Hello Guest it is March 29, 2024, 11:12:07 AM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - jimpinder

1061
Paul = sorry to but in on your post, but I have also asked for some help with tool offsets I have tried various combinations without much success. I can get the offset, but not the one I was expecting. I noticed your file "bogie equaliser" and wondered if you were machining miniature railway parts. Thats what I am doing at the moment.

The reason I butted in - I also use Turbo Cad - I have had it a long time - several years now, but my version does not write G Code. Can you get an add-on for this. I quite like Turbo Cad and would like to keep using it if possible.

Heres hoping Graham comes back with the reply to our G40 query.

1062
How does the computer know when the spindle is up to speed or has stopped - is it waiting for these events before it progresses.

I would leave out the speed instruction and see if it responds any differently

1063
G-Code, CAD, and CAM discussions / Re: General newbie cnc question
« on: October 17, 2007, 12:11:20 PM »
I may be way off line here, because I don't have a good cad/cam program, but what I would do when I had finished modelling the whole part is to then divide it in two with a wall across where your 5 inch limit is. My turbo Cad program could do this so others should.

The wall can be the smallest thickness measurement your program can take, but should extend out from the main piece by a reasonable amount all round.

When your program then converts this to GCode it should do one side of the wall before climbing over and doing the other side.

If you insert an M1 in the code to stop the program, you can then move the part by a set amount.
As Brett says if you have some locating lugs on the part, you can then move it quite precisely.
Reset the DRO's on Mach 3 to the new location (i.e. 5 inches up from where you were) and let the program carry on.

The wall, if very thin, will either clean out easily, or break off in the general machining, particulary if you allow for the thickness whn moving the part.
I don't know whether this will work but I've read it over again and it sounds reasonable.

1064
G-Code, CAD, and CAM discussions / Re: loop question with mach3
« on: October 17, 2007, 11:54:18 AM »
I have found that the easiest way  to do repetative things is to write a visual basic script. I have written several of these. I use DRO's to put in the information, such as start values, finish values, cut increments and lengths. The script takes the values I have put in the DRO's, e.g. start value 1 inch, finish value 1/2 inch, increment 20thou, length 3 inches. and then out puts the G Code to the lathe, each time taking the 20 thou cut until it arrives at the finish value.

It works very well and only take one command to implement it.

I have five of these Macro scipts for various little roughing out jobs which I can insert in any program at will. There is a guide to visual basic scripting in the video tutorials.

1065
G-Code, CAD, and CAM discussions / Re: Newbie Question Gcode
« on: October 17, 2007, 11:42:30 AM »
Yes G00 and G0 are the same - on some programs you see G00 and on others you see G0, and with Mach3 case does not matter either.

Graham told you about modal commands - those that stay in effect until another comes along either to change or cancel it. HOWEVER you will find, if you are just starting out with G Code, if you are writing your own stuff, it is better to put the command in again (it doesn't matter) so that each line is self contained, or at least each "paragraph" is. When you are debugging, it is a lot easier to have the code there in front of you, than have to run back through the program to see the last modal command.

As far as speed override is concerned, you will find, if you are set up in inches, then change to metric, Mach3 changes to metric, but it also changes speeds to metric e.g. my max speed is 4 inches p.m. but this changes to 4 mm p.m. if I change. I can overrirde this and change it up to 100 (the equivelant of four inches)- without touching the motor tuning page again and alter all the settings on there.

Don't ask me why I can only get four inches a minute out of my steppers, it must be a combination of the motor, the gearing and the lathe (a Warco metalworking lathe). I can get the motor to turn faster but then they start to judder etc and miss steps. I will have another go at them soon, but at the moment I'm limited to 4 inches!!

1066
G-Code, CAD, and CAM discussions / Re: G code help
« on: October 17, 2007, 08:34:06 AM »
Yes - I am used to programming a computer with sub-routines so I got caught as well.

There are two ways - Gcode has a subroutine call M98 and the subroutine returns to the main program with an M99 code.
You can set up a group of offsets to move the table, and then call the sub-routine to drill.

If it is just a drilling an array, then you might prefer to write a macro in visual basic, where you might like to write "for x = 1 to 6, for y = 1 to 8, drill x,y" . Thats not the whole program of course but it could be just a few lines like that. Store the macro, put your workpiece in place and just call the macro.

I have several Visual Basic macros I have written for rounding the ends of bars, thining down axles and rods etc that take information from a set of DRO's I have inserted on a page, then I can call the macro's from within any program, just for that one job - then carry on the rest of the program.

If you are drilling an array of holes, then I think the macro would be the simpler bet - is it for drilling electronics boards or something similar ?

1067
I am milling - in metric
I am starting at X0 Y0

I want to move out to X20 (which is the side of the workpiece) then mill up to Y20
The simple code is G0 X20, G1 Y20 - but in reality I want the table to move to position X24 and I only want to mill up to Y16 to take account of the tool diameter (8mm) (I then want to move back to Y0, move in 0.5mm to X19.5 and take another cut, and so on, down to 10mm)

I have tried several combinations of G40, 41 and 42, but I do not seem to have struck the right one. I can get the tool to compensate for diameter, but never in the direction, or on the axis that I think - HELP



1068
General Mach Discussion / Can I have a beep and a flashing icon ???
« on: October 13, 2007, 02:06:36 PM »
Once my GCode is running, I don't like to just stand and watch it in awe, so to speak, the big advantage is I can get on with something else.

If I put in a suitable Macro at stages in the program that require my attention, e.g. a tool change, I would like the computer to signal me when it gets there.

Does Visual Basic have a "beep" facility, and can I flash an LED on the screen. Is this a problem for the "brains"

 

1069
General Mach Discussion / Re: motors turn one way only
« on: October 11, 2007, 02:48:59 PM »
I thought we were covering this on your other post - have we moved the problem here, now.

As Hood said - are you getting a signal change on your direction pin?

Will the motor reverse ?????  Is your driver card faulty ??

1070
General Mach Discussion / Re: Output Problems
« on: October 11, 2007, 02:40:59 PM »
I have just built a four relay driver board, using a darlington array to drive four 5 volt relays for motor and coolant control.
I am using pins 8 and 9 for M3 and M4 and pins 16 and 17 for M7 and M8. (I think I might have damaged pins 1 and 14 earlier)

Pins 8 and 9 seem to work fine and M3 and M4 are reliable. When  I was testing M7 and M8 commands, I sometimes got intermitent results. It seemed that I could get M7 on, but sometimes M8 would only go on if M7 was on. M9 turned both off. I don't know how Mach3 interprets this Macro.

I would try using say pins 8 and 9 and see if you get the same results, or put the Z drive on a different pair.

I must admit I cannot see how this would be affected though.