Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: terry1956 on September 16, 2016, 03:42:03 PM

Title: Help needed v carve to mach3
Post by: terry1956 on September 16, 2016, 03:42:03 PM
Hi chaps.I have a problem.my mill cuts find.on checking the movement of the tool using test g code and also the mach software,all is ok. The mill is set for mm. I made a simple square design using v carve.but when using the g code.the mill cuts far to large.both the mill and the g code is set to mm.
Can anyone help me out here.
Title: Re: Help needed v carve to mach3
Post by: Ford Prefect on September 16, 2016, 04:11:39 PM
how much too big? like 10 times?

I suppose you have tuned your machine?
Title: Re: Help needed v carve to mach3
Post by: terry1956 on September 16, 2016, 04:16:02 PM
Hi.yes the machine is tuned. Parts come out around 150% larger
Title: Re: Help needed v carve to mach3
Post by: Ford Prefect on September 16, 2016, 05:52:55 PM
is it all the same for all axis?

I am asking because I get confused sometimes, it goes like this

open your tape measure and pull it out for 1/2 a meter and it says 50 but its not 50mm its 500mm,

my guts say check your dimensions in the drawing programme
Title: Re: Help needed v carve to mach3
Post by: olf20 on September 16, 2016, 07:22:46 PM
Another thought is; what post processor are you using in Vcarve?
olf20 / Bob
Title: Re: Help needed v carve to mach3
Post by: pugman on September 17, 2016, 03:56:49 PM
hi, I posted the code using Mach2/3 ATC Arcs (mm)(*txt)       I have know idea what is going wrong here.
Title: Re: Help needed v carve to mach3
Post by: garyhlucas on September 17, 2016, 06:38:55 PM
The answer is right in the g-code. Is the code it producing the same size as the part you drew? Have you put a tool diameter in v-carve and are you cutting inside or outside of a profile?
Title: Re: Help needed v carve to mach3
Post by: pugman on September 18, 2016, 04:05:08 AM
h. I ran the g code in an editor before posting to the machine. the cuts are inside and yes I did input tool diameter into vcarve. could it be the way that mach is reading the g code ????
Title: Re: Help needed v carve to mach3
Post by: Ford Prefect on September 18, 2016, 05:40:58 AM
your not giving enough info for us to make any judgement!!!!

Saying it doesnt work is not enough!

Please tell us in detail what calibrating you have done. :)

have you looked at utube for help?

try looking at this video please https://www.youtube.com/watch?v=LRagjLewSJg

sorry if I come across strongly but unless we have decent info we are just guessing
Title: Re: Help needed v carve to mach3
Post by: terry1956 on September 18, 2016, 05:50:25 AM
Hi. I have used the mach 3 software to scale the stepper motors, and they move the correct distance on each axis. I have reduced the motor accelerate, I have checked that the mach 3 is in the mm setting.i have made sure that the correct ccutting tool dimensions are bring used.
I have used the road runner demo and it cuts correctly. But when I try to cut with the vcarve g code, the machine trys to cut to large a work and I need to end the process as the machine runs off the bed.
I have ulso used Cam editor to read the g code produced by vcarve and the diameters come out correctly.
And you are not coming on to strong, I am glad of the help.
Title: Re: Help needed v carve to mach3
Post by: Ford Prefect on September 18, 2016, 08:38:47 AM
fine :)

Did you follow the video, and used a measuring stick on the tip of a vbit? this is important!

dont forget "50 on your tape measure is 500mm"

if you did follow this video

then its the problem is in v-carve, make sure that one of the first 20 lines in the finished gcode from V-carve has a G21 command (for mm) (G20 for inches)

the G21 line in my gcode looks like this

N160G00G21G17G90G40G49G80

without the colour red

if its there in the finished gcode then check again the distances again in v-carve

50 on your tape measure is 500mm



Title: Re: Help needed v carve to mach3
Post by: terry1956 on September 18, 2016, 10:02:40 AM
Thanks.Will take a long look and get back