Messages

861

General Mach Discussion / Re: monitor too small

« on: March 02, 2008, 08:22:22 AM »

At my age I ask my GRANDSON !!!

862

General Mach Discussion / Re: Spectralight or Inteltek lathe question

« on: March 02, 2008, 08:13:20 AM »

No - Ports and Pins have nothing to do with what machine you are using. The Sherline mode was to do with Sherline, but you seem to be saying that you have ripped out all the old electronics and substituted some board you bought on E-Bay.

I will assume the machine has stepper motors. You should wire it up, therefore, according to the instructions that come with your Easy CNC Driver board.

Since to board comes with a 25 pin socket to take the lead from your computer, the connections to the socket will be pre-wired. The LPT1 socket from your computer has four sets of pins. 1) Pins 2 - 9 outputs to the driver - usually used to drive the axis (one step and one direction each) maximum 4 axis. 2) Pins 1,14,16 17 - another four output pins - usually used for spindle motor control and coolant. 3) Pins 10 - 13, 15 - Five input pins - usually from home switches and limit switches or spindle rpm counter. 4) Pins 18 - 25 - These are signal ground (0v) connections to the computer and have no other use.

You will have to read the documentation and find out  how pins are allocated - particularly pins 2 - 9. You can then set up Configuration/Posts and Pins accordingly.

If you have a lathe - is this a two driver board, or a three driver board. If it only has two driver cards in it, then you will have spare output pins available (probably 6 - 9) to drive other things, (3 driver - 2 spare pins) if you can get to them.

You are leaping on a bit - how does the tool turret drive - if this is a stepper motor as well, then the answer is yes - you can drive it using the spare output (if you have bought the three driver card). You may have to write your own software - or someone on the forum will help. A simple way would be to designate it as the A axis, and set the number of steps per unit to a figure that moves the turret by one position. You could simply use G Code to move the tool - G0 A1, G0 A2 etc - but I would leave that til you get the two main axis up and working

863

VB and the development of wizards / Re: Using a custom DLL

« on: March 01, 2008, 10:59:17 AM »

If you are asking "is there a code to make Vis Basic wait whilst the present move is completed" then that is

While Ismoving
Wend

The Script Tutorials are now back - albeit in a new format.

864

General Mach Discussion / Re: unwanted Momentary outputs using oem trigger start

« on: March 01, 2008, 10:37:38 AM »

I take it you are using a mechanical switch, in line with the start button on the Mach 3 screen.

The lines into the computer are held to 5v by weak internal pull up resistors. You say that your switch is active low - so it is closing to 0volts. The problem probably is that the internal pull up resistor is not strong enough to overcome all possible pulls to zero - including the length of you cable.

You would be better to change the Push Button from single contact to a change over switch, and have both sides wired - one side through a 100K resistor to 5volts, the other to ground. This will ensure a good 5 volts signal on your input when it is OFF.

865

General Mach Discussion / Re: Can someone review my code adn explain M01

« on: March 01, 2008, 10:25:52 AM »

Your program, before the M01 quite rightly cancels all offsets.

If you then look at the two lines after the tool change to Tool 1 and remarks, you will see a G54 call and a G43 call.

These call for offsets from different tables - and when the table then moves, it will apply them.
The G54 offset comes from the table in Config/Fixtures and the G43 comes from Config/Tool Table.

Open both these tables and make sure there are no offsets for G54 and for Tool 1.

Alternatively you can cancel the G54 and the G43 call, which will leave your tool where you set it.

866

General Mach Discussion / Re: Duplomatic lathe tool turret with Mach?

« on: March 01, 2008, 09:19:34 AM »

It seems a bit expensive to go to programmable logic, when you have a computer sat there, which, while the PLC is working, will be sat doing nothing. The problem with programable logic chips is you are programming in machine code and, unless you have the development tools, you will have to buy those as well.

You can get a download from Microchip, which emulates their chips and allows you to write programs, but then yo need the hardware to program the chip.

I would have though it would be just as easy to get another port for the PC and use that. Programming can be using Visual Basic.

Looking at the diagram you downloaded - do you need a wire to each station - or can you put a binary signal to a group of wires - which selects the staion you want.

That doesn't matter a great deal, however. The thing to do is identify all the outputs you require and build the interfaces, particularly those to control the three phase motor, and the relays or whatever for the various locks.

The logic to control it would, I think, be fairly simple at the side of that.

867

General Mach Discussion / Re: inconstant speeds?

« on: February 29, 2008, 03:58:20 PM »

Being the old **** that I am, I did a Vis Basic program to calculate the various positions in relation to a straight line, given the figures that you have quoted.

None of the figures is more than 1 percent, and most are under 1/2 percent of a stright line - so you are working to fine tolerances. I hadn't noticed your comment before I started - and so I did it.

I am a steel man, myself, and these minute changes of curve would be all but un-noticed - do they honestly make all that much difference - I know the competition is quite fierce out there.

868

General Mach Discussion / Re: inconstant speeds?

« on: February 29, 2008, 02:30:48 PM »

As you can see they are tiny movements. You do not say, but I hope this is in inches.

I would plot them out on a graph and see if I could replace two or three with a curve. You have the start and finish points so the only thing to study is the radius of the replacement curve - and you can fill this in GCode using R instead of IJK. I would have though a suitable curve woud give a better line anyway - unless you are designing a stealth bomber.

869

General Mach Discussion / Re: Question around operation and parameters

« on: February 29, 2008, 02:20:23 PM »

As far as I understand it, reading the Mach specific functions and things in Vis Basic the tool numbers are obtained by functions.

Function GetCurrentTool() as Integer
Function GetSelectedTool() as Byte

The first function returns the currentl tool, the other returns the number of a selected tool (but not yet implemented)

My problem is I am now screwing round in my mind to remember how to use functions in basic !!!

870

General Mach Discussion / Re: Hall effect home switches - Nonsense and bother

« on: February 29, 2008, 03:52:27 AM »

I am just trying a laser screwed onto the cross slide, shining at a detector at the end of the lathe - I will let you know how accurate this is. I am not too hopeful, the laser seems a bit "wide-beam" but if I mount it, and the detector behind a lemgth of narrow tube, I should be able to get reasonable accuracy - the parts were £10 for the laser and £1.25 for the detector(s) - so not too expensive.

At least this way, there is nothing for the machine to crash into.