My CAD experiences

[_big_]

I'm looking to find a single solid modeling tool to drive my 3D printer and CNC milling machine.

Currently, I use OpenSCAD for the the 3D printer and then Slic3r for CAM. OpenSCAD does not do GUI based modeling/developing. Its a scripting language that describes the 3D solid. OK for simple things, but it becomes cumbersome for more complex objects.

I use CamBam to drive the CNC milling machine. CamBam is more of a CAM program with a very limited CAD modeling front end. Based on the traffic in the forums, it seems to be somewhat abandoned.

I've used Sketchup a fair bit. And find it to be great for developing and visualizing just about any 3D object. I've used it on a welding table, a golf bag rack and even a rather complicated theater room in my house where it was critical that some cabinets fit in a tight location. For the most part, I haven't found any glaring missing features in the free version.

Ideally, I would like to use Sketchup to develop the source 3D model and then some ancillary CAM tools to drive the 3D printer and CNC milling machine.

However, in the past when I've tried to feed a Sketchup developed .stl file into Slic3r, Slic3r throws up. People in the forums say the Sketchup generated .stl files are a nightmare. I haven't tried it lately, and perhaps Sketchup has cleaned up their .stl output?

I've looked for CAM tools to use with Sketchup, but this too looks dodgy to me. Free software of course. I haven't actually tried any of the tools.

Autodesk has a free version of Fusion 360. And it seems to be quite popular. It certainly claims to have a ton of capabilities. I've seen some impressive 3D modeling results.

So, I gave Fusion 360 a try. Spent the better part of a week at it. For sure Fusion 360 is full of quirks. And you need to train your brain to think about the world the way it does, and not the other way around. I actually managed to get an .stl to render as expected on the 3D printer. But at the end of it, I've concluded that Fusion 360 is more of a 3D solid capturing tool as opposed to a 3D solid developing tool. It doesn't seem to snap to geometry. And the measuring tool in my opinion is peculiar at best. For my design style I like to develop some dimensions and essentially "enshrine" these dimensions in the model. With Sketchup, its generally easy to go back and measure dimensions. With Fusion 3D, I find it difficult to know you're really measuring what you think you're measuring.

So I'm pondering my next move. Here are the possibilities:
-Go with Sketchup. I'd even be willing to pay $300 a year for it. I have some architectural projects I think it would be really good at. They'll let you try the full version free for a month. Good news is I wouldn't have to learn how to use the drawing tool. During the free month, give the CAM output tools a good try.
-Stick with Fusion 360. It seems to work for many people. Try to figure out how to make it work for my style. But I'm pretty skeptical this is going to get me what I want. I've been through it and just don't see a way for it to fit my needs.
-Give SolidWorks for Makers a try. Looks like you can get a one month license for $10. Bad news here is its a big learning curve. The Maker version might not have features I need.

So... looking to the world wide web for opinions...

 

[jwmelvin]

Get your mind around Fusion. It’s pretty good really.

 

[TomWS]

I've used Sketchup since it first came out, but you're right, STL Mesh they do not do well. I was recently surprised, as I try my third attempt to use FreeCad constructively, that the latest version will output an STL Mesh directly from the Part Design Work bench. I've imported into Chitubox without any problems. It wasn't terribly complicated design, just a trial run, but I was surprised how easy that step was.

 

[_big_]

I've used Sketchup since it first came out, but you're right, STL Mesh they do not do well. I was recently surprised, as I try my third attempt to use FreeCad constructively, that the latest version will output an STL Mesh directly from the Part Design Work bench. I've imported into Chitubox without any problems. It wasn't terribly complicated design, just a trial run, but I was surprised how easy that step was.

I tried FreeCad a while back. Thought it was weird and all chopped up into different work benches. Gave up. The whole constrained 2D thing is similar to Fusion 360. While I can see how the constraint business could be useful, it definitely takes some getting used to.

 

[jwmelvin]

SketchUp uses constraints, it just applies them implicitly rather than Fusion, where most must be explicit.

 

[TomWS]

SketchUp uses constraints, it just applies them implicitly rather than Fusion, where most must be explicit.

That's a good point. I'm currently working on a jig design in FreeCad and by selectively applying constraints and leaving the rest free to move, I can move things around and Freecad keeps all the parts connected so I can mess around with placement before I start fixing positions. So far this has been pretty handy.

 

[addertooth]

I read these postings about CAD/CAM and get concerned. I have considered getting a 3d printer, but there seems to be a bit of learning curve to the products. I used CAD back in the early 80s (when it was a new thing for the home and small business user). The work I did was for Printed Circuit board design (OrCad, Tango PCB, Tango Route).

I hear the same tale told from different perspectives. The tale is summarized as "forget how you used to design things on paper, instead, you have to think like the programmers who wrote the CAD application". A well-written program allows input from the user, which is similar to the technique a human would naturally use. A solid application uses naturally understood concepts, and it translates them into complex actions (I mean it does run on a computer, right?).

For the record, I didn't have to know where in memory-space is my video card, nor did I have to translate my letters to ASCII code and poke them into screen memory to make this text. Nor, did I have to convert blocks of my text into an Ethernet packet with headers, packet type, and CRC trailer at the end. Those more complicated actions were handled from my simple and natural input, which was evolved from using a mechanical typewriter.

It may be time for CADware to evolve a bit.

 

[WobblyHand]

I read these postings about CAD/CAM and get concerned. I have considered getting a 3d printer, but there seems to be a bit of learning curve to the products. I used CAD back in the early 80s (when it was a new thing for the home and small business user). The work I did was for Printed Circuit board design (OrCad, Tango PCB, Tango Route).

I hear the same tale told from different perspectives. The tale is summarized as "forget how you used to design things on paper, instead, you have to think like the programmers who wrote the CAD application". A well-written program allows input from the user, which is similar to the technique a human would naturally use. A solid application uses naturally understood concepts, and it translates them into complex actions (I mean it does run on a computer, right?).

For the record, I didn't have to know where in memory-space is my video card, nor did I have to translate my letters to ASCII code and poke them into screen memory to make this text. Nor, did I have to convert blocks of my text into an Ethernet packet with headers, packet type, and CRC trailer at the end. Those more complicated actions were handled from my simple and natural input, which was evolved from using a mechanical typewriter.

It may be time for CADware to evolve a bit.

Although I share your view on this, I have to continue and get on with things. Although 3d printing isn't my primary motivator, being able to send designs to a 3d printer would be nice.

Towards that end, I have been learning FreeCAD. Is it a carefree experience? No. Have I had to bend myself and how I look at things, to be the same as the developers? Yes. Is it painless? No. Is it hugely different from learning any other software package? Sadly, no. Will it eventually be worthwhile? Think so. So, I am plugging away at it.

For what it is worth, one of the early video lessons (#6 by Adventures in Creation) on FreeCAD walks you through making a golf ball marker, really a guide for your marker, and then creating the stl file. He then goes and prints it. I thought that was pretty cool to have this capability at such an early stage of learning the software. I made the same stl file while following along.

 

[_big_]

Worked at the Sketchup approach. Signed up for the one month free. The good news is, Trimble gives you the free month without the usual credit card commitment defaulting to a sale if you don't cancel. Kudos to Trimble!

Managed to get a simple object to print pretty easily. There is an extension that checks to see if your solid is manifold, but it didn't find any problems with my solid. Encouraging, but I'll reserve judgement until I try it on more complex objects.

Looked deeper into the CNC/CAM output. There are a few tools, but they seem to be aimed at 2D router kind of things. There is an extension for outputting a DWG which can be fed into some CAM tool. Which could be CamBam. Something I know and like.

I've got a relatively simple machining project in mind. I think I'll develop the 3D solid in Sketchup, then tryout the DWG export path. See how it works with CamBam. I might try reading the DWG into Fusion 360 and see where that leads me.

 

[TomWS]

Managed to get a simple object to print pretty easily. There is an extension that checks to see if your solid is manifold, but it didn't find any problems with my solid. Encouraging, but I'll reserve judgement until I try it on more complex objects.

Try to sweep a profile along a path. It's easy to do in Sketchup, but sometimes leaves gaps in the surface that prevent creating a printable STL. The problem seems to show up if the path has rounded corners (a rectangle with fillets for example).