This 3D printer for kids can help them invent and build their own toys

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No enclosure? Hot parts, plastic fumes, moving machinery and kids do not go together!

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I’d say it’s quite safe. As for hot parts, the only exposed part is an extruder tip, which is quite small and not very hot (about 180-210 deg. C). Minor burns to fingers are the very worst thing that can happen. If good quality PLA filament is used, fumes from melted plastic are not a problem (but the printer still should be used in a well ventilated area). ABS filament is obviously no-go. Moving parts are also perfectly safe. The printer uses belt-driven design for horizontal axes, so at this scale it’s more delicate than most RC toys.

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Don’t even PLA printers give off nano-particle sized emissions?

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I’m so ready to buy my kid (and myself) a 3D printer, but I’m waiting for him to get a bit older so he can make his own designs. Until then, a 3D printer is just a plastic crap machine.

I’m also hoping that by the time I’m ready to buy, there’s an easy way to recycle filament at home. I envision a future where my son has 2kg of toys at any given time. Want to make something new? Gotta throw something old in the recycler…

Aside; I need help with a couple of 3D printing designs I have a vision for. Anyone here can help?


Thanks, I didn’t know that. It seems though that nanoparticles from high quality PLA are completely harmless (it makes sense, because there are surgical implants made from medical grade PLA that slowly decompose into lactic acid).
From the article:

While PLA-generated UFPs have actually been shown to be biocompatible with mammals, previous studies have demonstrated that thermal decomposition byproducts from ABS processing have toxic effects in mice and rats.

Desktop machines that extrude plastic granulate into filament are already available and allow not only recycling of failed prints, but also plastic trash of known composition. You just have to grind the plastic into granulate first. Complete machines cost about 600$, but there are DIY solutions that are cheaper than that.

If you’ll have any problems with modeling in open source software, PM me - I’ll be happy to help :slight_smile:

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You mean the grinders are $600, or an all-in-one solution? I did some googling around before I posted and saw some interesting hobbyist options but those seemed to take quite a bit of work and yielded inconsistent results. I really want something that looks like a Mr. Fusion that you could just feed plastic toys into and get nice rolls of filament out :smiley: It’d be so cool if there were local options for that, like a PLA recycling center at the corner Radio Shack. But of course, that can’t happen now. Maker Media really should have bought Radio Shack.

I’m just getting back into 3D modeling. I did a bit like 5-6 years ago and was using Google’s SketchUp, but I guess it’s not free anymore. I looked for good alternatives but didn’t really know which one to use. I played with TinkerCAD this weekend and it was actually super easy, but there are some missing features (or at least, I’m missing them). What open source software would you recommend?

My projects are an Airpods case that I’m hoping is simple enough to make myself, and a reproduction of the Information Services mask from Brazil that I want for Halloween. No way in hell I think I’ll be able to pull that off myself.


600$ is the cost of the extruder - machine making filament from ground up plastic:

900$ can get you the larger version:

As for shredder/granulator, you can get used industrial machine for about 250$. It is a really simple machine (motor, two spinning blades, two static blades and a sieve), so probably you can DIY something even cheaper and make it smaller.
Here’s typical industrial granulator used to recycle waste plastic from injection molding machines (I’m sorry that the site is not in English, but it shows what’s inside machine):

For projects with simple parts and complicated moving assemblies I use SolveSpace. It’s amazing parametric modeler with really good assembly constraints. It’s also fun to use.
For complex technical parts FreeCAD is fine. It’s still far from being finished, but it’s based on extremely powerful OpenCASCADE constructive solid geometry kernel. Be sure to build it from source and enable ASSEMBLY2 module. Binary versions are outdated (same with the SolveSpace).
For extremely complex models I recommend Blender 2.8 (interface changed recently and it’s far more friendly to beginners than it was with 2.79). I use it for stuff like furniture, various motorcycle parts with complex surfaces, especially those that have to mate with other parts that I’ve 3d scanned. Blender has a good extension for analyzing models before printing (visualizing wall thickness, etc.), and nice extension for computer aided manufacturing.

For the mask I recommend using Sculpt mode in Blender 2.8. Be sure to turn on dynamic topology and symmetry. It’s far more intuitive than typical subdivision based modeling (“Edit mode” with Subdivision modifier ). When you finish modeling the surface, use “Solidify” modifier to add thickness to it. Sculpt mode in Blender works very well with Wacom pen tablets.


Cool - thanks for all that info! I’ll try out Blender at least for the mask. Interface is important because I really don’t have time to be teaching myself more of these programs for all the side-projects I have.

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If you will have any questions about it, feel free to ask :slight_smile:

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If there is no chance for third degree burns or electrocution, it’s not gonna be fun…

If the world was a just place, I would have no fingerprints left.


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