Another Longsword Derivative

Today I saw that the organ pipe hotend isn't the only descendant of my former Longsword Hotend Project.

Wolfgang (Stoffel15) has built a new all metal hotend which is based on it.

Instead of a fan he uses a self paced water cooling which allows him to keep the hotend very short.

The stainless steel tube runs all along through the cooling bar and is widened up at the top, so it can't slip down. Like in the case of the organ pipe hotend the nozzle and the tube are virtually one part. Unlike with my pipe Wolfgang pressed the tiny brass nozzle into the tube. This is clever, because that way he doesn't need to solder them together. But on the other hand that means to build a very tiny nozzle on the lathe, which is rather difficult.

 As he has widened up the top of his pipe, the only way to pull it out of the cooling bar is upward. That means, if he wants to change the pipe, he must  take the cooling bar out of the extruder block. Not very comfortable yet.

The pipe is fixated to the cooling bar and the heater block by grub screws. I wouldn't have chosen this solution for two reasons.

1. The grub screw presses the tube against the opposite wall thus opening a gap on the side of the screw. A gap blocks the heat transmission from and towards the tube.
2. The grub screw can damage the tube.

The water cooling consists of a wound up brass tube touching the cooling bar. It is difficult to say, how efficient this method is, because a round tube touching a plane doesn't have much contact.

Apart from the fact that this design has room for improvements, I like it a lot. Good job, Wolfgang. ;)

I am pleased to see what open source can do.