarm, which the current owner attributes to running it off of an undersized RPC. Obviously that could be the issue but bears investigation. I'm not set on a particular controller path, but lean a bit toward LinuxCNC front end, Galil or Mesa controller card, but am exploring a few other options based on various suggestions.

1) Has anyone retrofitted a similar machine that has feedback?
2) Does anyone have thoughts on the Yaskawa servos and possibility of reusing those?

I'm retired, and looking to do this as a hobby obviously. I have fairly extensive experience in electronics and embedded computers, but not in the industrial automation/cnc machining. This would be a way of challenging myself toward something new. I have fairly decent manual machining capabilities in my shop, and expectations that this will be a project of several years. Seems like a path more to my inclinations than CNC converting a new import benchtop mill, lol.

The tree machine would be fine so long as you can correctly interface all the existing external servos and encoder feedbacks to the new controller.

There is also the PLC/ PMC program and interface to consider.

Siemens do not support this old acramatic control and haven't for many years.

Good tree wiring diagrams would be essential to do the retrofit successfully.