CoreOne Obxidian Nozzle size/length Mismatch
Search doesn't show anyone asking this... so:
New CoreOne, new Obxidian nozzle for it.
When installing the new nozzle, I find the new nozzle has quite a bit different over dimensions than the stock nozzle: primary concern is where the heat break ends up in the stack. This is caused by the hex portion being a few mm taller than the brass nozzle, reducing the back side length of the filament guide and location of heat break.
With all of the issues the heat break positioning has caused on Mk3 printers, I am reluctant to install the new nozzle: Any thoughts?
Here's an image of the issue:
RE: CoreOne Obxidian Nozzle size/length Mismatch
Hello,
I have used the 0.4 Obsidian nozzle (HF version) on my Core One for many hundreds of hours now with no issue. Note that the difference in nozzle dimension from the heat block only results in the heat block resting higher in the Nextruder assembly. The relationship between the top of the heat break tube and the positioning features (grooves, top of copper band) are unchanged so cooling of the heatbreak is essentially unchanged. Note that nozzzle changing tools have been produced by several (look on Printables) that compensate for the higher positioning of the heat block in order to properly secure the block for a nozzle change in situ.
Regards,
Steve
RE: CoreOne Obxidian Nozzle size/length Mismatch
More store research, and apparently the CoreOne does NOT come with a high flow nozzle, despite all the literature saying it does; the brass high flow has a longer hex area, just like the Obx HF shown in the images.
RE: CoreOne Obxidian Nozzle size/length Mismatch
The high flow nozzle will have CHT stamped on the tube. I received the 0.4mm CHT (high flow nozzle) with my kit.
More store research, and apparently the CoreOne does NOT come with a high flow nozzle, despite all the literature saying it does; the brass high flow has a longer hex area, just like the Obx HF shown in the images.
RE: CoreOne Obxidian Nozzle size/length Mismatch
Sorry hyiger, the CHT is not the high flow nozzle. See the image above that shows what the actual high flow looks like (with 7mm tall HEX). You can also check the store for the variations. While the CHT means a nozzle might print faster than a non-CHT, it is not quite a high flow nozzle (higher volumetric flow rates). Consider that if a CHT is high flow, why does Prusa sell a high flow brass nozzle in addition to the brass, and brass CHT versions?
Here's what CHT means:
In Prusa 3D printing nozzles, CHT stands for Core Heating Technology. This is a Bondtech-patented internal nozzle geometry that splits the filament into multiple channels, increasing the surface area for heat transfer and allowing for higher melt rates, which results in a faster printing speed.
RE: CoreOne Obxidian Nozzle size/length Mismatch
Beware, there are two versions of the high flow brass nozzles on offer. The one you pictured is the E3D version E3D prusa high flow nozzle. The other, as alluded to by Hyiger, is the Prusa Nozzle Brass - CHT. The two nozzles are functionally identical but use slightly different (as I understand it) means to accomplish the multiple filament passages within the nozzle head. I believe that the E3D version is based upon Bondtech's design and the result is a slightly longer "hex" portion on the nozzle as found on the Nextruder Obsidian nozzles.
The 0.4mm nozzle provided with the Core One is the CHT version and can be identified, as Hyiger stated, by the markings on the heat break tube of the nozzle.
Regards,
Steve
RE: CoreOne Obxidian Nozzle size/length Mismatch
Sorry hyiger, the CHT is not the high flow nozzle. See the image above that shows what the actual high flow looks like (with 7mm tall HEX). You can also check the store for the variations. While the CHT means a nozzle might print faster than a non-CHT, it is not quite a high flow nozzle (higher volumetric flow rates). Consider that if a CHT is high flow, why does Prusa sell a high flow brass nozzle in addition to the brass, and brass CHT versions?
Here's what CHT means:
In Prusa 3D printing nozzles, CHT stands for Core Heating Technology. This is a Bondtech-patented internal nozzle geometry that splits the filament into multiple channels, increasing the surface area for heat transfer and allowing for higher melt rates, which results in a faster printing speed.
To be completely clear, Prusa disagrees with your statement above. This is a direct quote from their blog post announcing the MK4S printer:
"Furthermore, the MK4S now comes standard with a high-flow nozzle of our own design based on the CHT technology."
As I indicated in my post earlier there are two different "high flow" nozzle designs for the Nextruder printers. Prusa's own is the CHT nozzle and this is the one delivered with MK4S and Core One printers.
Hopefully this helps clear up the confusion.
Regards,
Steve
RE:
Sorry hyiger, the CHT is not the high flow nozzle. See the image above that shows what the actual high flow looks like (with 7mm tall HEX). You can also check the store for the variations. While the CHT means a nozzle might print faster than a non-CHT, it is not quite a high flow nozzle (higher volumetric flow rates). Consider that if a CHT is high flow, why does Prusa sell a high flow brass nozzle in addition to the brass, and brass CHT versions?
Correct, the CHT is not the high flow nozzle, it's a high flow nozzle. Prusa reference the CHT as a high flow nozzle and it requires a HF nozzle setting in the slicer. As stated on their product page:
This all-metal high-precision high-flow nozzle with a CHT (Core Heating Technology) for the Nextruder combines both nozzle and heatbreak.
RE:
All said, I won't argue the point, rather, I ask where is the data that shows the maximal flow rates for each nozzle? Once I see that information the terms should become clear. Does anyone watching this thread know of such a comparison/benchmark?
I purchased the hardened HF nozzle (the E3D version) because the Core is supposed to do faster extrusion than the Mk3. I really didn't expect a physical assembly difference, so that was a surprise. The printer is back together now and printing, and honestly I haven't a clue if printing qualities have changed - just no experience with the 'before' condition ... one test print, lol.
My Mk3 was maxed out at 12.5mm/s -- I wonder is anyone has done a similar measurement with these various nozzles. If only the forum search function were more user friendly: searching for "nozzle comparison" in the English Core One forums has no results. Extending the search to all Core One and Mk4s topics ... a page of results dealing with nozzle printing issues. Sigh.
ps: first google search dropped this:
RE: CoreOne Obxidian Nozzle size/length Mismatch
Also found E3D has data available, some links broken but with perseverance I found some nozzle info. Nothing spectacular regarding PLA with comparing the 0.4 E3D brass to E3D HF brass and E3D HF Obxidian -- the HF models have ~20% higher flow rates with PLA at 220c. (16mm/s vs 20mm/s). PETG and ASA have higher gains.