[stampsm]

So I would like someone to critique my plan before I pull out the credit card and start buying parts. I think I understand how everything would go together but I just want to check. I currently have an older Taig mill that has a parallel port control box EMC-XYZ-BX. This apparently was bought as a complete setup from the company EMC-XYYZB-BX CNC Machine Tool Motor Controller for XYZ Tables and Machines by the original owner and has passed more than one hand to finally get to me.

When the mill made it's way to me it needed some TLC and a way to interface with a modern PC. I am thinking the UC400ETH would work great for this application. A question I have is about interfacing a spindle motor to the system. The person who sold it to me apparently had an incorrect motor when I got it so I will likely need to buy a new motor anyways as the pulley does not fit on it and I am worried it might be incorrect in other ways such as not rated for continuous usage. After reading about the ability of the controller to do rigid tapping and speed control I am thinking I might as well upgrade to a better motor in the process. My idea is to use a surplus 90v DC 1/3-1/4HP spindle motor paired with a DG4S-08020 DC servo drive or DG4S-16035 DC servo drive. from what I am understanding this should give me spindle speed control from uccnc and also use the rigid tapping features?

I do have a bigger mill with a close to 1HP motor being stored right now so overbuying better parts I can pass along to another machine in the future is something I might consider.

[robertspark]

Short answer.... yes the uc400eth will work great for your application, and best to use UCCNC imho.

Please consider that both ports on the uc400eth are LPT equivalent pinout ports..... whilst this may not be an issue or obvious, it means that both ports have exactly the same pinout (ie. each port can ONLY have 5 inputs, you cannot change the outputs to inputs as can be done with some motion controllers which use what appears to be a 26 pin IDE connector in a multi LPT configuration.

So, you can only have 10 inputs in total, but 26 outputs on the uc400eth.

Can't answer the spindle question, you may be best to ask in a hardware section of the forum with more hardware viewers as its a more generic question and not uccnc specific.

[vmax549]

To add to what Robert said. The UC400 has 2 ports that are LPT1 type ports. Other controllers use 1 lpt1 and 1 lpt2 type port configs . What does that really mean ? not much but you do have to be aware of where you wire your I/O .

(;-) TP

[stampsm]

So I need to count my inputs and outputs it seems. It does seem 26+10 should be adequate with a few inputs to spare.

my controller box seems to use every single one of the pins from one port so I have 13+5 for anything not controlled through the EMC-XYZ-BX. The main reason I was looking at the UC400ETH is the 400khz vs 100khz for the USB models. For normal stepper motor travel this doesn't seem to be a major issue, but I though I might need it for spindle servo control. If I have a 1000 count per revolution encoder going 3k RPM it should produce feedback pulses at 1000(pulse per rotation) x 50(rotations per second) this hits at 50k per second. from what I was reading there needs to be a clear distinction between pulse and no pulse from the encoder so a ration of 1:1 at 100k sample rate seems a little close for comfort.

Maybe I am reading a little to much into this and going for a device overpowered for my needs? Is a encoder resolution of 1000 per rotation overkill and I can drop to lets say 500 and have plenty of margin for using the UC300-5LPT?

[vmax549]

An ideal spindle encoder would be 100 ppr or as quad 400cpr. Also a TAIG is not going to have a lot of extra torque for rigid tapping.

Just a thought,

(;-) TP