Talk:Glass Nozzles
I don't get this. If glass is an insulator then how can the heat get from the nichrome on the outside to the filament in the middle?
Have you tried actually pushing filament through by hand yet? Does it work? --GilesBathgate 16:02, 25 September 2010 (UTC)
Giles, I think what is happening is that the heat passes from the outside of the nozzle to the inside, but does not (noticeably) travel up to the rest of the extruder. (The glass is a non-perfect insulator; hot water in a glass teapot will make the outside hot, but the handle may not feel noticeably warm, whereas a brass teapot would have a hot handle.) --Sebastien Bailard 04:35, 26 September 2010 (UTC)
I have confirmed that this Glass Nozzle (supplied by Rocket_Scientist) is a near perfect extruder hot end. I have personally smashed this into my Z axis over a dozen times, dragged it through an uneven board; currently have it wedged into a wooden block to the point I can't extract it; and spent a lot of time with uneven heating and such. It has taken all the abuse without any marks. The only downside is that PLA likes to stick to glass and my cheap Blue Tape refuses PLA like it was made out of teflon. The glass then gets some PLA on it, but it is easy to remove. The hot end worked perfect right from the first get go and no matter how high I set the temp it will not damage my extruder or carriage because of the wood block heatsink I added but didn't need. Though I doubt the glass even gets the hot more then an inch up beyond the nichrome wire due to its properties.
Secondly, the PLA does not stick to the inside of the glass to the point of becoming a problem. It passes through cleanly and if you need to remove the entire unpushed through portion: Do not cut your PLA filament, I remove the cold end from the wooden block and snip it about 3 inches up. Then it pulls clean with a little 'pop' and I have a perfect Nintendo 3DS super accurate pen as a result. You can then insert another color filament or type without having to extrude the rest out.
Might update this page with Rocket_Scientist's permission to reflect my findings.Loxia 06:04, 14 December 2011 (UTC)
