A clearly-labeled plastic box smaller than the actual metal meter is not likely to cause this law to be invoked, since there is no way in hell that a reasonable person could mistake it for the real thing. It would be like mistaking a Tonka toy for actual construction equipment.

This model on Thingiverse looks like it might be fairly close.

I actually own a D-cell-capable charger (also takes other sizes down to AAA). I guarantee you that it cost a lot more than this—$50 Canadian before the pandemic. So I can understand the attraction of hacking one of the cheaper chargers.

Microsoft has prepackaged VMs that you can use for a short duration without (in my experience) triggering an update cycle. Of course, they’re Windows 11 and need VirtualBox, which may not be ideal.

The auto-bed leveling on your 3D printer is nice, but it’s not a replacement for manually leveling the bed. Manually level the bed before every print, since taking off your last print from the bed has the tendency to make your bed not level. Then, after manual leveling, do an auto-bed leveling to remove the remaining tiny variations in the bed level

Depends on your printer, I think. Mine is quite happy being leveled only after nozzle changes, and the autolevel is Good Enough.

There are a few directions you could go in to have the print flex: print from flexible material (although I’m not sure that even the softest grade of Ninjaflex would be flexible enough), or, as someone has already suggested, create a mold for silicone casting. Or, in the worst case, modify one of those sectioned print-in-place flexible snake models, although the result won’t be as realistic.

I was hesitating to suggest this, but do you think you could usefully modify a realistic dildo model? Cults3D probably has a few—I think they’re the only major repository with a sex toy section.

Urological models don’t seem to be common (you can get bones, hearts, and a few other organs from the US NIH, though). However, one of the things I did turn up in a quick web search was several mentions of software that can be used to turn medical imaging data (MRI, possibly others) into models for printing. It’s usually used for setting up individualized treatment plans. Maybe what you need is a former patient who’s had the appropriate regions scanned and might be willing to release the data to you for such a purpose.

My cats don’t even pay attention. Maybe it’s the enclosure.

Just a minor note: if you do proceed with this, consider carefully the orientation you print in. The Z-direction in FDM 3D prints is almost always the weakest, so you may get better durability by printing these lying on their sides. Worth testing, at least. (Also, everything everyone else said.)

Well, not anything (if you actually think that’s possible, then I have a challenge for you: make a functioning gun out of cheese), but an average hardware store should have everything you need to produce something capable of firing a shot.

I admit you’d be limiting your market to people who consider “helping the environment feels good” to be worth at least $5 if you price the spools at $20 USD. If you want to price it lower, you need more waste, though. So for now, the economics don’t really work out unless we’re talking about really large groups of hobbyist printers, or waste from a business. 🤷

Alternatively, what’s impossible for an individual might be possible for a group. A makerspace with enough members who are into 3D printing might be able to break even on a macerator, extruder, and spooler in a reasonable amount of time by reselling the filament. Say maybe 30 people each producing a kg of waste PLA per year?

Hmm. Pinning some numbers on this . . . The Filabot EX2 is an extrusion and spooling setup for $6,560.70 USD . Plus the bill of parts for a DIY macerator . . . let’s call it $7000, because round numbers are nice. $1000 a year would pay this off in a not-unreasonable amount of time. So you’d need to produce 100 spools at $10 or 50 spools at $20. If you’re only clearing 30kg of waste per year, and selling 1kg spools at $20, that’s $600/year and about 12 years to pay off the rig. Still not completely out of the question, I guess.

I think in most cases you have to pay the price of postage. Some of the companies will offer you an incentive like free or discounted spools of recycled filament to offset this, but the only one I’ve found that’s in Canada with me ( filaments.ca ) does not. Printerior Designs in the US apparently does (never dealt with them myself), and there are a couple in the EU.

When I looked into this a couple of years back, the prices for ready-made filament extrusion setups looked like the target market was small business rather than individuals. And the recommended DIY method for breaking down plastic if you didn’t have a machine shop was to get a paper shredder with metal blades (one of the models capable of shredding optical disks).

Much simpler to recycle printer waste into slab material. Or send it to a manufacturer that does recycling. Unless you’re generating at least tens of kilos of waste a year, you’re unlikely to break even any time soon by re-extruding, assuming the resulting filament is usable at all (ensuring consistent diameter and near-perfectly round cross-section is probably a PITA).

In addition to the stuff other people have pointed out, make sure you glue your insulation down very well, so that it won’t fall off and come into contact with your print head. Just in case. Other than that, I don’t see anything other than the usual potential electrical issues.

If you poke around long enough, you can find sample packs of 200g-500g spools, for instance this set of 9 colours from a Canadian company (they offer most of it in individual 1kg spools as well, with Pantone colour references for matching, so if you really need to reorder you can).

Forth. Gotta love that RPN . . .

Software is like clutter in your closet: it expands to fill the space available. There doesn’t seem any way to prevent it. I’m starting to think the whole phenomenon is related to the Second Law of Thermodynamics. 🤨

The choice of stack would matter a lot less if the documentation were better. Last I checked, having to figure out the details of message semantics from scratch made writing better frontends or alternative server implementations in other languages ten times more difficult than it needs to be.

Spool3D has a fair assortment of printer parts, although I don’t know if they have exactly what you need. They’re in Calgary. I’ve ordered from them once, although it was just filament samples, and got everything in a reasonable amount of time.