Saturday, August 23, 2008

Extruder Lashup

Originally uploaded by thebluedirt
This extruder is designed for higher-temperature operation than the RepRap design. It uses a 1/4" dia, 2" long cartridge heater for heat.

The holding block has a hole for the catridget heater, and holds the barrel via a clamping arrangement with the bolts at the top.

I wanted to operate at temperatures above what PTFE could handle, so I used a three-part extruder barrel:

The lower barel is brass, threaded on both ends to accept the acorn nozzle and the adapter.

The adapter is aluminum, with fins cut into it to maximize cooling

The entry end is stainless steel, and threads into the adapter.

The result is that the heat gradient over the entire barrel is enough to keep the entry point cool, while the brass part melts the plastic.


Mr Rick said...

Greenville, SC? We could be neighbors! I was also considering using Al in lieu of Teflon for the holder. My design appears similar to yours, did you mill it yourself or get somebody local?


Dave said...


I made the parts myself-- I have a small mill and a lathe.

I have had a good results so far, i have taken a break for the holidays, but i'm close to mounting the parts into a piece of Alum. channel, thus promoting it from a "lashup" to a "prototype" :)

I live on the east side of gville off pelham road. That in your parts? If so, shoot me an email...

Mr Rick said...


Sent you a PM over in the RepRap forums. Wouldn't recommend posting an email for the world to see. ;)