Hi Everyone,

I'm planning out the AC head for my 5 axis router.  A more practical question:  How do you do tool length compensation?  I have a manual spindle and I don't think it will be practical to have each tool be exactly the same length.  I do have a toolsetter so I can measure the length of each tool after changing. 

My plan was to use Solidcam or Mastercam to make toolpaths.  Does Mach4 have the capability to do RTCP?  If not, then how does toolpath compensation occur (and where?)  Is it in the CAM software then?  That would require regenerating the toolpath data each time you change tool and measure the new tool offset.  Not impossible but a PITA.

Thanks

Currently, Mach4 does not have kinematic.  I did see in the change log that it has been mentioned, no idea where kinematic are at for Mach4.
However, you may be able to set it up in CAM, just have your WCS correct in space with your fixture or platter.

I did see someone on here has a router  and they made their own kinematic macro to update tool position with each rotation axis move. 

Whats WCS?  (forgive my ignorance!)

Your Work Coordinate System; your work zero.  Make sure it is set up in CAM at the center of your rotating axis and that you have modeled the fixture you're using or your platter and place your work piece on the machine exactly as it is in your CAM model.  You also need to be sure to set your work zeros in the machine at the centers of rotation. 

AH, Yes, that makes sense for a trundle style 5 axis, I'm building a wrist-style. That's why i'm thinking that some real-time (or macro-able tool length compensation is needed)

My current thought is to build a jig where I can pre-set the toolheight precisely (not the easiest thing with a manual chuck).  Of course that complicates things because each tool has a different stick-out.

I'm a little confused now... You can just set a tool offset and call it up.  From what you're saying; by setting up a jig to get the tool stickouts the same.... you can just set a tool offset.
Are you needing to change the tool length offset each time you index one of the rotational axis?

No, this is the root of my question actually: for normal xyz coordinates, mach does the tool and fixture offsets.  Since the 5 axis toolpaths are more complicated, does mach still do the tool offsets for you or do you have to the post-processor/cam do it?

If the cam/post processor has to do it, you have to recalculate the toolpaths there for each tool after you measure its offset.  Not a huge deal, but not ideal.

One workaround i thought about was to use a jig to make sure the tool offset was the same as it was in the CAM software, basically mimicking what you’d have with ATC collets. 

But if mach was able to apply tool offsets in 5 axis, i have to do nothing  extra

You could probably write a macro to adjust the tool offsets to match what it needs to as far as your CAM setup. 
Again, what you're asking about is probably kinematics... which Mach4 doesn't have yet. 

https://www.machsupport.com/forum/index.php?topic=38140.10

I found this, I couldn't remember where I had seen it so I went searching.  Maybe reach out to him via personal message and see if he can chime in here.

we now build also 5 axiss heavy duty cnc  with mach
this days im working on the kinematic TRCP
when its will ready i can show
but there one more point we need consider ,our c axiss cant rotate without limit,so me need always calulate whice
side arive (there several HSD 5 axis head that can rotate without limt but there life time very limit ,after few years the circle contactors finish there life)

for sure the kinematic trcp its external application (im use c#) with  3d geomatric calculation
i already have many external pp like this ,but what i do its that user not need real run pp
i make buton that when he click on it he just run the c# appliction that do all chnges and with API load the nc direct in mach