Collaborative work for an open project (3D printer)

fma

Hi!

I'm using Onshape for a few months, now, as a maker, for fun personal projects, and I recently made a simple workshop for a few people in the LOG, a french hackerspace based in Grenoble (https://www.logre.eu/wiki).

3 years ago, a nice project has been launched In this hackerspace: a 3D printer, based on the P3 Steel. A great job has been made by many people to build a really good printer, and we are about to release the 3rd iteration. This printer is called 'LOGresse': https://www.logre.eu/wiki/Logresse/en (more details on the french page). Almost 150 machines where built.

Until now, all drawings have been made with Librecad, as all parts are laser cut, so 2D only. Today, we would like to maintain this project using Onshape, mainly for the collaborative feature. This will also allow us to build a 3D model, which is very usefull to check that all is fine. A friend started to import DXF, and build the 3D model: https://cad.onshape.com/documents/9fcacffa14bbcb794a372061/w/1cf9683d04a93c666f667b13/e/36fc3009022fd5a8933eb5f4

But we have to admit that we don't know how to manage this collaborative work! Here a a few questions:

- is it better to split the project in many sub-assemblies, so different people can work on different parts without collision?

- how to create usefull Mates for assemblies?

- how to organize the workspace? Is it better to have PartStudio next the the matching assembly? Where to put proteins (gears, bearings...)? How to use clever directories?

- when should we use branches? How to manage them without collisions? How to name parts?

- as said, the project is mostly laser cut based; are there some method to create/manage such parts? For exemple, I plan to write a FeatureScript to create the M3 nut cut used everywhere for the assembly. Are there other clever tools I could make to make the work easier? Should we mostly work on sketches, or on 3D parts? I have the feeling that 3D tools are better (fillets, for example)... Are there some better methods for the assemblies?

- as DXF imports do not generate usable sketches, we plan to correct them; any advice to make the work easier? FixDXF script is great, but the new sketch is not editable. Is there a build-in Onshape feature coming soon for that?

- how to create and maintain a good documentation, as it was done with Solidworks/LibreOffice? Are there some nice tools in Onshape or as third party?

If such public collaborative work has already been made, we would be very interested to have feedback.

Thanks for your help.

john_mcclary

With OnShape you don't have to worry about multiple people working in the same part or assembly. In fact it is encouraged.
So don't split the document because multiple people work on it.
You can pretty much ignore the fact others are working in your document.

Everybody has their own opinions on how to organize a document. So you may want to experiment a little and see what works best for you.
Here is a discussion on orgonization: 
https://forum.onshape.com/discussion/comment/27863#Comment_27863

What do you mean DXF import does not generate usable sketch?
My testing has been successful so far. Can we seen an example of a bad import?

How to create useful mates in an assembly. That will depend on your design intent. There are many ways to approach the same task in CAD.
A rule of thumb I try to stick to is:

Try to lock all the degrees of freedom with the fewest mates as you can. (Fasten and group are the best for this)

Try to avoid parallel and tangent mates whenever possible. (Parallel mates have their place, but they tend to get over used because they mimic traditional CAD mating practices. OnShape has much more powerful mates to use, so try to avoid parallel in favor of a single fasten or slider mate etc. Tangent mates also have their place, but in all CAD I have used, they tend to be wonky and flip to the opposite side of the circle sometimes)

Always mate to adjacent parts whenever possible.
Sound's obvious but I see people try and parallel mate foot pads to other foot pads on the opposite side of the machine. Their logic is they want them to move together. But if you ever want to offset a foot, or remove it, you may have to re-mate all the parts in the assembly you mated to that foot pad. It would be better to mate each foot pad to the frame member it is adjacent to. That way everything moves in a way you would expect if you stretch or shrink the frame work.

If you model many parts in one studio, use group mate and select everything in the studio. Group keeps track of each part's position relative to the origin in the studio. So if you make a change in the studio it will update in the assembly as well. That way you can mate many parts with just one mate. (Perfect for weldments)

Documentation. That is going to be up to you. OnShape has drawings, and BoMs that you can export as PDFs or spreadsheets. But you will need to use your favorite Office product to do the rest. (Google Docs, MSOffice, LibreOffice etc.)

Hope this helps

fma

john_mcclary said:

With OnShape you don't have to worry about multiple people working in the same part or assembly. In fact it is encouraged.
So don't split the document because multiple people work on it.
You can pretty much ignore the fact others are working in your document.

I understand that Onshape allows concurrent editing, but from a functional point of view, this can lead to bad things... Like for software, I guess that interfaces should be well defined. Or do I miss something?

Everybody has their own opinions on how to organize a document. So you may want to experiment a little and see what works best for you.

Here is a discussion on organization: 
https://forum.onshape.com/discussion/comment/27863#Comment_27863

Thanks, I'll look at this thread.

What do you mean DXF import does not generate usable sketch?

My testing has been successful so far. Can we seen an example of a bad import?

Have a look at this thread: https://forum.onshape.com/discussion/4616/import-dxf-with-points-joined

Thanks for advices about Mates; I didn't know that groups maintain PartStudio relative positions; that's nice!

john_mcclary

ah so it's all about the DXF coming in un-constrained then..
That's pretty much expected, but yea OS is lacking in window selecting endpoints for faster constraining. Sorry

But at least all you have to do is constrain a drawing, rather than re-drawing it.  

When you working with other's in the same document you can see where there are, and what they are doing. So try to work around a different area if possible. Double click their picture on the top of the screen and peek at what they are doing once in a while to make sure you're not working on the same thing  

Otherwise the interface has proven pretty reliable so far when I tried collaboration with someone. OnShape creates each feature in order on the tree, so even if you collide, it may be as simple as dragging your feature before his. (In the case of you both sketch on the same surface and they finish first, thus destroying your reference geometry). Like I said, the updates are live so you will see a collision within seconds and can usually fix it without much thought or effort.

fma

Yes, I had a look at the collaborative editing, and it is very powerfull!