Centroid Community CNC Support Forum

I understand the Acorn can support 4-axis simultaneous motion. I do not fully understand how to take advantage of PLC inputs yet, but am curious if the controller can support 3 + 2 machining where the position of a 5th axis is controlled through Acorn via a PLC?

New guy here, apologies if this is not the right forum...

hello.
please describe what type of machine you have and what machining operation are you trying to accomplish

When I first read about the Acorn and noticed that the description included the word "PLC", I just assumed that my idea of a PLC was the same thing as the PLC in the Acorn. There is a difference. The PLCs that I use are configured by changing their ladder logic using PC based PLC software. The PLC, as used by Acorn, can also be changed by editing the PLC code using a PC, but not in the way that those who might have an off-the-shelf PLC would expect.

What I've found to work the Acorn when using an external PLC is to use the PLC to shape signals and to control signals that are either loosely monitored by the Acorn, or signals that are not even monitored by the Acorn (such as changing the way a servo's enable signal is generated, or cycling power supplies, or changing the polarity of servo fault signals when using servos from different manufacturers).

What I doubt would work would be to closely couple an Acorn controlled axis with an external PLC controlled axis. To me, that's why Centroid offers the Oak controller. Centroid has pushed the BeagleBone based controller much further than I thought possible, but there are practical limits to what we should expect from a $300 BeagleBone based microcontroller. Cutting a 3-D arc is a fairly complex operation. Expanding that 3-axis arc to a 4 or 5 axis arc adds an order or magnitude to the complexity.

I have a bed mill that I envision adding a rotary table or a tilting rotary table with a Tormach tombstone on the end to fixture multiple small parts. These parts are machined on all faces and have non-planar holes that can't be drilled without several additional fixtures and setups. The tilting table would support drilling the non-planar holes without re-fixturing just for the holes.

I answered CNCKeith's question prior to Mike's post, but I must not have hit "submit."

Mike, Thanks, I think I see what you mean. Last time I programmed something related to motion was many yrs ago in basic (not visual basic) and that's the last programming I did.

A bed mill with a rotary table is no problem for the Acorn and can be run in 1,2,3,4 axis mode in any combination.
Adding a 5th axis under CNC control with Acorn is not possible but is with Oak.