Messages

1781

G-Code, CAD, and CAM discussions / Re: crank shaft

« on: December 30, 2007, 09:24:41 AM »

Are you trying to make it on a lathe or a mill?

Graham.

1782

General Mach Discussion / Re: OK that does it!

« on: December 30, 2007, 09:02:27 AM »

Well at least its better than before. 

when cutting threads you should always use exact stop mode if cutting into a groove. if you use cv then the thread can become tapered towards the end of the cut due to cv blending corners.

The slight pitch error is probably the reaction time of your machine and the signal processing time of your system.

To get the best results from threading you must allow time for the machine to react, even on fast industrial machines you have to allow acceleration and deceleration times.

Allow 5mm (.200")  in front of the thread for acceleration and 2.5 (.100") if possible at the back for deceleration. Also keep the speed down, if the exit looks ragged halve your speed.  It is impossible to say what speed to use as every machine is different but start low e.g. 100 rpm and work up.

Using the new macro you could issue a L720 and allow the thread to feed out over 2 pitches thus giving a very smooth and neat exit.

Graham.

1783

G-Code, CAD, and CAM discussions / Re: skull and crossbones G code

« on: December 28, 2007, 06:29:17 AM »

Sorry Guys,

I did not think the post needed a reply, it looked more like a statement than a question. Sorry,

Graham.

1784

General Mach Discussion / Re: OK that does it!

« on: December 26, 2007, 05:55:32 PM »

I have sent the macro to Brian and Art, as I do not have the authority to post modified versions of there original code they will decide if it gets into the distribution.

Sorry, its all I can do at the moment.

Graham.

1785

General Mach Discussion / Re: OK that does it!

« on: December 26, 2007, 05:23:27 PM »

I think the macro was a bit wrong.

I have recoded it to work like the big machines do it.

So the tool now comes out over a rotation angle set by the L word.

L180 will bring the tool out over .5 of a pitch L270 over .75 of the pitch etc.

Graham.

1786

General Mach Discussion / Re: OK that does it!

« on: December 26, 2007, 04:33:38 PM »

I have sent a new G76 macro to Brian and Art for there approval, if my code is right this should hopefully fix the problem.

Graham.

1787

General Mach Discussion / Re: OK that does it!

« on: December 26, 2007, 11:15:03 AM »

That's a new one to me, I have asked Art for comments.

Graham.

1788

VB and the development of wizards / Re: Macro VB Script for Lathe Toolchanger

« on: December 26, 2007, 07:03:05 AM »

Helmut,

if your machine has homing switches fitted then one way to go to a safe position is by using G53 Xnnn Znnn this is a known point in machine coordinates from the zero return point.

Graham.

1789

G-Code, CAD, and CAM discussions / Re: DFX to G Code

« on: December 26, 2007, 06:20:19 AM »

 

Graham.

1790

General Mach Discussion / Re: OK that does it!

« on: December 26, 2007, 06:19:23 AM »

 

Graham.