I thought I would knock some dust off my drafting skills after a small chat with @captain_aggravated@sh.itjust.works
Seeing this image on the tutorial made me realize, FreeCAD seems to be a Technical Geometry Super-Suite. It makes sense that CAD would grow to include all of these things. But I thought sharing the initial perspective of some one who hasn’t looked at this stuff in about 18 years might be interesting.
Granted I’m not actually familiar with most of this stuff, and none of it from the POV of FreeCAD. If this can deliver 10% of what I’m looking at, I’m in for a treat.
Can it export STL/3MF without making all the circles low poly yet?
Last time I tried it freecad was not usable for 3d printing because it doesn’t export properly.
With the naming bug that still exists too I found it basically unusable even for basic parts. It feels like going back 20 years compared to fusion 360.
I’ve used it for making models for 3D printing for about 5 years, never seen that issue
Strange, when I looked it up at the time there were a bunch of suggestions for defaults to change and stuff to try and solve it.
You can print circles and not have them come out with flat faces instead of an actual circle?
So I guess it’s only an arc and not a full circle, but I had no problem making this curved sanding block in FreeCAD.
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Have you tried using the mesh workbench rather than just exporting as STL?
Yes. I just did a few days ago actually. Made some 4 mm diameter washers, they look perfectly round.
STL is a total abnormally and a piece of shit of a format that doesn’t actually represent 3D objects very well and has a ton of issues when it comes to sharing. Unfortunately we’re stuck with this shit format and Autodesk with their Tinkercad seems to want to keep pushing it because as long as we use this crappy format we’re forced into sharing and collaborating inside their platform - that at some point might require a subscription.
Completely agree about STL, however, I cannot for the life of me understand why 3MF isn’t a binary format.
It has all these big tech companies behind it, and they landed on incredibly short sighted mistake of making the format human readable, instead of providing good tools for reading and modifying the binary format.
Compressing the human readable content is fine for reducing storage size. But de/serializing the XML is going to be at least 3 orders of magnitude slower. Given a sufficiently large file, the difference would be waiting 30 seconds, vs a barely noticeable 0.3 seconds.
What isn’t variant of XML these days? I know, it’s bad but it’s what it is.
XML isn’t as common as one would think. It’s been steadily decreasing in popularity and use. It’s a very verbose format that is suited to enrich a larger set of data, such as HTML documents. For data heavy documents where, it’s a particularly bad match, as you end up using as much text for annotation as the data itself.
Using XML for 3MF is IMHO a technical cop-out, where you don’t really want to solve it “correctly”, so you go with something that is “good enough”. With XML, you know it’ll be able to encode anything, be human readable, and have existing parsing libraries in pretty much any programming language and standard libraries. So, it makes sense. However, if you’re creating such a format, the least one should do, is write a sibling standard for how to directly binary encode the data. This isn’t a hard thing to do. It just need a standard for how to do it, so everyone agrees. Here is an example online on how a rudimentary implementation could be done for OBJ files, but the principle is the same. That way you could chose to export either as 3MF or 3MFB (for binary), and as long as your slicer, and what not, can decode it, you’re good.
The hard part of 3MF was all the great work in standardizing what, and how that is represented.
I noticed a similar problem importing step files… I no longer had circles, I had nonagons… I would love to delete my windows vm that only exists for fusion 360.
If you are comfortable with all your models being available for download and some wonky Terms of Use that may let random internet people profit off your designs but not you, then OnShape in a full-screen browser feels about as good as F360 does. I guess you could also pay for it, but despite finding it pretty nice, I am iffy about paying Solid Edge prices for something browser based. I understand SolidWorks has slapped together a browser version as well, but nobody likes it.
Linux wise, there’s just not much outside FreeCAD and SolveSpace. BricsCAD is an okay evolution of AutoCAD, and VariCAD is a less good one.
I may have done a longer writeup than anybody needed the other day.
I have tried out onshape and it is a pretty functional fusion replacement, but I really don’t like the idea that the models I make can be used (or even just sold) by others commercially. I’d be okay with it if the free version just gave all models made with it an open license that barred commercial use entirely, but banned for me and open for sale by others is pretty dirty imo.
The sense I get is that it is more lazy than anything. The verbiage feels like the fact that designs were public documents was tacked on last minute to satisfy some desire for market segmentation or to create a parts and design library to draw traffic. It would make sense that the company hosting the software would not want the headache of being unable to use your stuff commercially or even of parsing what they could use, since in some sense they always are using everything commercially. Refusing the to thread the needle with their verbiage, though, has left a situation where the Terms of Use say clearly that (1) a design is Content, (2) a free user’s Content is a public document, (3) a free user cannot use their own public documents for commercial use, and (3) a free user grants EVERY OTHER USER a license to sell their public documents.
The only possible wrinkle is that the ToU distinguish between a “Customer” and an “End User,” so maybe you the customer can grant you the End User the same commercial rights that Joe the slightly shady CNC machinist in Peoria has when he downloads your widget to fabricate and sell. Something tells me that PTC’s license compliance folks don’t interpret things that way, though.
Last time I tried freecad, the geometry solver was incorrect, so it would sometimes create two (or more) shapes from a fully constrained part. Since learning about openSCAD, I’ve seen no reason to give it another try.
When I tried it like 7-8 years ago it crashed pretty much every time I touched a constraint. Was I probably doing something very wrong? Yes, but that made it pretty impossible to learn. Opposed to Fusion360 which just yells at you when you do dumb shit.
Sounds like it was only five years behind SolidWorks. The CAD program with one level of Undo, an unreliable Revert option, and active hostility toward incremental saves. It was great for machining because every change was about as permanent and slicing up actual metal.
I don’t know the first thing about CAD, but lmao.
Not the first four letters that came to mind.
Yes, I’ve 3d printed circles from freecad without issue. There are some precision options when converting to a mesh. I always set them to the tolerances of my 3d printer.
Overall, it still has a lot of rough edges though.