Messages

21

General Mach Discussion / Re: setting the exact home for 2 different files

« on: July 21, 2020, 02:25:46 PM »

I'm also very new to Mach3 and CNC but I think that adding  M6  where you need to change the tool will wait for you to do so and then click on [ Start ] again once you've done so.


Someone with more knowledge will no doubt confirm or deny my assertion 

22

General Mach Discussion / Re: G82 Drilling Cycle

« on: July 21, 2020, 08:52:14 AM »

No  -  that is what I've been doing and it 'Orbits' quite correctly (as I would expect)  but doesn't change the 'Centre of Rotation' which is what 'Panning' ought to do.

I've also tried zooming out and then clicking to the right or left of the image to zoom in about that point - without success.

23

General Mach Discussion / Re: G82 Drilling Cycle

« on: July 21, 2020, 06:52:21 AM »

I've been held up in this endeavour due to slow delivery of components but they arrived yesterday so I'm back on it.

When trying a simulation (cutting air) on my workshop system I had a 'Soft limits error' --- which I think I've solved  ---  but when investigating I came up against another 'irritation' in Mach3 regarding the [ Table Display ]  window.  I can 'Zoom' and move the display 'in orbit' OK (even turning the whole thing upside down) but I can't yet see a way to re-position the viewpoint - which effectively means 'panning'. I'm familiar with similar displays in SketchUp etc. where panning is a matter of 'shift' if you are in 'Orbit' but none of the modification keys ( Ctrl etc.) seem to have any effect. Nor does [ Display Mode ] appear to do anything, which might have been an option.


It must surely be my lack of experience with Mach3 controls but I've yet to find anything intuitive that works to modify the display - nor anything in the 'help' to point me to a solution 

Can someone enlighten me ?

24

General Mach Discussion / Re: Simple radius cutting - isn't !

« on: July 21, 2020, 03:13:43 AM »

That's a very useful analogy Tweakie -- I agree that Power Steering is utterly indispensable   

If you look at my profile you'll see that I also 'Looked at' Mach2 in 2007 but I didn't have a machine at that time and I'd even forgotten about it until I tried to register on the forum last week so naturally was not aware of the history.

Essentially the 'arithmetic'   -  not even 'Maths'  -  involved in calculating the tool-paths for shapes that can be easily determined by hand-coding is quite trivial. It would be a different matter if I was trying to plot NURBS curves by hand!

I might get as far as plotting a Reuleaux Pentagon (as in my Avatar) but that could be a bit challenging.

My real concern was that the errors I am finding might be down to a fault in my S/H Denford MicroRouter and the reason for it being sold on.  I've already found that the vertical alignment of the motor was compromised (now corrected) but it's good to know that my fears are mis-placed.

25

General Mach Discussion / Re: Cutting under or over size depending on software

« on: July 20, 2020, 01:42:23 PM »

Have you compared the G-Code generated by the two programs against each other?

Is there a difference in the dimensions in the G-Code?

26

General Mach Discussion / Re: Simple radius cutting - isn't !

« on: July 20, 2020, 10:26:41 AM »

Thanks for that re-assurance Tweakie  -  even though the concept may be old, it shouldn't make it obsolete surely ?

To me it seems a very obvious way to simply draw the component 'at size', code accordingly and simply use G41 or G42 with a suitable Cutter offset to cut either a 'Pocket' or a component to fit that pocket.

It seems that currently (hand coding) I have to deal with the offset manually - it's no great shakes really but copying a few blocks of code and then going through it to apply the offset is prone to potential error -- I am only human and therefore inherently error prone 

27

General Mach Discussion / Re: Simple radius cutting - isn't !

« on: July 20, 2020, 09:14:13 AM »

I'm not quite tearing my hair out but I am getting very confused at what Mach3 is telling me and how it 're-interprets' the same G-Code after very minor changes !

One error message this morning was "Tool radius greater than approach Line #19"  ??   Line 19 is G01 Z-34 ??

Removing that line - which was redundant due to the previous Z setting being Modal - cleared the error.

It also told me that the previously good reference to I-40  was wrong and would only accept I40  ??

Trying the use of G61 to turn CV on or off has caused all manner of weird effects such as the 20mm rad becoming a chamfer ??  -   the 10mm rad a ¼ ellipse, an 18mm rad or a 14mm chamfer -  and the 90º corner anything between 5mm rad and 70mm rad ?

I've resorted to closing and reopening Mach3 and even switching the Denford off and back on again  - all without regaining any 'consistency' !!

I'm beginning to think that 'Tool compensation' is not the way to handle 'Pocket' or 'External' cutting 

28

General Mach Discussion / Re: Simple radius cutting - isn't !

« on: July 19, 2020, 08:59:02 PM »

I understand most of that code Graham but to get a fuller understanding I've imported it into Mach3.

The simulation starts, but stops at line #8 giving an error "Tool radius not less than arc radius with comp..."  ---  I imagine that could be due to my copy of Mach3 having no entry for Tool 2 and although I have tried entries for the diameter of 5 and 10 it still  won't progress. 


There may need to be other entries needed but I haven't yet investigated the tool table so I'm 'flying blind' as it were


I do have CamBam installed but I'm initially looking at the very simple primitives of G-Code that can be done by hand to get a good grounding.  Ultimately I would like to get my head around the finer points, that's why I'm looking for pointers toward a fuller list of codes detailing what parameters are needed for each.


I have fathomed the fact that (normally)  I & J are incremental whilst X & Y are absolute  -- but that did take me a while

29

General Mach Discussion / Re: Simple radius cutting - isn't !

« on: July 19, 2020, 05:31:48 PM »

Above and beyond with that response Graham  -- thanks.
As it happens I am familiar with the concepts of tool offset though I haven't previously handled it in G-Code -- I recently made a small box with M. C. Escher Lizards and some Initials inset but that was on a Roland MCX-20 which takes .DXF files. The letters and Lizards had to be cut out using an outside offset and the box lid with an Inside offset.

Using G-Code is a new experience for me but the concept of tool positioning is not.  There was no way you could second guess my past experience and your very good explanation is greatly appreciated.

How I hadn't noticed [ CV Mode ] is beyond me     but oddly enough - like so many options in Mach3 - when I click on it nothing seems to happen  ie. the green light doesn't change. It may well be that I'm in some state that precludes a change.  Notwithstanding that, you'll understand that I've done more testing and have been successful in 'drawing' the shape along with a second trace showing the offset. I also noticed that the feed-rate did change as the pencil approached each bend. From that I presume that CV is 'Off'.


I had a number of 'issues' which had to be addressed. Primarily to do with initial positioning of the second (offset) trace. My first attempt was to simply duplicate the code from N230 to N320

Code: [Select]

%
O0000     (Radius test)

N100 G17 G21 G54 G40 D0
N230 G00 X-100 Y50
N240 Z-32
N250 G01 Z-33.5 F250   (no tool Comp)
N255 S2000  M03
N260 Y-70 F3000
N270 G03 X-80 Y-90 I20 J0
N280 G01 X80
N290 G03 X90 Y-80 I0 J10
N300 G01 Y10
N310 G03 X50 Y50 I-40 J0
N320 G01 X-100

N330 G17 G21 G54
N335                                       (8Ø tool compensation)
N340 G00 X-104 Y54 Z-32
N350 G01 G42 P4 Z-33.6 F250
N360 X-100 Y-70 F3000
N370 G03 X-80 Y-90 I20 J0
N380 G01 X80
N390 G03 X90 Y-80 I0 J10
N400 G01 Y10
N410 G03 X50 Y50 I-40 J0
N420 G01 X-130

N530 M05
N540 G40
N550 X200 Y100 Z0

N560 M30
%

... but I soon found that I also needed most of N100 as well. I then found that the compensation didn't work correctly since I'd left N340 as X-100 Y50 and once I'd changed that to -104 and 54 line N360 needed X-100 (this wasn't needed in the first run because it was Modal).
I did try to insert G42 P4 at line 335 but that gave me other errors -- I still can't fathom why - or how to circumvent them, though I suspect that there is a way to account for a tool offset without manually specifying a new X and Y in line N340.

30

General Mach Discussion / Re: Simple radius cutting - isn't !

« on: July 19, 2020, 11:11:05 AM »

Well, after many more 'tests' I seem to have solved it.
New Code :

Code: [Select]

%
O0000     (Radius test)

N100 G17 G21 G54 G40  D0
N230 G00 X-100 Y50
N240 Z-27
N250 G01 Z-29 F250
N260 Y-70 F3000
N270 G03 X-80 Y-90 I20 J0
N280 G01 X80
N290 G03 X90 Y-80 I0 J10
N300 G01 Y10
N310 G03 X50 Y50 I-40 J0
N320 G01 X-100
N330 M05
N340 X200 Y100 Z0
N350 G40
N360 M30
%
Now all I have to do is figure out tool radius compensation

This exercise has at least taught me where to get the parameters for G54 etc.  but I'm still ignorant as far as 'CV' is concerned.