5 axis tool offset

Hi,

I have a 5 axis homemade machine xyzab...I get gcode from CNCToolkit in Gmax....works pretty well other than tool offset...My linuxcnc is set up in Trivkins...My questions..  I believe there is a 5 axis configuration...

Is it very involved to switch?

Can tool diameter offsets be used?

Would it be better to try and modify CNCToolkit post to use tool offset? 

I am going off a surface...x y offsets I can draw...the biggest issue is allowing for tool diameter in adjusting z axis for b movents.

Thanks for any help!!

Rick

 

I believe there is a 5 axis configuration...

There are several.
So what exactly do you mean by 'xyzab'? That can mean a few different kinematics.

Like pic attached..

For this geometry there is this sim config in the current development branch:
github.com/LinuxCNC/linuxcnc/tree/master...ndle-rotary-nutating
I would suggest you have look at that before you start looking at changing over from trivkins.

You should also be able to install the kinematics component on version 2.9 using 'halcompile' (for which you may need to install the linuxcnc-dev package). The component can also be found here:
github.com/Sigma1912/LinuxCNC_Demo_Confi...ary/xyzacb-snrtr_twp

For your case, you would set the nutation angle to 90° and ignore the C axis. TCP will work just fine but the TWP feature will currently only work for the head rotation.

So IF I were able to get tool offset for 5 axis in CNCToolkit and run in trivkins.....would not having the TWP give same results?

Thanks for help here...I am a little over my head here but need to learn..

TWP is the 'tilted work plane' feature, you are likely after the TCP mode that keeps tool tip position stationary when the tool orientation and offsets change.
If your CAM is capable of handling tool offsets then you can keep using trivkins.

I am not sure if tcp will help here..see attached pic...maybe not clear but difference in green and yellow rectangle show difference between tool center and reusuting cut of a profile cutter where cutting edge is offset from center of tool..seems like b axis would need more z height to give correct cut on both sides of stock.
 

Removed your last post. You cannot just past images into the post like that you need to use the Attachment box.

I'm not sure what you mean but I'm also not a 5axis expert so somebody else might be able to say more.

Again..my apologies.. i am certainly no expert...just trying to find out if what I want to do is possible...Should I be asking in a different place?

Thanks

5 axis is certainly a bit off the beaten track. You might want to try on the linuxcnc discord server or on a forum that caters more to 5axis machining and CAM applications. I'm afraid I don't have any links for you though.