Fun with Inventor

The place we are ordering the parts from has a warehouse nearby, so materials normally ship within a day, but the person responsible for placing the order ordered the parts today, so I should have them by tomorrow. That said, I spent most of today designing the parts in Autodesk Inventor; I'm pretty happy to finally have an excuse to digitally model something that would actually be used. It was quite fun, although a lot of time was spent battling the lagging computer. I didn't bring my laptop to the lab, so I ended up installing Inventor on my secondary computer at the lab (since the primary broken one is being dealt with by IT). The computer, which was meant to be a server, has eight CPU cores and generally decent specifications, but its graphics card was made in 1998, which is hardly ideal for a graphical 3D application. In the end, it wasn't that much better than remote-desktopping into my laptop would have been. The design itself is fairly simple, as you might expect from a plate with a few holes and a rod with a few grooves:

The rod sits on top of the lower electrode; since they are attached through openings at the same height, the rod will have to push down on the electrode. Hopefully the friction there won't be too significant.

The current design for the plate. The green circle is the disk edge, the smaller blue circles are the relative size of the electrode, and the outer square is the window the disk has to fit through. I was planning on putting the small holes (for the fishing line) on the outside of the electrode, but there's not enough space there, so the line will have to go through the electrode.

I really love the whole paradigm around which Inventor works; instead of putting each piece directly where you want it to go, like in a traditional CAD or modelling application, in Inventor you just define the relationships between the elements to constrain them in certain ways. For instance, the small green circles you can see above (which define the fishing-line holes) can be freely moved around, while the other three holes will automatically mirror across axes, the dimensions recording the holes' positions will be updated, and the groove in the rod (where the fishing line will spool) automatically will move to position itself directly above the holes. Initially, I didn't have exact measurements for the electrode, but since I defined every part as a function of the electrode's dimensions, everything magically updated when I input its exact thickness and width. It's great. It really makes me want to take on a big project, some complex design, and model everything in Inventor. It's also really nice that Autodesk allows free access to their professional-level software for students.

Besides modelling, I spent a good deal of time hunting for a pair of elusive calipers; everybody wanted to use them but nobody knew where they were. We also successfully passed a safety inspection, and I'd spent some time tidying things up beforehand. That's pretty much it.