View Full Version : Anyone converted a Denford VMC 1300 Pro to Mach or LinuxCNC?

11-05-2016, 05:21 PM
I've recently acquired a VMC 1300 Pro and would prefer to use industry std software to drive the brute. I've found other forums with smaller Denford mill conversion advice (using the same NextStep controller). Just wondered if there's anyone UK-based who has experience too

12-05-2016, 09:28 AM
I realise I may have been better posting in the Milling Machines, Builds & Conversions (http://www.mycncuk.com/forums/33-Milling-Machines-Builds-Conversions) thread, where there are threads on Denford conversions

13-05-2016, 12:16 AM
There are plenty people who've converted Denford mills, although I would guess the number of VMCs produced isn't that great, so the number that have been retrofitted will be even less. There won't be much difference in terms of the basic electronics between all the machines using the NextStep controllers.

What do you mean by industry standard software?
There are quite a few options available, some better than others, but it all depends what you'd like to achieve.

13-05-2016, 09:19 AM
Thanks for the reply m_c. I'm thinking Mach 3 (or 4) or LinuxCNC to drive the VMC via a parallel connection to the NextStep "bottom board".

This is my reference data sets acquired from the web so far:

Baldor Nextstep Step and Direction pins - 96way connector

documenting step and direction signals to the Baldor "bottom-board" stepper drives


Second post in the thread has the Pro diagrams - the Pro uses a Baldor Microflex servo control for the spindle drive

Baldor Drive Microflex Installation Manual

this servo control is a real beauty, I've no idea what they cost

Really detailed and well illustrated (with videos) blog by Jay Summet about conversion of Micromill 2000 to Mach 3, a series of 4 posts, starting with X, Y, Z and concluding with spindle speed

Jay's conversion to drive the spindle motor controller via a PWM signal involves some board mods that I'm reluctant to do, so will look for add-on board to get the 10V analogue drive for the spindle speed (I still have to check that the MicroFlex spindle is controlled in this way)

Looking on diycnc.co.uk for suitable BoB and step to 10V converter

13-05-2016, 10:40 PM
I have a converted triac, which is the same size as a 1300 and atc.

Running it in mach3 with machstdmill screen Set, the machine runs a treat.

All you would need to do is take denfords stuff out and put stepper drivers in, breakout board something like a pmdx as the machine has an atc, a spindle v4 board amd a new psu in

14-05-2016, 09:48 AM
Thanks Andy, I was hoping to have a go with the "stuff" that Denford build in, at least initially. There's no ATC on my VMC, nor 4th axis (at mo), but it is the Pro version with the bigger/faster spindle drive

14-05-2016, 07:40 PM
It sounds like you've got a good plan, and found the majority of the required information.

Nothing wrong with trying what's already there. By keeping the NextStep card, you should also have all the required supply voltages already there, as I'm fairly sure the bottom board contains all the rectifiers/capacitors, with the top board just being the actual motion controller.

15-05-2016, 07:26 PM
OK, hit my basic lack of knowledge at step 1 - select a BoB to get parallel to the 96-way connector. I thought all BoBs were about the same, but now bewildered by the choice! I don't mind investing in a decent one, just can't work out what I do and don't need

15-05-2016, 07:38 PM
Google pmdx126

You will also need a pmdx104

15-05-2016, 09:00 PM
Have you had a read through this thread? - http://www.mycncuk.com/threads/9829-Denford-Novamill-1996-Conversion-Hints-Tips-Appreciated?highlight=denford+novamill

It's for a Novamill, but the general cabinet wiring will be very similar.

15-05-2016, 09:08 PM
no ive not.

sorry he said it doesn't have an atc, scrap that you wont need any pmdx. any break out board will do

15-05-2016, 10:10 PM
Andy, that post wasn't aimed at you. It was more for some general info for John.
A PMDX BoB is still a possible optional, but in all honesty, that cheap 24V capable one that John S linked to in that other thread would probably do the job at a fraction of the cost.

16-05-2016, 08:57 AM
thanks Andy - lots of reading to do on the pmdx website
m_c - yes, I spotted that and am studying it to
fyi, here is the inside of the VMC 1300 Pro

16-05-2016, 07:10 PM
That's quite a bit different!

They're not using the onboard stepper drivers, so there's not really any point in keeping any of the existing motion controller boards. You just need to find a manual for the three stepper drivers that are fitted.
The biggest thing you'll need to work out is the wiring for the relay board in the centre.

Is the existing controller using USB? If so, does it still work, or do you not have the required software?

16-05-2016, 07:35 PM
m_c - the existing controller interfaces via USB to the Denford software and all works fine. It's great for students, but the machine is so capable that the project is to do the conversion, both to learn about control and to get to more "standard" software.
The steppers are MSD980 Microstepping Drive http://www.motioncontrolproducts.com/pdfs/msd980-microstepping-driver.pdf

The cabinet is nice and open so it's easy to see where each wire runs. A few other pics...

16-05-2016, 08:43 PM
Looks like that middle board also handles the stepper power supply, going by the transformer connections and capacitors. Have you found a wiring diagram for the machine, as it'll make working out exactly what that board does, and what signals it needs to work, far easier. If there's not already one over on the Denford forums, try asking as they're usually pretty helpful.

Is it running VR Milling 2 or 5?
If it was 5, I'd personally leave it until such time you have a reason to change. It may appear a bit 'simplistic' but it just works, and accepts standard G-code like most other controllers.

16-05-2016, 09:56 PM
There's a link in my post #4 to the denfordata forum with the schematic
I'm running VR Milling 5 and I'm not rushing to change - it's a project for me, so I can move at the pace I learn about the controllers and connections

17-05-2016, 07:24 PM
Helpful people at Denford confirm schematic Rev C on forum is for my model of VMC 1300 - I was impressed with them