Anodized aluminium hotend

I though I post something about my new design: An anodised aluminium heater with build in heating wire.
The design is pretty simple and straight forward, take a piece of aluminium round bar, add a thread for the wire and some holes for filament, nozzle and heat barrier.
Here is the machined and anodised core:

Due to being too blonde to drill holes smaller than 0.5mm I decided to change the design slightly to allow for standard brass nozzles to be screwed in.
Add some heating wire and give it a good coat with silicone heat plaster:

Of course the thread was covered fully...

Basic design before adding the wiring loom compared to a standard J-head:


Mount, heat barrier and nozzle:


Extrusion test of the new nozzle:
Extrusion test
Print test at 40mm/s:
Print test at 40mm/s
Print test a bit further down the print:
Further down the print
And at 80mm/s only slowed by the acceleration control:
At 80mm/s

I was trying to create a slimline and very fast heating hotend and I think I accomplished this.
Using anodised aluminium for the heater core allows to create the same heating as conventional desgins but with a much smaller footprint in diameter.
Using a shorter neck on the heater block and a properly machined heat barrier will reduce the lenght but I have to wait for the PEEK to arrive as the teflon is a bit too flexible for my liking.
If you want to read the whole story on how this hotend evolved check my Instructable as I will update there a bit more often.

Edited 1 time(s). Last edit at 06/13/2015 01:25PM by Downunder35m.

Really interresting, thank you for sharing !
Unfortunattely I don't have the tool to try it ...but it is impressive

I am currently working on a model that is close to the E3D design but uses the direct heating system.
First batch of aluminium deliverd was the wrong type as I could not anodize it at all, waiting for the replacement now.
Initial tests showed the above design is almost perfect for PLA prints, ABS too if you stay below the critical temp for the teflon liner.
Polishing stainless steel is a real pain and so far I ordered 3 heat barriers in "highly polished" that still had the drill marks in them.
So my though is to make use of the abresion resistance of the aluminium oxide so ne liner is required.
Only problem so far is to get the area between hot and cold end right.
0.1mm to big for the hole and the plastic fills up the cold end, 0.1mm under the desired size and the filament can get stuck.
Will report back on the new version in about two weeks, time permitting, and upload some pics as well.