Does the motor stay powered when locked or does the power get switched off after  it has locked?
What do the optical switches look like physically? are they slotted type?
Hood

the motor stays powered but at a lower voltage, holding it on the pawl. The optical switches look like they are reflective and are OPB 704 and there are three of them.

I am afraid I am not an electronics guy so cant really say how things would connect to the parallel port, would imagine they are outputting 12v at the moment.
Not great at VB but it looks like it should be straightforward as well.

Any idea which optos are for each tool, eg top and middle on and lower off may be tool 1

Does the motor just work via a  relay? In other words when the relay is closed the motor is supplied the low voltage to hold it one way, when the relay is powered then the direction is changed and the voltage is 24v?

Hood

yes the motor is powered forward by 24v, and when the relay is off the motor is reversed and supplied with 12v. I believe this 12v may have been lowered on newer models.
The logic side is called greycode, and i'll try to find a better link for info.

this may help

http://www.denfordata.com/bb/viewtopic.php?f=43&t=1464&p=10777&hilit=starturn+5#p10777

Well I reckon similar to I use in my macro would work fine if you could get the inputs to Mach and have the relay worked via an output. Here is what the first two tools would look like according to that pdf.


If GetSelectedTool=1  Then               
 Do                                       
 ActivateSignal(OutPut1)                 
 If IsActive(Input1) And IsActive(Input2) And  IsActive(Input3) Then Exit Do             
 Loop                                     
 DeActivateSignal(OutPut1)
 End If   
 
If GetSelectedTool=2  Then               
 Do                                       
 ActivateSignal(OutPut1)                 
 If IsActive(Input1) And IsActive(Input2) And Not IsActive(Input3) Then Exit Do             
 Loop                                     
 DeActivateSignal(OutPut1)
 End If 

Hood

Just to clarify, you wouldnt need to use these specific inputs and outputs if you already use them, its just the first ones I chose when I wrote it.

My turrets work via a PLC over modbus but my macros are similar with the exception of each tool just has a single input to Mach as the PLC will put out a signal depending on the switch sequence. My front turret works a bit differently but sort of the same idea

Hood

Hi, I think my toolchanger is the same. I have a Denford Orac. You will need 3 inputs for the opto sensors, be careful with connections as the voltage going to the turret is 24v so you will need some electronics to get down to TTL levels.

I have attached my toolchanger macro that operates my toolchanger, have a look and perhaps Hood could help you make it better as it was my first attempt at macros, it does work I have been using the lathe pretty much every day for the last 6 years but now and again during a toolchange Mach seems to forget which tool it needs and the changer just spins aimlessly until I intervene. I have never sorted that and as it happens only once in a blue moon it is more bothersome than annoying but I would like to know why.

Hope this is of some help

could it be done with two inputs to mach, with a microswitch for tool position one, and eight positions on another micrswitch for the tool positions. You call tool position one first then it knows where it is and can go from there.

is that possible to control

Wow I have had to go out for the day  so sorry for not being here but many thanks for getting as far as we have.
I am not a wiz with electronics but very good at following instructions and don't mind being a guinipig for this as I would love to get it sorted out and working.
Then when the next chap asks we will have an answer for him.
If you want me to do anything or need to get somthing like parts please give me chance as I got made redundent and have been forced on sick when Ireally want to go back to work so right now they are not giving me nothing so I have to find little jobs to cover the cost of bit for the workshop.
But hey if you can tell me what to do I will give it a go and see what gives 
many thanks from the dim whitted owner