Is Path workbench up to the task

[joaopcrodrigues]

Hi,
I've recently build my cnc machine and I need to mill a wing like object out of a piece of wood.
My firsts tests with Path workbench and a simple object were not very satisfactory, and I was wondering if it is up to the task for more complex things like a wing?

Best regards.

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Screenshot from 2019-03-23 02-26-22.resized.png (92.16 KiB) Viewed 2819 times

[Kunda1]

mods, please move to Path subforum. Thanks!

[triplus]

Hi @joaopcrodrigues

Please, first explain what was not satisfactory in your basic use case test. As expecting things will improve in more complex use cases, they won't. From the description, we will likely be able to figure out, if it's due to Path or things like build quality of your machine. Or if something else it at play, that could get improved in the future. In addition, and looking at the attached image, if you run Part -> Check Geometry on Wing Solid, are the results OK?

[joaopcrodrigues]

Hi @joaopcrodrigues

Please, first explain what was not satisfactory in your basic use case test. As expecting things will improve in more complex use cases, they won't. From the description, we will likely be able to figure out, if it's due to Path or things like build quality of your machine. Or if something else it at play, that could get improved in the future. In addition, and looking at the attached image, if you run Part -> Check Geometry on Wing Solid, are the results OK?

Hello,
I'm new at Cad and CNC (all started in september 2018) and this is my first project. Now I seem close to my primary goal yet, after all the struggling and frustrations while learning FreeCad and building a machine from scratch alone, the Path worbench did not perform as I was expecting, most probably because I'm not using it correctly, it makes me doubt if I should use other software like Fusion360. The main reason for using FreeCad is because I run Linux and I was avoiding having to use Windows and proprietary software (but I will if necessary).

Regarding my machine, it seams pretty solid, (or at least enough) and working, I just haven't decided yet if I should keep using a threaded rod or try a driven belt to move X and Y axis.

Regarding the geometry check, yes, it was ok, o errors.

[sliptonic]

the Path worbench did not perform as I was expecting, most probably because I'm not using it correctly, i

You're not giving us much to go on here.
What were you expecting? What did you get?

I have quite a few videos in my youtube channel dedicated to Path workbench. I would suggest you get started there to get familiar with the workflow and capabilities.

If you're talking about shaping a wing, you might be expecting true 3D operations. Path can barely do this and it's still set up as an experiemental operation. Even if it was working well, 3D sculpting is a more advanced machining operation. I suggest you get familiar with the process and with your machine by focusing on true 2D and 2.5D operations first.

[chrisb]

I just haven't decided yet if I should keep using a threaded rod or try a driven belt to move X and Y axis.

I would always go for the threaded version. On a mill you face counterforces which a thread can hold, but I doubt a direct belt driven milling head can do so. It might seem intriguing when you have seen a 3D printer, but that works almost at no counterforce.

[schnebeck]

I've recently build my cnc machine and I need to mill a wing like object out of a piece of wood.

While I can only estimate the size of your machine it looks a little bit weak for its size, no rails, no ballskrews - more like a big 3D printer but not really suited for milling. Maybe softwood and engraving works but more...?
Put a suitcase scale around your milling spindle and pull with 50N (5kg) in X and Y while drives are in control mode. Then read the deposition of your endmill from a base mounted dial gauge. If its lower 20 1/100mm its fine and your machine is suited for hardwood, too. Otherwise your machine does not withstand the milling forces of harder materials and your endmill will broke or the results look bad. What is the base size of your profile system? What cnc controller do you use?

HTH

Thorsten

[joaopcrodrigues]

the Path worbench did not perform as I was expecting, most probably because I'm not using it correctly, i

You're not giving us much to go on here.
What were you expecting? What did you get?

I have quite a few videos in my youtube channel dedicated to Path workbench. I would suggest you get started there to get familiar with the workflow and capabilities.

If you're talking about shaping a wing, you might be expecting true 3D operations. Path can barely do this and it's still set up as an experiemental operation. Even if it was working well, 3D sculpting is a more advanced machining operation. I suggest you get familiar with the process and with your machine by focusing on true 2D and 2.5D operations first.

Hello,
A actually saw most of your videos, very helpful, and I even bought your book three months ago.
You just gave me the answer (not the one I wanted to hear) to my question, "If you're talking about shaping a wing, you might be expecting true 3D operations. Path can barely do this and it's still set up as an experimental operation" It's what I was afraid of... but at least a got a pointer. Unfortunately I'll have to try other cad programs (I hope fusion360 will do this, got a lot to study and learn... again... at least Freecad gave some basics).

I'm leaving you the link to a stl file (2.6 MB, too large to attach here) that is one example of what I wanted to achieve to mill with my machine and with FreeCad. Feel free to try and if by any chance you can make it work with FreeCad or other open source programs and generate a usable G-code, please let me know.
https://drive.google.com/file/d/1qlkoev ... sp=sharing

Best regards.

[routalot]

This project isn't too far removed from some things that I have in mind for the future.As a result I got a bit curious and spent a little time playing with a few things.I downloaded the .stl you gave the link to and had a bit of a learning process to go through regarding working with meshes.I learned that something like 25,000 normals needed flipping and having found haw to convert to a solid,I found a huge number of facets and it took a lot of time to get anywhere.Did you consider using lofting to create less busy objects?

To save some time and establish whether the process of machining might be viable I swept an Eppler section along two 3D curves to create an trial object.With the object created,I had a play with several alternative ways of machining the upper surface and I could generate a toolpath.It isn't too useful for real life use as the stepover is large to save computing time.The issue I would need to overcome is the tendency to plunge to the lowest point when the tool passes beyond the edge.I expect it would be possible to create a horizontal surface out to the stock boundary to avoid this.If I were doing it for real,I would have to create several toolpaths at a number of depths and stepovers and then a final cut with a very fine stepover.If I had one wish for the Path module it would be for a means of establishing boundaries for different machining operations instead of being tied to stock size;come to that being able to model the stock a given size more than the periphery of the piece,instead of a rectangular block would be a huge help.

I hope the attached image file shows what I generated and is found useful.

[joaopcrodrigues]

This project isn't too far removed from some things that I have in mind for the future.As a result I got a bit curious and spent a little time playing with a few things.I downloaded the .stl you gave the link to and had a bit of a learning process to go through regarding working with meshes.I learned that something like 25,000 normals needed flipping and having found haw to convert to a solid,I found a huge number of facets and it took a lot of time to get anywhere.Did you consider using lofting to create less busy objects?

To save some time and establish whether the process of machining might be viable I swept an Eppler section along two 3D curves to create an trial object.With the object created,I had a play with several alternative ways of machining the upper surface and I could generate a toolpath.It isn't too useful for real life use as the stepover is large to save computing time.The issue I would need to overcome is the tendency to plunge to the lowest point when the tool passes beyond the edge.I expect it would be possible to create a horizontal surface out to the stock boundary to avoid this.If I were doing it for real,I would have to create several toolpaths at a number of depths and stepovers and then a final cut with a very fine stepover.If I had one wish for the Path module it would be for a means of establishing boundaries for different machining operations instead of being tied to stock size;come to that being able to model the stock a given size more than the periphery of the piece,instead of a rectangular block would be a huge help.

I hope the attached image file shows what I generated and is found useful.

Hello,
First of, thanks for your time looking at this.
My cad adventure started in September, so as you can guess I'm classified as a newb en terms of FreeCad. I started this with two goals, PlayStation rehab (got it), and I wanted to make an affordable hydrofoil set for my surf/kite-board. I spent 4 months trying to draw a wing foil with FreeCad, used all workbenches available and couldn't get the job done, to difficult to draw controlled and changeable aerodynamic shapes. Then I found an open source software made to make planes that I could use, export do stl and make small modifications with FreeCad (the file shared).
I was thinking on using Path WB to mill just the top surface of the wing, 1 millimeters to the edge border, flip the entire block (with markers to stay centered) and mill the surface to the edge only. The piece would be then removed carefully by hand from the block and sanded.
I wasn't counting on the PathWB not being yet ready for such a task.