Saturday 27 November 2010

Geared Extruder Hot-End Block finished

My new Aluminium block and resistor heater is finished and is printing very well, here is how I made it -

Drilled holes for the Brass nozzle, two resistors, one thermistor and a locking screw to keep everything tight.
Do this with a long length of Aluminium as it's much easier to clamp and work with, you can cut it down later.

I used two 3.3Ohm Resistors - Wire Wound 3W these will be wired in series- vishay-resistor-ww-3w-5-3r3

Cover them with Aluminium tape (or foil) and insert them into the Aluminium block with a little Heatsink compound if you need it - They should be a tight fit.

Then you can use some Fire Cement to hold them in and seal the ends - Bake at 200 Dec C for 15 mins.



Thermistor fitted into small hole and the resistors connected in series (crimped).

After a few z calibration problems with my last extruder I wanted an easy way to adjust this one, and also a quick to change it over, so this R/A Aluminium mounting plate will give me all that and some extra heat-sinking of the PTFE guide and Extruder.

Slide slots cut, so I can now easily adjust the Z height - really good for testing bed materials that may have different thickness etc.

Now to fit it all to the WADE Geared Extruder - 
All Assembled and wired up.

Done - And the first test cube printed.

Fitted to my Repstrap V1 and after a bit of calibration for the new Extruder feed-rate it's printing extremely well, and giving 100% better prints, and I also now don't need to print a shield as the tiny surface blobs I experienced with the Pinch extruder have all gone.

The Extruded filament is very smooth and consistent, and is producing great results, I'm delighted !

It's printed for about 10 hours now with this new extruder build and still working perfectly, so I can call this a success and move onto upgrading my Repstrap so I can get the print speed up...