Need help selecting CNC controller

[pab]

I am new to CNC machine control and would appreciate advice and suggestions as I select a cnc machine controller. The machine is a 3 axis, and in the future 5 axis, router with a 4ft by 5 ft xy table and 30 in Z axis. It will have a 9hp spindle motor. The plan is to to do contour machining of larger parts in softer material. I have been told to look for a controller with has the capability to do similtainious interpolation on all axes and has high block process speeds, and look ahead capability. I am not looking for a high end solution but more moderate cost effective option with good technology. I am also open to suggestions on matching motors and drives.
Thanks for any suggestions you might provide.

[marting]

Hi Pab, welcome to the forum. I will be using Rutex drivers and servo motors for my cnc and I too have in mind to work with 3 axis and switch over to 5 axis. The thing is that the type of driver cards that I have only accept servo motors only which are a bit expensive compaired to stepper motors, but I beleave that Rutex have developed driver cards that accept steppers as well, the only thing is that their mother board only handles 4axis but one could have 2 mother bords and and 5 driver cards. You will then end up with 2 printer ports to connect the driver cards and naturally have to add another 1 or 2 to your PC. Their address is http://www.rutex.com and the only affordable software I have found that could handle 5 axis is Mach 2 and if not mistaken has the ability to conigure the printer ports, inwhich case will be using 2 for 5 axis. I'm not quite sure if this is the kind of setup that you want, however always consult with the suppliers to guide you through as I too am new in this field. As regard to other CAM software I guess one has to pay a good amount of money in order to handle 5 axis.
I hope I have been of any help.
Regards

[ViperTX]

pab,

What you are looking for is not common for this forum, but some of the members work with commercial CNC equipment and can probably offer some pragmatic advice. At the low-end commercial you might check out Ah-Ha Software they are somewhere in the Minneapolis, Minnesota area.

[Al_The_Man]

The machine is a 3 axis, and in the future 5 axis, router with a 4ft by 5 ft xy table and 30 in Z axis. It will have a 9hp spindle motor. The plan is to to do contour machining of larger parts in softer material. I have been told to look for a controller with has the capability to do similtainious interpolation on all axes and has high block process speeds, and look ahead capability.

What exactly is the softer material, as it looks like you describe something between a mill and router table, 9hp spindle with 30" travel in Z. will mean unless the machine is a rigid gantry mill, you will be hard pushed to do even Aluminum IMHO.
There was a Beautifull small gantry mill listed on ebay a few months ago, listed for just over 1k with no takers.
There are quite a few PC based controls that would do the trick, both DIY and commercial, unfortunately to get what you describe is not going to be cheap unless you pick up something like I described above.
Al

[Torsten]

Going with more then 4 axses will limit your choice of controller software
there are three I can think off.

Emc - Linux software - 6 axes
Turbocnc - Dos software - 8 axes
Mach2 - Windows software- 6 axes

Another limitation is that Lpt controllers can only address 4axes per call on a
step and direction controller this means two calls are needed to controll aditional
axes wich will cause a speed penalty.

Also Cam Programs for 5 axes will get expansive.

[ger21]

I don't think there is any speed penalty in MACH2 with 6 axis? Art's website says 6 simultaneous axis' @ 45,000 Khz. I think you do need 2 ports for the 6 axis, but it's not any faster if you only use 3 axis.

[Torsten]

I don't think there is any speed penalty in MACH2 with 6 axis? Art's website says 6 simultaneous axis' @ 45,000 Khz. I think you do need 2 ports for the 6 axis, but it's not any faster if you only use 3 axis.

Just try out.
You do not have to have anything connected to the ports to try.
Just configure it for 6 axes using settings that will get you close
to the limits it claims.
You can configure 6 axes on one lpt port using step and direction.
But it requires 2 calls for the software to drive them all.
I do not know the details of mach2 programming there are some
variations on how to process the steps.
In Turbocnc the number of axes assigned will have a great impact
on the workload imposed on the cpu.
A very clever design in my opinion it will determine the number of
checks required by how many axes are assigned.
The math required for more axes will be more strain on the cpu where
the requirement for the second call will depend on other hardware.

[marting]

Hi Pab, have you found anything that could get you somewhere with your queries about 5 axis driver cards and software? When you said "plan is to to do contour machining of larger parts in softer material" what precision do you have in mind? cause with 30" over hang you realy need a rigid gantry to minimise variations.
Regards