Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: dodiano on October 23, 2011, 07:33:40 PM

Title: Problems with Measurements when cutting with MACH 3
Post by: dodiano on October 23, 2011, 07:33:40 PM

Hi Guys,

I use Autocad for my drawings and save them in DFX and convert them with Lazycam! Now I have been having toruble with measurements ... Normally one side is always off not sure why? For example I cutted a rectangle out of Acrylic which measured 2 Inches in Width x 10.75 in height! The 2 inches came out perfectly cut but the 10.75 inches measured like 10.85 and I have no idea why???? I seem to have this problem with certain drawings in Autocad but not all... Any ideas... Also another issue I have...

I make 1 piece which is a Left side for a project which has a hole on one side... I then use the mirror function in Autocad and mirror that same piece so I can have the hole as a right side for my project... Th thing is that when I convert the DXF file from Autocad mirrored and I convert it to Mach3 and then cut the part out the Hole piece is like 1/16th smaller ... Any ideas why??

Thanks for the help!

Roberto

Title: Re: Problems with Measurements when cutting with MACH 3
Post by: RICH on October 23, 2011, 08:24:42 PM

Quote

I seem to have this problem with certain drawings in Autocad but not all

Post the dxf file and also the gcode file from LC.

Quote

Hole piece is like 1/16th smaller

Post the dxf file before mirroring it and also the dxf files for both sides.

How much backlash do you have on each axis?
I really don't think it's a Autocad or LC problem.

RICH
 

Title: Re: Problems with Measurements when cutting with MACH 3
Post by: BR549 on October 23, 2011, 08:35:34 PM

Double check your acad draw for errors. Check all Dims

Double check your Gcode output from Lcam , Do the math verify the cut sizes are correct in the Gcode

Finally IF those 2 check out it only leaves the machine. Check the couplings and check for lost steps on the axis.

Just a thought, (;-) TP

Title: Re: Problems with Measurements when cutting with MACH 3
Post by: dodiano on October 24, 2011, 12:35:51 AM

Will check my dimensions and will do the maths on the G-CODE thanks for that! And if not is my CNC machine is just weird cause there are certain files I cut first cut is great second on is like 1/32 smaller ?? But just certain files specially those I have mirrored? Will post codes tomorrow!

Regards,

Roberto