**These nozzles are discounted for clearance** They are the original Prometheus Hot End nozzles and they work great with both the V1.1 and V2 hot ends.
- 1x Prometheus V1.1 Nozzle
[NOTE** Also compatible with Prometheus V2]
The 1-Piece Stainless Steel Nozzle is precision CNC-machined and polished for a beautiful surface finish. Stainless Steel was chosen as the material for the 1-piece nozzle due to its low thermal conductivity, low thermal expansion, and high strength. This design replaces the standard nozzle and heat break combination in most all-metal hot end designs with a 1-piece nozzle that eliminates all internal "melt-zone" junctions.
Internal "melt-zone" junctions are the leading cause of leaks and clogs in conventional hot end designs. Molten plastic can leak through the junction or can get stuck in the junction, decompose, and the charred remains can then flow down and clog the nozzle orifice. I have experienced these problems even with the best hot end designs. With my 1-piece nozzle/heat-break design I have completely eliminated all internal “melt-zone” junctions and thus eliminated the possibility of "melt-zone" related leaking or clogging. With several hundred hours of printing and not a single leak or clog, the empirical results speak for themselves.
In addition to the 1-piece design I was meticulous about Electropolishing the internal pathway of the nozzle to avoid the possibility of the filament jamming. Filament jamming is the most significant problem associated with all-metal hot ends. While hot end “clogging” relates to the obstruction of the nozzle orifice, hot end “jamming” is associated with the forces involved in filament extrusion. In order to extrude filament successfully the applied force of the extruder drive must be greater than the opposing force of friction.
Friction occurs most prominently in the “transition-zone” of the hot end where the plastic is changing from solid, to rubbery, to liquid. The plastic remains solid in the "cold-zone" until it is heated above its Glass Transition Temperature (Tg) in the "transition-zone" at which point it is "rubbery" until it is heated above its Melting Temperature (Tm) and turns to liquid in the "melt-zone". In its “rubbery” state at temperatures between Tg and Tm, the plastic turns soft and expands to form a plug in the “transition-zone”. This plug of soft rubbery plastic is the most significant source of friction in the hot end and is the leading cause of hot end jams.The standard J-Head hot end design features a low friction PTFE liner that extends the full length of the “transition-zone” and greatly reduces the friction caused by this plug. However, all-metal hot ends do not have a PTFE lined “transition-zone” so friction becomes a significant issue especially when printing PLA. To overcome this problem I Electropolished the full length of the internal bore of the nozzle. The Electropolishing procedure is one of the most advanced Stainless Steel polishing procedures available. Electropolishing the internal pathway of the nozzle to a near mirror finish ensures that it is smooth enough to eliminate jamming.