I'm not really in a position to do any testing on hardware right now (I no longer work in a router shop.) but I can offer links to some G-code that I used in the past to help with testing the circular arcs tool planner when it was being developed. They are some 2.5-D V-groove engraving tool paths. They are in inches and need to have approximately +/- 0.003 of precision in the movements to look good. The first file is only XYZ moves, the 2nd file has XYZW to run a 2nd engraving spindle on a 2 headed router.

 

​​​​​​​ 

djdelorie wrote:

As the originator of this request, I've left my feedback in detail elsewhere, but let me summarize my request for this thread: After an hour or more of spiral carving with Fusion's linuxcnc postprocessor, I end up around A556200 (for example), then Fusion does G0 A0 to "reset" the rotary for the next op.  That takes many minutes of high speed spinning, and is totally unneeded.  I would like to skip this massive unwind.  This is a common complaint online, and the usual response is to use G10 to change the WCS offset before the G0 A0 but that has its own drawbacks.  Doing something similar in the G0 itself would be much more consistent across the machine's operation.  Yes, WRAPPED_ROTARY, but there are times when you don't want to use that.
 
 

Don't expect the standard LinuxCNC postprocessor in Fusion360 to be 100% compatible. It was created by people unfamiliar with LinuxCNC and who don't respond to error reports—this is a common problem with some basic HSM posts. This is especially true for the LinuxCNC post for turning—it's completely unusable without modification. 

To work with the WRAPPED_ROTARY function, the post needs to be modified so that the A-axis output is in the range 0-360 and the sign indicates the direction of rotation.
If you can't do this yourself, I can help with instructions later.

grandixximo post=346054 userid=3182
What I want to hear: does this behavior fit how your CAM emits G-code, would M26 default plus plain absolute output Just Work for you or would you need M27 sections, are there kinematic configs (coupled 5-axis TCP, gantry rotary, weird mappings) where you think this would behave badly, and do you have test G-code you would like me to run through it before merge.

Most CAM systems support any logic, but this needs to be configured in the post. This isn't done by default.
In any CAM, the postprocessor requires settings specific to the specific system. The fact that some users experienced problems with the rotary axis returning to 0 only means they didn't configure this setting and were using the wrong postprocessor. Having done this, there are no problems working with the current logic.

Regarding changes, I think the ideal change would be to simply add the ability for the WRAPPED_ROTARY function to automatically handle values ​​>360 in absolute mode.
However, giving users the option to toggle is also a good option.

But I don't understand the difference between m27 and the current wrapped rotary mode; as far as I understand, they are identical. Perhaps in this case, adding another INI line isn't necessary; adding wrapped_rotary=2 (type=2) will suffice, which will set the default mode for the rotary axis (m26 or m27).

I also believe that M27 is the primary mode for operation.
Reducing all transitions (in m26) is difficult to debug and lacks the ability to strictly define the direction of transitions >180.
Most 5-axis mechanisms don't have infinite rotation capability, and this is critical for them. Otherwise, additional functions have to be added to the post to separate movements >180 into two separate lines - that's an additional overhead.

Also, incremental mode is not recommended for use in CAM—it's prone to error accumulation during multiple short movements, which is what most programs consist of.

Hi Axemas,

really appreciate the steady progress you’ve been sharing, great demo video! It’s clear a lot of careful work is going into this, and it doesn’t go unnoticed.

The lathe features especially the polyline workflow alongside G71/G72/G73 look genuinely promising. That earlier preview video sparked a lot of anticipation on my side, and I’m still very excited.

Have you had any time to push this further since your last update, or did testing surface any tricky blockers? No rush at all just curious where things stand.

Thanks again for keeping NativeCAM moving forward. I’m really looking forward to the next steps.

greetings

Tom

PCW wrote:

You could, but you risk more damage if you accidentally connect the 5V  to a 3.3V signal.

Most likely the inputs of the 26LS32 has been damaged so the chip needs to be replaced.

This takes care and protection of the nearby plastic connectors with some kind of
insulation from the hot air gun heat (I typically use some paper sticky labels on
the green connectors)

OK. I won't risk.

I'm watching videos with notebook repairs, so i saw there how they protect the plastic parts from melting.
I hope i wont fail.

Fusion's LCNC standard post doesn't have a section for rotary-related M-codes, other than undefined clamp/unclamp.  Nor does it output incremental moves - appears everything is in G90.  So any rotary axis motion which requires switching between G90/91 won't be able to take advantage of ROTARY_MODULO = 1 without post modifications.

I looked at a few other Fanuc-based Fusion posts and none of them (including integrator specific posts) appear to have any M-codes or switch between type_1 and type_2 on the fly.  If newer controls are like my old Fanuc 21, you set the Type in the control and can't do anything on-the-fly.

I see you're still working on this in GH... I'll wait to comment more until the OP does some testing.

tommylight wrote:

Did you try unhoming and then homing the A axis?

 

Tommy - 

Re-homing a 4th axis means losing the work offset for that axis, even if its really close.  Unless you've got an accurate high-resolution encoder directly on the rotary axis (not just the driving motor), there's always a bit of 'ish' until you indicate the rotary axis in.

I've got a moderate resolution encoder on my servo, the 4th homes to index, and it's using a name-brand zero-backlash harmonic reducer... but it's rarely perfect. The only way to get (mostly) perfect is to home then indicate the axis and set the A-axis work offset... and not shut the machine off or re-home the axis.

None of that matters if all you're doing is OP1 parts, but if you're doing OP2 (or later) parts and previous features have to line up with new ones, a dead-nuts A0 matters.

antonyvm wrote:

I have abandoned the idea of setting up the Linux Cnc in the nuc.

Thank you,
Antony.

Probably a good idea. I had an expensive i7 NUC die before my very eyes and Intel made ridiculous offers under warranty that required me to invoke the Australian Trade Practices Act provisions to get a refund. 

Yes, coupling of inputs often means a missing ground.

Note the the field I/O is completely isolated from the
logic (5V side)

Kind of where my thoughts where - to the periphery of the board the wiring is correct - I've strapped field-V to the inputs (input KEFG connector). What you've described I can believe with a broken track/open circuit component on the board.

The easiest is master branch aka 2.10.