It's also worth mentioning for those who look at this thread for feedback on the parts I've used like the dspmc/ip and the a-m-c amplifiers...this machine is really purring now.  If you are considering going this route you can expect good things.

Thats good to hear that the DSPMC is working well. Its analogue capability is something that has been needed for a while in Mach
Hood

Here's a multi-purpose picture.  You can see a number plate for a yacht I just machined.  I  both pocketed out around the letters/numbers and profiled around the letters/numbers in 5 successively deeper passes at 57 ipm.  Each pass matched the last perfectly so I think that's pretty good proof the dspmc is up to the task.  I also only have to zero the z for any job; Since I use the index pulses to home the machine  it homes acurate to half a ten which I guarantee you is better than i would do setting up each job.  I just keep the corner of the vise saved as my main fixture and when I throw something into it all I have to do is zero the z with feeler gages.  I have a square atlas 4 jaw scroll chuck I used to have mounted on the table and saved as my 2nd fixture but it was in the way of machining this number plate so I will have to set it up again next time I do something I want to work from the center on.

You can also see the troyke nc10a 4th axis I just broke down, refinished, and have half way reassembled.  I already installed the amc amp and wiring to the dspmc in the control box when I set up the other 3 axes.  Now I need to finish putting it together, machine a mounting plate, and set the thing up.

great thread. thank you so much for sharing this journey. good read. i work on the opposite side of the spectrum to you with most my jobs happening inside of one cubic inch so its always great to see other people using their tools.

Regards
Chris

Thanks Chris,

Speeking of wanting to machine big stuff, I've stalled my spindle a few times and have decided I need more power.  I had gotten the electronics to count spindle rpm a while back but never got around to installing them.  Now I won't have to.  I just bought a fanuc 20s servo to replace my spindle motor.  It's a 4.7hp servo with a 2500 pulse coder on it.

Pico makes a converter to pull fanuc's proprietary commutation signals out of their pulse coder signals to give standard hall and encoder signals.  I'm getting one of these: http://pico-systems.com/oscrc4/catalog/product_info.php?cPath=4&products_id=29

I also ordered an a-m-c b30a40ac amplifier.  It takes AC input so I'm not limited by the dc power supply I have running my positioning axes.  I'll be able to scale the gain to get the 2000 rpm max motor speed at 146v and run 15 amps continuous 30 amps peak.  The motor's stall current is 20 amps.

This aught to let me take much deaper cuts with big face mills, easily and acurately control spindle start up and rpm with the normal gcode, perform semi-rigid tapping, and since it has spindle orientation I can implement a tool changer if I decide to.

AMC have just launched a open forum for support questions.
www.a-m-c.com/forum.html
Nosmo.

Very nice setup! well done.

just a word of warning about expanding-sheave drives like that, we took an XYZ drive apart a few years ago and the spring leapt out and smashed a big chunk out of our workshop wall. Best to be careful Obviously you've got away with it so fair enough.

It's also worth mentioning for those who look at this thread for feedback on the parts I've used like the dspmc/ip and the a-m-c amplifiers...this machine is really purring now.  If you are considering going this route you can expect good things.

can/would you provide links to the exact parts you used. minus the spindle.
Thanks
archie =) =) =)

I've been seeing a lot of a-m-c sinusoidal drives for sale.  Does anyone know of an inexpesive/reasonably priced means of generating the sinusoidal control signal those drives require?  Rufi said the dspMC can't do it so I'm wondering if there is something I could put in between to do the job.

The problem is the plain S series require two sinusoidal command signals with 120° phase shift between them.
Probably a sine wave output oscillator that uses the digital step frequency to synchronize it would work.
It should be fairly simple circuit, but I know of nothing out there off the shelf.
N.