Sunday, December 11, 2011

Extrusion success!!1! well, almost

I finally got some PLA to appear from the nozzle of my long awaited Sumpod.  It´s not much to look at but it proves that I can get plastic out of that thing.  But there are a few caveats still apart from the underwhelming amount extruded :)

I could not get the tip above 190°C with out shutting down the fan.  I did so for just a moment to get to 196°C.  I did not want to run it for much longer fearing that I will clog the whole this as other Sumpodders have experienced when running with the fan on.  It seem like I need a few degrees more with the PLA filament I have to get this working properly.  Another thing was that I fed the filament my hand through the teflon tube.

There are a few tricks I can try when I give it a go next time as it's to late right now for me to bother with any bravery.

1. Add more insulation
This will currently entail adding a bunch more kapton tape to the hot end.  I have 6mm roll I use for job. That should give me a bit more head room.
The long term plant is to use some fancy NASA tech in the form of an aerogel based insulation blanket called Pyrogel.  Which incidentally arrived on Friday.  That is a very dusty material with very fine particles aside from being quite expensive so I won't be doing that in a rush.  It will also be quite permanent after I seal as I'd rather not have dust spreading.

2. Regulate the fan
The extruder fan is running non stop on 12V and if I run it down a notch to decrease the amount of heat it's dissipating from the hot end.  I have a few options here and the simplest being to add a pot temporarily while I test the effect.  More fancy solution would be to add PWM to the firmware but I'd like to avoid that if possible.

That it for now