There are multiple things I needed to balance in the block design for this hotend.

1. Performance: this is pretty self explanitory. I want big meltzone so lots of plastic can be pushed out.
2. Manufacturability (is that a word?): Even though I am not the one who is milling this part, I dont want the JLCCNC worker machining this to have a hard time. Also other people might want to machine it themselves.
3. Cost: Keep the machining simple so cost is low
4. Weight: I had to keep all the parts as light as possible. This is going to be moving at high speeds, so the less weight the better the rigidity will be. Low rigidity leads to crap print quality.

The design is fairly simple. I started with a couple circles to give holes for the heater bore, meltzone, and thermisor to sit. I origonally planned to use an M3 pt1000 thermistor, but was told that a cartridge thermistor would have better thermal control.

I basically just extruded that upwards enough to fit the threaded part of a heatbreak, a supervolcano nozzle adapter (more on that in a sec), and a nozzle. I also added a section at the top for heatbreak stuff.

I added features to allow the pt1000 and heater to fit in, and cleaned up the cad a bit.

Here you can see something close to the final heater block design. I added holes for grubscrews to clamp the heater as well as mounting holes for the heatsink mounts.

About the supervolcano adapter. JLC does not like drilling 2mm holes 51mm long. So instead ill be using an m6 tap all the way through the part to create a 2mm hole. nice! and its cheap too. This also gives me a really nice mating surface for the nozzle so overall really helpful.

Total time spent: 6 hours