Retrofitting an Older Light Machines CNC Lathe

[brainstatic]

Hello All,

I purchased an older, cerca 1984, Light Machines CNC lathe with power supply and controller. It was surplus from a state university, and like brand new with many accessories. However, without the original Apple IIe computer to run the lot, I am left trying to connect the machine to a modern computer.

Has anyone out there in CNCzone been able to do this, or is my only option to upgrade the whole system?

It stands to reason that if I can identify the proper wiring, what does what, I could just rewire and go... Maybe???

I have tried to contact the OEM for a wiring diagram, or adapter of sorts, yet they have not been able to help me.

Thank you,
Brainstatic

[ghynes]

Hi There,

Saw your post and thought I would drop a line. First off I do not have an LM lathe (but I do have an LM TMC-1000 CNC mill!) but I have retrofitted a similiar type lathe to modern CNC. My lathe is a COLNE 5C from the mid 80's and the electronics was old and archaic. Size wise this is slightly larger than yours which is I beleive based on an early SHERLINE Lathe, whereas mine is about the size of an EMCO 5. I swapped out the motors for some modern PACSCI bipolar units, replaced the stepper drive with a modern unit fropm XYLOTEX and to have computer control of the spindle speed and direction I used a Bob Campbell Combo breakout board. Added a spindle indexing opto sensor and bob's ur uncle. I run it under MACH3TURN and have been very pleased thus far. In fact I just this evening did my first successful CNC threading of a piece of 1/4" aluminium rod. I know it's not that hard to thread a piece of rod with a die (probably faster) but it was neat to try and know that it works.

You will not be disappointed with any of the components I mentioned above. The quality and service from the respective suppliers is excellent! I also use a XYLOTEX controller on my CNC router and will at some point also convert my TMC1000 to a 4 axis xylotex to get it running under MACH3 as well.

Your Lm set-up, to be complete, requires a separate black control box as well as a slotted PCB card that goes into the computor. As well there are cables that run between the two units and as well to the lathe. Another option for you might be to watch ebay and buy a complete stock controller for this machine as many show up there after conversions are done.. They do have DOS/WINDOWS based hardware-software. The PC uses a slotted circuit board to interface with the black control box, you may be able to get the software for free from Intelitek which still makes these products however the circuit board for the pc is fairly expensive maybe about $500 and there were several versions. I have an older EISA bus style card and it requires an ancient PC wheras the newer cards are PCI bus which modern PC's still have. I run my LM under Win95 and got the software (free) by e-mail after a request to the service dept. It actually works excellent and I like it but will upgrade at some point to standardize all my machines on MACH as as well to get a 4th axis on my mill which the factory software doesn't allow!

Good luck

Cheerio
Gerald

PS If you are interested to see a few pics of my conversion feeel free to drop a line direct to ghynes@mts.net and I will email them

[theobean]

Hi,
Im new to this CNC forum and I also dont have the lathe that you have but I have the Colne 5 that Im trying to repair with a view to connecting to a computer. the interface i reckon maybe similar to yours its an IDC plug similar
to whats inside a computer. on looking inside at the circuit board connected
to the interface plug you can identify by following the tracks to I.C chips that have numbers on them such as 74LS125 ,7403,etc you can then identify the one that the interface plug connects to and look it up on the internet if its not a serial decoder driver or serial to parallel data converter then your interface is most likely a parallel input which would/could be connected to a parallel port on a computer. However I strongly advise making a simple buffer board circuit see old electronics projects as inputes and outputs from your lathe firstly need to be connected correctly and voltage levels on newer computers are not the same as older ones. I have seen some freeware CNC software that Im investigating that interfaces with a parallel port on a computer. A lot of if and buts only attempt if youve got time and no money
to waste.
Anyway if anyone out there has circuit diagram for the Colne 5 please email
me even a picture of the circuit boards with the ribbon cable header on the
small board maybe handy sorry not trying to hijack you post.

[backyard_cnc]

theobean,

Check out this UK firm for a plug and play retro for a COLNE 5. I opted to swap all the electronics in my COLNE 5 for new stuff but this is certainly another way to go! I wonder if your lathe is currently working and if so what sort of backlash you are experiencing in the ballscrews? I find mine to be quite loose and this backlash causes issues when threading in particular

Gerald

http://www.eaziform.co.uk/index.php?products,cncupgrade

[Mark5615318]

u can try changing the ballscrew parameters a tenth at a time, they comp. for wear, digitaly