Friday, May 11, 2012

J-Head Hot-Ends Shipped Out For Field Testing

The first 3 Mk V-B hot-ends were shipped out, today, for field testing.  I added the extra vent and the mounting groove, to them, and I am considering CNC'ing the mounting grooves in the future.  The mounting groove, shown here, was made on a 4 axis milling machine as opposed to a form tool on the turret lathe.  I will have to compare both the time required to make such a groove and clean it up, using the CNC mill, or the time required for setup and other issues, on the turret lathe.  Another factor is that the Mk VI J-Head will required a CNC'd mounting system as I am planning on improving that at some point in the future.

In addition, I shipped out two "Mini" J-head hot-ends, for testing.  The Mk II Mini J-Head looks identical to the MK V.  However, internally, it is designed specifically for 1.75mm filament and I will be updating the Wiki Page and adding more information about it in the near future.

Unlike the Mk IV-B 1.75mm hot-end, the Mk II Mini J-Head is not a conversion.  It has quietly been in development for several months at this time.  The Mk II Mini J-Head was already very similar to the Mk V and I decided to make it identical, externally, in order to reduce the inventory required to produce either hot-end.  In many respects, the Mk V (3mm) hot-end is basically a Mini J-Head adapted for 3mm filament.

Internally, the Mini J-Head uses a PTFE liner that has an OD of 4mm and an ID of 2mm.  The means that there will no longer be a custom machined liner used to convert a standard hot-end to 1.75mm filament.  The brass nozzle is also different, internally, in order to accomodate the smaller filament size.  Some of the testing, and lessons learned, from the Mini J-Head were used in the development of the Mk V version of the standard J-Head hot-end.


  1. Looks Great, can't wait for feedback on the Mini J-head ends, I'm desperate for a really good 1.75mm hot-end.
    Keep us updated.


  2. TCZ:

    Thus far, both the J-Head Mk V-B and Mini J-Head have printed PLA without any serious issues. A J-Head Mk V-B was also sent out, with a 0.25mm, nozzle and has printed fine. ABS hasn't been tried, yet.