Path Profile Faces: 4th-axis integration

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Russ4262
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Re: Path Profile Faces: 4th-axis integration

Post by Russ4262 »

kkremitzki wrote: Mon Jun 24, 2019 4:14 pm Be careful offering such a solution as a workaround. If you put a file in a system-managed location it can break the system's ability to manage the FreeCAD package. Whenever the update comes around for the package it will want to install a file to a location that already has something there and will fail.
Thanks for the insight. So, in the temporary solution offered above, the user would need to revert the changes before performing a system initiated update for FreeCAD. … Or, not attempt the solution at all because it might not be an actual, temporary solution.

I appreciate the info,
Russ
Erich Schulz
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Re: Path Profile Faces: 4th-axis integration

Post by Erich Schulz »

thanks Russ

I am confortable with git and unix (but have never really used make)

I can give that a go but I was hoping that the build would be fixed... I'll see what happens in next day or two
somuch245
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Re: Path Profile Faces: 4th-axis integration

Post by somuch245 »

I'm trying to make wooden planter using 4 axis cnc router and I came across this software. I read that this software 4 axis is in experiment phase, what's the problem in actual run when X axis can't simulatenously move with Y axis?

I'm trying to make something like this
Image

Can this software make something like this properly?
If it can, how long it takes usually to make one? The planter inner diameter size is about 8cm (around 3.2")

Thanks!
Russ4262
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Re: Path Profile Faces: 4th-axis integration

Post by Russ4262 »

Welcome to the FreeCAD Path forum, Somuch245! We would be glad to have another FreeCAD user.

As for your questions, I don't think the 4th axis capabilities of the current 0.19_pre have had much testing. I have been the primary developer for the current 4th axis implementation and I don't even own a 4th axis machine! LOL. I do know there are users here in the forums that have 4th axis machines. I'm always up for technical and procedural input from experienced CNC users.

Looking at your image, as a novice in the field of CNC, I don't really have a good idea of a general work flow to produce such wooden pots. If I had a FreeCAD file with something similar to work and test with, I could better adapt the current 4th axis to fit the needs of 4th axis users. Looking at the pots, I would say the milling approaches would not be the same for each pot. The one on the left leads me to use the current 3D Surface multi-pass operation. The two on the right make me think one would need to create the simple design path, and then replicate it in an array fashion around the desired axis of rotation. I don't think FreeCAD is ready for this last approach - 4th axis is still in its infancy within the Path WB.
somuch245 wrote: Sat Feb 08, 2020 7:39 am I'm trying to make wooden planter using 4 axis cnc router and I came across this software. I read that this software 4 axis is in experiment phase, what's the problem in actual run when X axis can't simulatenously move with Y axis?

I'm trying to make something like this
...

Can this software make something like this properly?
If it can, how long it takes usually to make one? The planter inner diameter size is about 8cm (around 3.2")

Thanks!
Glad you joined the forum. Feel free to post additional usage questions. The FreeCAD Wiki is quite helpful, as well as FreeCAD tutorial videos on YouTube.

Russ
adamLange
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Re: Path Profile Faces: 4th-axis integration

Post by adamLange »

Hi Russ, Hi Somuch245,

I think I can help with making toolpaths for those wooden vases.

I've been working on an inverse kinematics solver and I've successfully used it to generate gcode for my 5-axis machine. There's a thread about the development it here: https://forum.freecadweb.org/viewtopic. ... cs#p367597 and a hackaday page here: https://hackaday.io/project/169499-solv ... h-modelica

The inverse kinematics solver can solve for n-axis simultaneous motion. The inverse kinematics solver is a server. To use it, you feed it tool targets with the tool tip position and tool orientation like these: Image

The inverse kinematics solves for the machine axis positions necessary to put the tool on the tool target and sends them back to the client. The inverse kinematics solver can be easily customized for any machine.

I'd love to help integrate this solver into the freecad path toolbench.

Adam
m0n5t3r
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Re: Path Profile Faces: 4th-axis integration

Post by m0n5t3r »

Those pots look very much 3d printed to me :)

Would it be possible to make them on a 4 axis router? maybe the leftmost one, but the center and right one would be really tedious (lots of features, deep trenches requiring most likely one of those conical endmills and possibly 2 or 3 tools so it doesn't take a month) and you'd need to find a wood that's as isotropic as possible (so some really dense hardwood not prone to chipping, or something resin stabilized - kinda hard to do on such a large object unless you machine out the interior first).
RatonLaveur
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Re: Path Profile Faces: 4th-axis integration

Post by RatonLaveur »

These vases are cool and all but indeed only with a conical end mill for 4 axis. 5 axis necessary otherwise.

But I am sure i cannot be the only one that for the second time on these forums some enterprising soul is proposing a real shot at 5 axis integration. I mean this is some real heavy stuff there. Need some noise about it ;)
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freman
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Re: Path Profile Faces: 4th-axis integration

Post by freman »

Hi,

I'm keen to see whether this solves my v-gouge problem, it seems like a good, simple test for 4th axis.

I have a manually adjustable spindle mounting which I have rotated 45 deg about X axis.

I figured that this should produce a 4th axis path with a fixed rotation of 45 and milling along X .

I'm probably missing something I need to do but it just looks like the standard way the 2.5D tools project the face down onto the plane perpendicular to Z and then drop down to that plane , ignoring the model of the part.

Something like this path but rotated is what I expected. Here with the width between the cuts indicates it is still calculating for the horizontal plane.

Am I doing something wrong or have I got false expectations of what it should produce?

Thanks.
Attachments
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nyles
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Re: Path Profile Faces: 4th-axis integration

Post by nyles »

I'm attempting something (I thought was) simple - a hex extrusion on an A axis. The top three facets work fine when I do a path pocket, and I can see the rotations and paths fine. However, when I try one of the 'underside' facets, the action happens on the opposite side of the work piece.

Any clues to convincing path to do the facet I'm trying to work on?

TIA

System Info:
Version 0.19
Revision 24276 (Git)
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Last edited by nyles on Thu May 27, 2021 12:46 am, edited 1 time in total.
Russ4262
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Re: Path Profile Faces: 4th-axis integration

Post by Russ4262 »

nyles wrote: Thu May 27, 2021 12:36 am I'm attempting something (I thought was) simple - a hex extrusion on an A axis. The top three facets work fine when I do a path pocket, and I can see the rotations and paths fine. However, when I try one of the 'underside' facets, the action happens on the opposite side of the work piece.

Any clues to convincing path to do the facet I'm trying to work on? ...
Good morning. Welcome to the forum!
You will find many helpful members here. Taking a look at your situation, I recreated a similar extrusion in Part Design workbench along the X axis. Upon attempting to Pocket that same face highlighted in your image, I confirm the same error. To my detriment the rotational features have a few bugs. I attempted the Profile operation and it profiles the correct face, but the depth passes through the object to the opposite face.

While the rotational features available in 0.19 are buggy, they are allowing us to get useful feedback and testing of both path generation and code structure. We are working to correct and reconfigure the rotational features for the 0.20 release.

I will see about fixing these issues should there be another 0.19.x minor release.

For the time being, if the ONLY error with the incorrect pocket paths generated is the 180 degree rotation error, this is a very simple fix manually in the g-code. Unfortunately the changes entered upon using the Inspection tool are lost upon saving because a recompute is triggered. However, finding the same rotation line, A59.999998 in the post-processed file can be changed to A240.000 (or whatever error angle + 180). Making this change will correctly index the part for that operation.

At the moment, I think the simplest solution is add another rotational property, RotationOverride, that would allow the user to enter a manual rotation angle to be applied during the operation, rather than using internal analysis methods in place. There have been a number of similar situations here in the forum where rotation is 180 degrees out of alignment.

Have a great day.
Russell
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