Messages

7291

Tangent Corner / Re: New Here!

« on: June 23, 2009, 02:11:07 AM »

Hi Dom,

An chance you could post a couple of pictures ?.

Tweakie.

7292

General Mach Discussion / Re: How do i setup Mach3 to control a laser with TTL input?

« on: June 13, 2009, 10:13:06 AM »

Hi Borge,
The laser TTL spec is usually <0.5volts for off and >2.0 for on. Providing it does not draw any appreciable current this input can be connected to the Z axis direction pin  on the BOB so that it turns the laser on for -Z moves and off for +Z moves. I disable the Z axis so that the laser focus is not disturbed and use the Z axis DRO scale factor to control the 'laser bite time' (which varies from material to material). If the laser operation is reversed then change the direction active low under ports and pins.
Although I have used this method quite successfully I now favour a simple shutter system to switch the laser beam on and off, again using the Z axis direction signal as I believe that longer laser life will be achieved by using a soft start when it is turned on from cold.

Tweakie.

There is some further information here :-

http://www.cooperman.talktalk.net/index_files/Page4549.htm

7293

General Mach Discussion / Re: murphy and his law

« on: June 13, 2009, 09:52:36 AM »

When things go bad they really do go bad. Murphy's brother said that.

Tweakie.

7294

General Mach Discussion / Re: couple of things I have noticed with mach /g83 problem

« on: June 13, 2009, 09:39:44 AM »

I think that the way to go is to look for a GCode editor that can modify the Mach Wizards code (or any other) to obtain compatibility with your controllers. Some of the editors I have seen in the past have quite sophisticated 'search and replace' capacity and may do the job.

Tweakie.

7295

Tangent Corner / CNC versus TV.

« on: June 11, 2009, 02:48:40 AM »

Since developing an interest in CNC I don't get much time for watching TV - unlike all my neighbors.

Tweakie.

7296

Tangent Corner / Re: David Laser Scanner

« on: June 11, 2009, 02:46:12 AM »

Results look pretty good to me Chris - I can see you making rings that include the finger as well. 

Tweakie.

7297

Show"N"Tell ( What you have made with your CNC machine.) / Re: Engraved in Stainless

« on: June 10, 2009, 08:23:17 AM »

Thanks Ed.

Tweakie.

7298

Show"N"Tell ( What you have made with your CNC machine.) / Re: Engraved in Stainless

« on: June 09, 2009, 06:25:50 AM »

Nice job Ed.
What cutter or bit did you use ?

Tweakie.

7299

General Mach Discussion / Re: which limitswitch is being triggered

« on: June 09, 2009, 06:17:50 AM »

if your limit switches are each wired separately to an input pin then yes Mach screen Diagnostics will tell you but if your limit switches are all serial or parallel connected to one input pin then the answer is no.

Tweakie.

7300

General Mach Discussion / Re: better to ask first than pay later

« on: June 07, 2009, 12:25:39 PM »

Before you go buying anything and for what it is worth, I would suggest that steppers will be far too slow for a table that size and you will be disappointed with the time it takes for the rapid positioning moves and that servo motors are the way to go.

Tweakie.