Messages

6511

General Mach Discussion / Re: Non-integrated Video Card with 32MB RAM

« on: August 11, 2010, 11:27:42 AM »

Think that's normal for the driver test, mine does that as well.

Tweakie.

6512

General Mach Discussion / Re: Non-integrated Video Card with 32MB RAM

« on: August 11, 2010, 07:19:47 AM »

Just a thought, from my personal experience.....

I run long programs (340,000 +) and never have any problems (probably will now I have boasted about it) and I swear by Windows XP SP2.
I don't run anything else on the dedicated machine PC but Mach. I once upgraded it to XP SP3 and then everything went pear shaped, I reformatted the drive, re-installed XP SP2 and everything smells of roses again. I don't know the exact spec of my PC but it is old and nothing special (does have good driver test results though).

Tweakie.

6513

General Mach Discussion / Re: How to calibrate unit - i.e. ensure that x0 and y0 are always the same

« on: August 10, 2010, 01:13:06 PM »

I don't use sensors on my CNC but I think that the fully enclosed, short distance type would be better ( similar to this http://cgi.ebay.co.uk/CONTRINEX-DW-AD-703-M8-3MM-INDUCTIVE-PROX-SENSOR-NEW-/260465431469?cmd=ViewItem&pt=UK_BOI_Industrial_Automation_Control_ET&hash=item3ca4f313ad )
There are many manufacturers of this type and you should be able to find a couple at a good price.

If it were me I would investigate your problem with skipped steps and resolve that issue as a priority. My machine (although small in comparison) regularly runs GCode programs in excess of 340,000 lines for 8 hours at a time with no lost steps or loss of position and I think this is true for all regular Mach users. The machine size is not really relevant as long as the axis are free without binding or tight spots etc.

Tweakie.

6514

General Mach Discussion / Re: How to calibrate unit - i.e. ensure that x0 and y0 are always the same

« on: August 10, 2010, 11:54:57 AM »

I was thinking of purposely sending the unit past 0,0 something like -1, -1 (the machine will skip a little) and then reset the x,y DRO to 0,0.

I don't think this is to be recommended unless the current to your steppers is small enough to ensure that no damage could be caused by hitting the buffers (so to speak).
Surely a better way would be to fit home switches / sensors and use the built in Mach routines for homing.

I suppose I have to ask the question - Why are your axis losing position in the first place ?.

Tweakie.

6515

FAQs / Re: plug and play with old machine?

« on: August 10, 2010, 02:33:34 AM »

Hi Tom,

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.

6516

FAQs / Re: plug and play with old machine?

« 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.

6517

Show"N"Tell ( Your Machines) / Re: Dixie Duke - A machine in the making.

« on: August 09, 2010, 01:58:15 AM »

Great work Sam - at this rate it will be making chips in two weeks   

Tweakie.

6518

FAQs / Re: plug and play with old machine?

« 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.

6519

FAQs / Re: plug and play with old machine?

« 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.

6520

FAQs / Re: plug and play with old machine?

« 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.