Boxford TCL 240 Conversion Project - DIYCNC Optoport V3 & Spindle V4 ??

**clutchslip** · 08-10-2020

Hi all,

I've recently found a Boxford TCL 240 in OKish condition that I plan to update to work with modern electronics and software. I haven't yet made my mind up, but LinuxCNC and Mach3 seem to be two of the most obvious candidates.

So far all I have done is given the machine a superficial clean up and had a look at the electronics section. The version I have has the fold-down tailstock but no auto tool changer carousel, with only the wiring for two motors visible from the front.

The 240 lathe I have has a Lenze motor driven by a Gemini controller. From the research Ive done I had found several references to problems with the metallised paper capacitors and the caps fitted appear to have failed although fortunately no fire damage. The main live feed to the Gemini has been disconnected,. There are signs of some other tinkering inside, the front panel wiring is unplugged from any board connections, the Lenze motor has had some of its feed wiring cut and what looks like a (Zenner) diode placed across its contactor feed connections.

What I also find hiding among the original electronics, very neatly installed on their own board with standoffs, are a pair of DIYCNC boards, with no connections in or out. Obviously a previous owner intended to convert the machine, but it looks like only preparatory work was undertaken.

I have found some info for the Optoport V3 board online, but only for the Spindle V5 rather than the Spindle V4 controller, if anyone has a copy of that I would be grateful.

Neither of the two boards have as yet been wired in, only physically mounted, and it came as a complete surprise to me to find them inside. I am not 'invested' in any way in using either of them, but from what I have read they seem to have been quite well regarded when they were new, even if that is a few years ago now. I would welcome any comments on the use of these boards today and whether they would force me into any one direction that wouldn't be that great for a noob.

Ade

**depronman** · 08-10-2020

Hi
If you are considering say linuxcnc would you be using a parallel port or a Mesa board

It can be done quiet cheaply with a parallel port or better still two of them
Be wary of the lenze spindle controller it can bit you. It is controlled by a 0 to 10 volts input to control speed but this is floating at 110volts to 122 volts
This presents a need to isolate this voltage from the breakout board

On the end of the lenze controller there is normally an isolator board that you can safely attach to the pwm on the break out board this providing the 0 to 10v input to the isolator board and in turn feeds the same 0 to 10v signal into the lenze controller but protects the break out board from the 110v

On my vmc190 the isolator board was none functional so I had to use a board which converted step/dir to pwm but also isolated the lenze voltage it also is a relay to switch the spindle on off

A std BOB with a single relay can be used, the relay is normally output pin 17 and will turn the relay on off under m3 m5 commands. This can be safely connected to the lenze controller. It is only the speed control that is floating at 110v

I would suggest doing some reacher for the stepper driver voltages
I assume you are fitting new stepper drivers and keeping the original stepper motors
Once the voltage is known then suitable stepper drivers and psu can be sourced
As an example my orac lathe as steppers running at 70volts from memory the stepper drivers where around £35 ea and the 70v 10amp psu was about £40
A BOB is around £8

You then need a PC to run linuxcnc. This need not be a particularly modern pc as linuxcnc is not resource hungry like windows
If you can find one with a parallel port then great but think about also adding a pci parallel port card and using both parallel ports
One set to put mode and the other set to in mode
This will provide more than enough inputs
The spindle should have an encoder on it there will
Be two sensors one for trigger measuring each revolution and the other measuring each hole in the disc. Linuxcnc will happily thread cut using these two sensors which is something I could never get mach3 to do
I would recommend you use gmoccapy instead of Axis as the linuxcnc GUI as it is much more like an industrial cnc controller where as Axis is like a computer screen

What I will say is linuxcnc is rock solid and threads where as mach3 would never thread and is not as solid with occasional crashes and lock ups which I have never had with LCNC

If you use pair of parallel ports you will have enough inputs for the eStop homing switches spindle encoder and plenty left over for panel buttons for jog X & Z cycle start stop step etc
You need not know Linux to use linuxcnc

Drop me a pm if you get stuck with anything

Cheers. Paul

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