You may want to also consider the Encoder module and the MPG module if you go with the IP-A.
It will add to the cost but it will allow you rigid tapping if you ave the Enc Module and If you have the MPG module it will allow you to have a MPG on your panel or have a hand held pendant.

Hood

Ooh, goodies, goodies, goodies

Looks like either option is around £100 so not a killer.

Issues I see would be getting the encoder mounted to the Bridgeport spindle for the threading unit - there is no clear access to the spindle really, the top is clear for the drawbar wrench and there is little below really, the motor spineless no good as its belt drive and vari-speed. Will need more research here I think, but these look like easy add-ons later.

The Enc module will also allow you to make a Tool Height Setter like I have, very useful for setting up tools off of the machine

Hood

Getting ahead of myself now, does it come with a built-in ATC

Seriously though, this is looking more and more like a project now

Even adding the high-speed spindle as a second Z axis OR as I have seen done, adding it as a clamp-on fixture to the main Z axis. This has big benefits for me as it means I only need one machine for all tasks from heavy milling to fine engraving.

Ha ha afraid not but even without an ATC the heaight setter is handy, have one for the Beaver NC5 as well, set up all tools I will be using for the job and then when it comes to a tool change machine moves to a position, switches spindle off and I press the power drawbar button and swap tools and then press Start and off it goes

Just to add a bit, the ESS is reasonably cheap but by the time you add things such as spindle control board, differential boards for Step/Dir, one or more breakout boards, boards for conversion from 5v to 24v and vice versa  for the I/O then the cost rises quite a bit and ends up getting close to the CSMIO.

Hood

Yes, i'm pretty much sold on the CSMIO/A direction now

Pricing it all up.

Looking like..

Converting my machine,
750w servo motors,
CSMIO/A control
3:1 reduction on all axes.

With the 5mm pitch screws I think that gives me 5000mm/min rapids and 0.0006mm resolution - silly on an old Bridgeport

5m/min if the motors are 3000rpm ones.

Hood

Yep, got it - pretty fast for an old machine i think, will have to service the lube system while I'm in there.

Will be fine as long as lube is ok. My Beaver NC5 is an old machine as well, similar setup to a Bridgeport and it does 8m/min no probs. Had it at 10m/min for a bit but just thought it a wee touch fast for it so dropped to 8.

Hood

Control options...

Not sure we need a alpha keyboard for a mill, hows about a touch-screen monitor to do away with the mouse and a small numeric USB keypad?

Or

normal monitor (cheaper/stronger) and a track-ball and numeric keypad?

Looking at controls..
X/Y joystick
Z joystick
Knee up/down buttons
Speed override knob
Feed override knob
Cycle start
Feed-hold
Stop


Spindle motor...
This is currently run from a VFD but only at 50Hz, the head is the vari-speed unit with back-gear so i have 50-3000rpm but in two ranges and manual speed control. Whats a good option here - using the VFD won't address the variable torque ability of the vari-speed unit so can't just lock it in one spot.

Any cool options here to play with?

With a bit of fiddling the vari-speed changer could probably be motorised with a stepper and gearbox, not sure it's worth it?

Mach can obviously take over the Fwd/Rev function - still using the old switch but I wired it to the VFD so I can plug-reverse for tapping;) That was before i got the tapping head.

Any cool ideas?