Messages

5071

G-Code, CAD, and CAM discussions / Re: Mach3 adding extra loops in a string of arcs

« on: February 16, 2013, 03:58:41 AM »

Hi Guys,

I am sorry to be an absolute pain but obviously I am missing something here. 

I ran the posted ‘fender jaguar.txt’ file last week and could not see any problems – could you please enlighten me on just what the problem is ?

Tweakie.   

5072

Tangent Corner / A Microscopic view.

« on: February 16, 2013, 03:06:36 AM »

An interesting video showing what happens when we machine metals (and presumably other materials)   http://www.youtube.com/watch?v=mRuSYQ5Npek&feature=player_embedded#!

Tweakie.

5073

Show"N"Tell ( What you have made with your CNC machine.) / Re: Isolation Routing PCB's and Local System Rotate.

« on: February 16, 2013, 02:24:33 AM »

Hi Richard,

Thank you for the information, it is most useful to know what causes and cures problems as this will inevitably be of help to others that follow.

That damn Watchdog - I suppose it is of use to somebody 

Tweakie.

5074

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: February 15, 2013, 04:08:59 AM »

I have been following recent work (done on another forum) with low power lasers producing images using printer Toner.

I had to give it a try using my 40W CO2 laser and this was my first successful test run on a scrap piece of Oak.

IMPORTANT - It should be noted that it is unwise to experiment with fine powders in a confined space so for any that follow please observe the necessary safety precautions and always have a suitable fire extinguisher standing by.

Tweakie.

5075

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: February 15, 2013, 04:04:40 AM »

Hi Yanxin,

I am looking forward to seeing some pictures of your work.

(You are quite correct about the Impact / Laser plugin - it uses a fixed time interval (PWM) of 40uS and a variable repetition frequency (PRF) of between 0 and 12.5 kHz and, of course, fires the laser whilst the axis is moving).

Tweakie.

5076

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: February 14, 2013, 12:44:11 PM »

Hi Yanxin,

DotG has been designed for reproducing a one bit, ‘dot-dithered’ image (one with a varying density of equal sized dots to create the illusion of shade) and when set in ‘dot’ mode the laser is only fired when the X and Y axes are stationary.

To fire the laser I am using the M11P1/M10P1 command set together with an imaginary B axis and my Post Processor (see posting #641) essentially creates this code for each dot in the image:-

B0

M11P1 B1
M10P1 B0

B0 is at the start of the code and makes sure the imaginary B axis is in position 0.

M11P1 turns on Output #1 (as soon as the B axis starts to move). Output #1 is mapped to an LPT (parallel port) output pin which is in turn connected to my laser TTL(L) trigger.
Because the imaginary B axis takes time to move from position 0 to position 1, I have adjusted (by trial and error) the steps per unit, Velocity and Acceleration of this axis to produce the required time delay (laser on time).

M10P1 turns off Output #1 and thus the laser trigger as soon as the B axis starts to move back to position 0.

I hope this answers your questions.

Tweakie.

5077

*****VIDEOS***** / Re: Laser Cut Frame CNC Router New build

« on: February 14, 2013, 05:51:43 AM »

Hi John,

I have never been an advocate of belt traverse but I obviously need to do a re-think as you certainly have shown that a high degree of positional accuracy can be obtained with your (hive mind) design.

What sort of things are you planning on making with the new machine ?

Tweakie.

5078

Show"N"Tell ( Your Machines) / Re: 4 axis bedmill retrofit

« on: February 14, 2013, 05:39:50 AM »

Hello Machine Head

Autolisp?

I have an Acad license. If it is not your personal IP I would be very interested in trying it.

Cheers
John McNamara 

Autolisp details are here http://www.jefferypsanders.com/autolisp.html

Tweakie.

5079

General Mach Discussion / Re: New PlugIn just about done..

« on: February 14, 2013, 05:22:11 AM »

If it's of any interest...

Something very similar regarding axis creep after jogging came up here http://www.machsupport.com/forum/index.php/topic,23460.0.html

As far as I know, it was not resolved.

Tweakie.

5080

*****VIDEOS***** / Re: Laser Cut Frame CNC Router New build

« on: February 14, 2013, 04:53:06 AM »

Absolutely excellent work John - a machine and construction technique to be proud of. 

Thanks for sharing.

Tweakie.