Machsupport Forum

Mach Discussion => FAQs => Topic started by: tomcord on August 07, 2010, 04:58:03 AM

Title: plug and play with old machine?
Post by: tomcord on August 07, 2010, 04:58:03 AM
Hi
I have just purchased an 8 year old cnc router from a school. It all works but runs on some dos based system called pclathe which only imports autocad plot files. Its basically working as a plotter with depth control. So I want to get it up and running on mach 3. But I have no wiring diagram for the stepper motors or the driver board. It is all neatly connected to a power supply driver board and printer cable.  How will I be able to find out which pins do what? Are there standard configurations? Will Mach 3 just figure it out for itself when I just plug it in?

Any advice/help appreciated

tom
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 07, 2010, 05:57:11 AM
Hi Tom,

In answer to your questions it is just about a 'no' to all of them.  :'(

There is no easy solution without knowing more information, it may be possible but most solutions with old DOS machines is to replace the internal driver board.

Does the router operate from a 'parallel port' cable (as opposed to serial) ?.
Do you know the type and model of the router ?

Tweakie.
Title: Re: plug and play with old machine?
Post by: tomcord on August 07, 2010, 06:04:30 AM
hi
its this http://www.hme-tech.com/education/products/cnc_r50.htm  the R70 version I have contacted the manufacturers for more info but they have yet to reply
the software is very basic, its a parallel port
thanks
tom
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 07, 2010, 06:19:14 AM
Tom,

I have never seen one of these machines before and their website doesn't give much away either but if the machine is operated by 'step and direction' signals generated by the PC then there is a good chance that it can be used with Mach without too much hassle.

If,on the other hand, the stepper motor pulses are generated by the machines internal controller then there may be quite a lot of work to do.

A photo of the machines internal electronics might help.

Tweakie.
Title: Re: plug and play with old machine?
Post by: tomcord on August 07, 2010, 06:53:45 AM
hi
pictures of circuit boards with a heat sink removed attached
thanks
tom
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 07, 2010, 08:11:38 AM
OK Tom, excellent photos. This looks like it will be an easy one, well at least not very complicated.

A common convention (but there is no defined standard) is;
LPT Port Pin      2   X Step
                       3   X Direction
                       4   Y Step
                       5   Y Direction
                       6   Z Step
                       7   Z Direction

With pins 18-25 as GND or 0 Volts.

This is the very basic and initial connections required to move the motors but there may be an enable signal (e-stop) to be found also.
If it was me, I would connect the cable to your computers printer port and try configuring Mach with the above pin allocations (2 to 7) as trial and error and see what happens. Once you get axis movement then you need to set the steps per and velocity / acceleration etc. for each axis and get the directions right. (the Mach manual and videos will give you more details of this).

The next step is to find the limit / homing switch, e-stop and spindle control pins (2-9, 1[seldom used], 14, 16 & 17 are all output pins driving the machine functions) (10-13 &15 are all input pins connected to e-stop, limits, safety interlocks etc.) (18-25 are ground)

Good luck with the experiments.

Tweakie.
Title: Re: plug and play with old machine?
Post by: tomcord on August 07, 2010, 08:30:59 AM
thanks
will let you know how I get on

tom
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 07, 2010, 08:47:35 AM
Tom,

Just one point that is very important - do not disconnect any of the motors whilst the board is powered up.

Tweakie.
Title: Re: plug and play with old machine?
Post by: tomcord on August 07, 2010, 09:30:31 AM
on closer examination the pins being used are
1, 13, 25, 23, 22, 16
The rest of the pins dont appear to be connected to anything.
see picture

any ideas?

tom
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 07, 2010, 11:32:48 AM
Tom,

From that information I would think this is not designed to connect to the computers parallel port at all but to a, perhaps PCI, driver card fitted in the controlling PC.

Tweakie.
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 07, 2010, 12:37:29 PM
Hi Tom,

I have done a bit of searching on this but no luck. HME Technology are very cagey with their information but it appears to be a Rishton CNC designed machine. There is more than a good chance that your control board is for Serial operation using the (2) setup of pins 14,16, 17 and a computer installed driver.

If you are unable to get the necessary info from HME (bearing in mind that all suppliers to schools and the educational market are very guarded with their info and software) then the best bet would be to remove the board and fit another cheap 3 axis driver such as this one http://cgi.ebay.co.uk/3-AXIS-TB6560-CNC-DRIVER-BOARD-4-STEPPER-MOTOR-ROUTER-/110570269975?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item19be806d17
There are plenty of these type of boards available on ebay and, in my opinion, they represent an economic solution.

Hope this helps,

Tweakie.
Title: Re: plug and play with old machine?
Post by: tomcord on August 07, 2010, 01:51:11 PM
thanks for the help
I am planning on upgrading all the motors, board and software at some point. But I have managed this afternoon to get it running with the original software on a Win 98 pc via the parrallel port printer cable. It all seems to work but the stepper motors dont sound that healthy, and if I set the feed rates too high they give up, I wonder if they are getting a signal that is nearly ok but not quite right? Ive measured the travel with a DTE and its pretty spot on on all three axes, so something is right.
Anyway, it will do the job I brought it for for a while until I find a new driver  board and get a pc that will run mach 3

Tom
Title: Re: plug and play with old machine?
Post by: tomcord on August 08, 2010, 05:07:12 PM
Hmmm, tried it on a PC running mach 3 today with no output or signs of life at all.... Is it likely that I can just swap the driver board you recommend with the same power supply and other gubbins in the box of electrical tricks, or will I have to get a different power supply etc? electrics not really my forte
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 09, 2010, 02:05:44 AM
If what is says on the edge of your driver card "3 x 2A 36V" is correct then your existing PSU etc. should be just fine.

As mentioned earlier mach requires two outputs for each axis and your driver seems to only have 4 inputs for all 3 axis (not sure how this works, unless it only moves any one axis at a time).

Tweakie.
Title: Re: plug and play with old machine?
Post by: tomcord on August 09, 2010, 12:39:33 PM
x and y run together, but never seen x y and z running together.
tom
Title: Re: plug and play with old machine?
Post by: tomcord on August 09, 2010, 04:17:17 PM
why do you think there are only 4 inputs? There are six pins connected to the circuit board is that not 6 inputs?
Ive wired a different pin up to a 4.9v signal I found on the circuit board that goes off with the E stop, so the E stop now works, quite pleased with that! But I cant seem to persuade the stepper motors to do anything. With only one connected and just concentrating on one axis Ive tried all the combinations for the step and direction pin, with a few combinations one motor just about makes a noise when I use the jog keys, but I cant get it to do anything else, how do I know if its low active or high active?

tom
Title: Re: plug and play with old machine?
Post by: Tweakie.CNC on August 10, 2010, 02:33:34 AM
Hi Tom,

Quote
why do you think there are only 4 inputs? There are six pins connected to the circuit board is that not 6 inputs?

The standard PC parallel port consists of inputs and outputs (1-9, 14, 16 & 17 are all output pins 10-13 &15 are all input pins and 18-25 are ground).
So by my reckoning you have pins 1,14,16,17 to control the steppers and pin 11 as a feedback / interlock / etsop / whatever - pin 25 is ground.

The active high / low relates to the circuit design of the driver board and can be found by trial and error if it is not previously known.

Here is a link to a typical driver PCB with some setting up instructions which you might find useful. http://www.cooperman.talktalk.net/MDfly.zip

Tweakie.
Title: Re: plug and play with old machine?
Post by: hawkercnc on August 18, 2010, 04:58:46 PM
With regard to your machine it uses a HSE board which was also found on the Wabeco Machines a few years ago.  I bought one of these machines unfortunately as it had to run the software in DOS and needed an expensive dongle from Wabeco.  The board was designed to be 2.5D and not 3D.  I must say that I thought I had been well and truly ripped off.  The board had been purpose designed to keep people using their archaic software and dongle updates.  Anyway not to be defeated by this I contacted my great friend 'Sawston Steve' a great electronics and CNC guru and he examined the board and after some pondering, cut some of the tracks, added some components converted the board to full 3D and ever since I have using MACH3 on the machine.  This was about 5 years ago and I posted it - possibly on the CNC zone with all the photographs.  We should between us be able to resurrect this data if required.
Regards  John (Bedford UK)
Title: Re: plug and play with old machine?
Post by: hawkercnc on August 20, 2010, 06:36:17 AM
In considering the HSE driver boards, some older memories have been dragged up.  The HSE board to drive three axes had separate step pathways for each axis, but two of the three direction pathways went to a common terminal.  This made only 2.5 D machining possible. 

2.5D is as follows if you consider cutting a three sided pyramid, then the cuts for at least two of the base lines will involve changes in the x and y values all the way along the lines. This creates 2 oblique lines and this is known as interpolation.  If some height was added to create interpolation with x, y and z changing all the way along the line then full 3D is needed.  The early Wabeco would cut in one plane like a slice then there would be separate code for the next slice up and so on until the top of the pyramid was reached.  This gives a step sided pyramid rather than a smooth one. 

Sawston Steve looked up the application notes of the ICs (chips) involved (look up the IC numbers on the web to see the wiring diagrams) and as I said before altered the circuit board by cutting tracks.  However this progressed to a modification which involve removing an IC inserting a linking chip with a board above and hence modifying the board to be fully 3D.  This involved little or no soldering.  We thought of offering this to distressed Wabeco users stuck on DOS programmes with dongles who wished to use Mach 3, but did not manage to create any awareness of the potential product.  (The early Wabeco board was the HSE board)

The product was further refined by adding a box at the back of the control box which had full opto isolation, voltage control, speed control of spindle, spare relays and extra inputs and outputs for Mach 2 as it was at the time.

My Wabeco machine still with it’s HSE boards has full 3D, a fourth axis, a view cam camera attached, Accurite struts which read through the Accurite box and display and then into Mach 3, meaning at least that I have a measuring microscope, spindle speed read out and control via Mach 3 and still have spare inputs and outputs.  There are of course 2 parallel ports to handle all this.  All this was care of Sawston Steve.  He reckons that he has at least one board left.  If interested get in touch.

As an aside no one seems to ever mention the fact that if you have a couple of DRO (digital read out) struts from a big machine in a scrap yard ( Steve cut my down to the right length) or a rotary encoder without the read out boxes you can use Mach 3 to read them.  Therefore an old computer with Mach 3, a couple of old DRO struts,  a view cam and some sort of sliding x. y table and you have a digital measuring machine.  Again a rotary encoder attached to the headstock of your lathe, an old computer, mach 3 and essentially you have the basis of a highly accurate rotary measurement device, to cut facets, drill PCD (pitch circle diameters) or cut gears.

Title: Re: plug and play with old machine?
Post by: Fastest1 on October 20, 2010, 03:34:55 PM
I can understand replacing the board so you can communicate but leave the steppers unless you physically need more power. Most steppers can outpower the end mill they are trying to cut with (2 piece end mill anyone? junked parts?) Also needing a stepper to go faster isnt needed til you are lighning fast on the Estop! Maybe on a big router but on a little machine and not much experience with cnc (an assumption) they move fast enough where you wont react til the crash has happened and the belt is smoking! Dont ask me how I know that!
thanks for the help
I am planning on upgrading all the motors, board and software at some point. But I have managed this afternoon to get it running with the original software on a Win 98 pc via the parrallel port printer cable. It all seems to work but the stepper motors dont sound that healthy, and if I set the feed rates too high they give up, I wonder if they are getting a signal that is nearly ok but not quite right? Ive measured the travel with a DTE and its pretty spot on on all three axes, so something is right.
Anyway, it will do the job I brought it for for a while until I find a new driver  board and get a pc that will run mach 3

Tom