Messages

1

General Mach Discussion / Re: I need a bit of help

« on: March 07, 2010, 01:17:52 PM »

Not sure how helpfull this will be,
For some (most?) Fanuc machines it is not wise to move in Z with CRC active, i would turn CRC on and off inside the Sub, moving to and from depth before and after calling the Sub. Also another couple of CRC "Rules" were must turn on and off with a move (between 90 and 180 degrees to profile) and the move should be larger than the rad of the cutter.
These were unbreakable rules on older machine controls, so rules i have always used - only just started using mach so not 100% sure in this case.
Good use of incremental, alternative would be a datum shift, have to watch out for carried errors with inc.

2

G-Code, CAD, and CAM discussions / Re: Are there cutting depth, spindle speed and feedrate tables available?

« on: February 16, 2010, 05:31:02 AM »

See attached.
A handout i use with classes just starting with CNC programming / Milling.
It has a couple of questions on it - work them out, i can check my answers then?
It is metric - most students struggle to understand the 1000 in the RPM formula, it is only to use M/min surface speed with tooling measured in mm.

3

G-Code, CAD, and CAM discussions / Re: Which code to remove in order to remove "homing" in multiple work offsets.....

« on: February 03, 2010, 08:24:23 AM »

N198 G91 G28 Z0.
N199 G28 X0. Y0. A0.
(--- G55 Work Offset Was Added ---)
G55
%
O0000


It is the G91/G28 lines returning the tool home - G28 machine coordinates X,Y,Z zero's being machine home, you should make the tool safe before changing work offset, you could move absolute above the jobs rather than return to home.

4

G-Code, CAD, and CAM discussions / Re: Warning-zero length line?

« on: January 22, 2010, 09:35:30 AM »

sometimes get something like this when importing and exporting data, tolerance settings (say for iges) on import and export can be used to merge data points or remove short lines (0.000001mm level of size), you may have some thing like this happening when you are scaling - a line or edge was larger than this but scaled the system may try to remove but can't (can't merge points), have come across with 3d CAD systems (not often) - try scale factor very slightly different size (0.501 rather than 0.5) or try to scale in native CAD system.

5

General Mach Discussion / Re: Supplier of small quantities of Titanium and machining recommendations

« on: January 13, 2010, 10:01:47 AM »

think i might go and have a long sit down to consider all of the above now

Julian

6

General Mach Discussion / Re: Supplier of small quantities of Titanium and machining recommendations

« on: January 10, 2010, 06:01:03 PM »

http://www.goodfellow.com/home.aspx

http://www.goodfellow.com/E/Titanium.html

7

G-Code, CAD, and CAM discussions / Re: G52

« on: January 06, 2010, 12:45:17 PM »

To move back to the original start of first component, i would;
G52 X0 Y0
G0 X0 Y0    ie cancel local coordinates and then move to zero/zero.

I think you want to set up new coordinates for each work piece datum, and then use them (as above - set up with G52 and then move to start position).

It is a while since i have programmed like this (10 years) - CAD CAM makes it easy to be lazy.

8

G-Code, CAD, and CAM discussions / Re: G52

« on: January 06, 2010, 12:02:52 PM »

G52 sets up local coordinate system, should you then move to the start position in x/y then down to depth?

G52X-22Y0
G0X0Y0 (or wherever the start coordinate is)
G1Z-1F90

Julian

9

Mach4 General Discussion / Re: New people welcome !! Come in here and introduce your self!

« on: January 06, 2010, 09:49:34 AM »

I will shortly have a 3 axis router running from mach3 - just purchased from Exel CNC.

I have many years experience with CNC, use Solidworks and EdgeCAM. Will look at producing patterns and models again! Ran a product development business before, now teaching at the local college - and yes do teach CAE / CNC / CAD / CAM - i don't need to be tested too hard, don't want to be found out!

Looks like a well supported forum - looking forward to joining in - well asking for help?

Any one got a reliable post processor for Mach 3 / EdgeCAM?

Julian