Machsupport Forum

Mach Discussion => FAQs => Topic started by: MADDesign on July 22, 2009, 11:32:44 AM

Title: CNC cutting inverted image
Post by: MADDesign on July 22, 2009, 11:32:44 AM

I'm having a rather frustrating problem at the very end of a long process. I created my design in Solid Works, then moved into Master Cam and now Mach 3. When I test the cutting pattern in Master Cam, everything looks correct, but when I go to actually cut out the design, it is perfectly inverted. Is there an inversion command that I'm missing?

I've noticed that in my g-code, all the x axis measurements are negative, which doesn't seem quite right. Also, I'm using a generic post-processor. Could this be the problem?

Title: Re: CNC cutting inverted image
Post by: BobsShop on July 22, 2009, 05:04:44 PM

Madd

Where are your X "0" and Y "0" set in relation to your mill.  Sounds simple enough, but all my pieces were being cut in reverse.  It wasn't until I started engraving words and letters that I noticed everything was being cut in mirror images to my designs.  Drove me Nuts.  I was doing a lot of screwing around with the ports and pins settings before this simple solution jumped out at me.

Bob @ BobsShop - still confused, but cutting in the correct order.

Title: Re: CNC cutting inverted image
Post by: MADDesign on July 22, 2009, 06:21:09 PM

Thanks Bob,

    Let me be a little more specific. As of 3 weeks ago I didn't know anything about cnc machines. I am teaching myself and I still need alot of specifics. When you asked "where are your X "0" and Y "0" set in relation to your mill?" did you mean in Solidworks, Mastercam, or Mach 3?

Thanks for your help.

Title: Re: CNC cutting inverted image
Post by: ger21 on July 22, 2009, 06:43:33 PM

Is it upside down or mirrored left to right? Typically, when users have the problem you're describing, they have their machine moving in the wrong direction. You can reverse an axis in Config >homing. Check the Reverse box.

Title: Re: CNC cutting inverted image
Post by: BobsShop on July 22, 2009, 07:28:17 PM

Madd

Look at the axis orientatiions in whatever cad program you are using.  This should be in the lower left corner of your drafting page
the axis on your mill should be the same.  In AutoCad it looks something like this
                             Y                                                                           
                             ^
                              l
                              -->X.

Many people (well, some and I was one of them) have their axis set to the RIGHT FRONT .
                                       Mill Column []
                                                                                              Y               
                                                                                              ^
                                                                                               l
                                                                                          X<-- RIGHT FRONT of table

Result is a mirror image of what was produced by your cad program.
Correct orientation is:
                                                  Milll Column []
                                 Y
                                 ^
                                  l
LEFT FRONTof Table      -->x   

Think of it sort of like you write (assuming you write left to right).

Not sure that is clear - and I may be all wet, but worth a shot.

Bob@ BobsShop

Title: Re: CNC cutting inverted image
Post by: j-sons on April 02, 2011, 07:47:05 PM

MADD,

How did you fix your problem?  I too am cutting letters and images backwards. Is it in mach3 on another program like
cad (inkscape) cam (cambam) ?

j-sons

Title: Re: CNC cutting inverted image
Post by: ger21 on April 03, 2011, 12:12:21 AM

Read my previous post. Your machine is running backwards.