Hemera Upgrade 3.0  

RE: Hemera Upgrade 3.0

Thanks for continuing to work on this!

After weeks of refreshing store pages to find one in stock, I was finally able to secure a Hemera order today and should have it in 3 weeks. I plan on going with your implementation.

RE: Hemera Upgrade 3.0

Hey,
thanks for the upgrade. With this upgrade I will give the hemera a try. But could you please tell me, which parts in the firmware I need to modify? I want to compile the firmware for myself.

Thanks

RE: Hemera Upgrade 3.0

@sternmiere

Hi,

Details about FW changes are now in the print description.

sorry for letting you wait.

RE: Hemera Upgrade 3.0

I am using this and if you have a donate button somewhere I would use it.

I would like to add some tips for people that might attempt this mod in the future (seems anachronistic to use a v6 and OG hemera in >=2023 but who knows)

• Use the old hotend fan that came with your MK3 for the hemera. The fan that comes with the hemera is a different voltage and connector.
• Pinda probe cable routing is unintuitive, see pics below
• The stepper motor cable the Hemera comes with appears to have the blue and red wires reversed compared to the prusa stepper motor cables, however I left it alone and it spun in the correct direction
• If the hex nut that marries the two halves of the upgrade parts keeps falling out of its hole, try a tiny bit of masking tape to take up the extra space, or use an extra long M3 screw to pull it into position so that the m3x18 can engage it.
• I used these cables for the thermistor and and heater cartridge (if the heater cartridge has a connector, like this one )

Printed in MJF nylon from JLCPCB

This design is elegant and simple. I chose this design over the alternatives because it does not over-complicate things and gets the job done. There was serious attention to detail in the modeling as well. I think overall this is a exceptionally good design. I think this is the only design I have ever downloaded from thingiverse that *just works*.

If I had to provide some constructive criticism, I would say the worst part of this design is the nut that holds the two haves of the extruder together is hexagonal, and the hole was too oversized (for my print).

This meant that the hex nut kept moving out of position, which was infuriating while trying to hold everything else in place during the two-sides-mating-ballet. Much more critically, using a hex nut instead of a quad nut (4 sided square nut) means that the nut is much easier to overtorque, spinning and deforming the plastic hole that holds it ( this was easy to do in MJF nylon, so I can assume it would be worse in FDM PETG).

The second flaw I find with this design is the suggested cable routing path (between the two parts which slide together) is inviting cable pinching. When you slide the two halves together, it is very easy for some of the loose wires to get ground between the two haves, and you can't see whats going on or check if the wires are intact.

But again, this is a fantastic print overall.