While I have built two or three J-Head Mk V concept models, shown above is the first prototype. For the sake of comparision, above the prototype is a J-Head Mk IV-B. While it needs to be tested, I believe that there is a pretty good chance it will meet the 3 most important primary goals.
The Mk V goals were:
- Shorter overall length (Met.)
- Lower extrusion pressure and faster speed (May be met, needs testing.)
- The melt chamber is more than double the size of the melt chamber in the Mk IV-B.
- The orifice length will be kept to around 0.030".
- A special drill bit has been ground that creates a steeper taper at the nozzle orifice. This change is similar to other hot-ends that are available as a 118 degree drill bit is not ideal for a hot-end.
- Designed for the 6.8 ohm resistor (Was not met.)
- I was able to fit the 5.6 ohm resistor in the Mk V prototype. However, if the 5.6 ohm resistor becomes unavailable, I will re-visit this decision.
- Nozzle may use 1/2" x 1/2" brass stock (Met.)
- Different thermistor mounting location (Was not met.)
- I decided to keep the thermistor mounting location the same, for now.
Since the nozzle has been machined out of 13mm x 13mm square brass stock, an aluminum nozzle is now feasible. I will probably keep the same naming convention. Therefore, the J-Head Mk V will be aluminum and the J-Head Mk V-B will be brass.