Here we try to answer the more general questions. Answers are arranged by category.
Printers
There are a ton of options, your budget and goals will determine which you buy. I use the Prusa i3 MK3, a great machine, though a bit out dated by todays standards. The Ender 3 line of printers from Creality is extremely popular for a reason, because they are low cost and can work quite well. Though be warned, some tinkering will be required. There are many Ender clones on the market that are a bit better or worse, watch a few reviews before buying. A printer like the Bambu Lab X1 would be a great option for out of the box printing, though you will pay more.
We use Prusa i3 MK3 printers for most parts. I also use an Ender 3.
I use the E3D NozzleX. Brass Nozzles will work great with non abrasive filaments, but I highly recommend a hardened nozzle if you are going to print any filled materials. Stay away from low quality off brands if you can, a bad nozzle will insure a bad print.
0.4 MM is the standard that most models are designed for. 0.6 MM will also work in many cases, but check the documentation to see if it’s compatible. 0.25 MM nozzle are great for fine detail on some parts, but are not needed unless specifically specified.
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