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Posted: Sun 06 Aug , 2017 17:28 pm
by robertpearce4
Hi guys, Is there any historic information or a technical overview for the TRIAC/VMS miller including key component changes/update, types of servos used/variants etc? I have aquired just the miller half plus the monitor and was hoping I could build a user friendly controller. It seems so sad to scrap it. I have read various upgrade post but in most cases it assumes the orginal controller is available. Please help

Re: Newby

Posted: Fri 11 Aug , 2017 22:20 pm
by Lone_Ranger
Hi Robert

Not too hard to build a new controller, yes, you do appear to have the "Big Black Box" missing that has all the Motion Control system, power supplies, stepper drives and various fuse holders and relays etc, all the bits required to make the machine move :D

OK, you will need a decent size cabinet to house all your bits and pieces for starters but that actually may be the last thing to buy, get everyhting else first then you will know how big a box you need :D
A computer, couple of options here, either an outside free standing PC (There are some Quad core PCs on Ebay for around £90 that will do the job, or a smaller box inside your big one that you can fit a small modern Motherboard and SSD (Solid State Drive) inside, that way everything is in the main box.
A suitable power supply for all the control equipment (Motion Control Card, Relays etc) usually 24Volts x 2.5 Amps will do it.
Various relays to switch on/enable stuff like the Coolant pump and the Spindle drive. Not expensive :)
3 x stepper drives one for each axis and a power supply for them, again not expensive :)
A motion controller, a pretty good one is the CS Labs CSMIO IP M which is a relatively cheap industrial strength controller that uses 24Volts control voltage so is better for reducing any interference and the controller connects to the computer via Ethernet (CAT 6) cable which gives a fast connection speed and also is virtually interference free.
Some control software like Mach3 or Mach4, I have used both and I have found that Mach4 which is the latest and has been developed for Industrial use is the better of the two, difference in price is only about $21 USD.
As you have an Automatic Tool Changer on the machine there are again a couple of options, if using the Mach3/4 software you can write or get from the Forums a Macro (Small program) that will step the ATC to the tool required, or you can buy a smal PLC (Programable Logic Computer) that you can use to operate the ATC, a good little inexpensive one available from Radio Spares (rs-online) is the BARTH STG 600 which is about £90 on a next day delivery, you can get all your relays, fuse holders etc, etc, etc from them as well, I use them all the time :)
You will also need a drive for the Spindle Motor, on the Triac that is usually an SEM DC Brushed Motor and the drive that Denford usually fitted for that motor was a Sprint Drive from Sprint Electrics, they still make the drives in a more modern format and they are properly Isolated unlike the older ones, I bought one earlier this year for a Triac direct from Sprint Electrics and it was only about £200 if I remember correctly, I can send you some photos of the one I did from scratch and of one I am currently updating/upgrading to modern electronics and Motors etc !!

If you want any help with this project then fire me a PM via this message board and I will let you have a `phone number and I am happy to chat !! :) :)

P.S. A tip, please reduce the size of the images you upload, it is a right pain scrolling sideways to read stuff :D :D

Hope the above is of some help to you ! !

I have done a full control system on a Triac from just the bare casting, took a while, months of a job, nice Winter project for you :D :D :D


Re: Newby

Posted: Sat 12 Aug , 2017 17:34 pm
by robertpearce4
Hi Lone_Ranger,

Thank you for taking the time reply. I now need to throw a bit of a spanner in the works. After asking the previous owner what actually happened to the controller (and sending a picture of the box), I now have the controller. It appears to be complete and in fare condition. The floppy drive front is damaged, but I have one from an old PC if required. There is no software, only a circuit diagram inside. I assume the original Denford supplied S/W was loaded at power-up from the 1.44Mbyte boot dos disk? To initially use this miller as a training machine for myself, what would be required to get milling? I assume there was some Denford specific files (Licence, S/W Key etc), CNC Interpreter/Application (Mint?) S/W, initialization files and the miller working program (if required). I guess I'm now asking how best to implement your Mach3/4 software upgrade suggestion, using as much as the original hardware with as little hacking as possible. What is the advantage of an isolated spindle drive over non-isolated? Does powering the spindle motor from an isolated LV transformer do similar? I hope the 2 photos included are smaller. I have reduced the file size.

Re: Newby

Posted: Sun 13 Aug , 2017 21:35 pm
by moray
If you want to try the absolut minimal approach, download the DOS software from the denford site, copy it to a floppy, and see if the machine powers up and loads the software.

Barebones conversion would be Mach or LinuxCNC via parallel port with a 24V capable breakout board (or two - one probably won't have enough inputs for the ATC).

Next option is to add a motion controller, where options vary from reasonably cheap to fairly expensive.

Regarding the spindle, they originally used an SCR style drive, which means the control wiring is at near mains voltage. You have to ensure you use a fully isolated 0-10V control source, otherwise something will release magic smoke.

Re: Newby

Posted: Sun 13 Aug , 2017 22:22 pm
by Lone_Ranger
Great, you have the big box so forget everything I wrote before :D :D

Contact Denford with the Serial numbers of your machine as there may be a little difference in the software for the 8 pot tool changer like you have and the 6 pot one. Probably just a parameter change but small things like that can easily stop a machine from running properly:D

Then like the previous poster said try firing it up, the blokes at Denford do watch this Forum so may jump in on this one for you as well :D

Good luck :D :D :D

Re: Newby

Posted: Mon 14 Aug , 2017 21:03 pm
by robertpearce4
Thanks for your support guys. I have sent a S/W enquiry request to Denford. There appears something scary (possible malicious code hyperlink) on the S/W part of the forum if you follow the trail. I will let you know how things progress.