broken Hexagon hotend?

[clough42]

clough42, I am just in the 1st steps of putting together my printer, and so have not watched much beyond the build videos, what temp are folks using for ABS, so I know a temp to heat it to that is going to reflect the filiment I will be using.

I'm printing ABS at 250C at around 100mm/s.

[dollarz81]

When I first built the machine, I had the fan and white fan shroud on. I began using black PLA to test the printer when I noticed leak above the aluminum hot end. cleaned up as much as I can and re-assembled while the hot end was heated and it is still leaking. I went ahead and ordered another hexagon from makerfarm. Hopefully this one wont have any issues.

[dacb]

When you receive it, I would definitely do as clough42 suggests and heat and tighten. I don't believe a specific temperature is important just that it gets into the operational range.

[clough42]

When I first built the machine, I had the fan and white fan shroud on. I began using black PLA to test the printer when I noticed leak above the aluminum hot end. cleaned up as much as I can and re-assembled while the hot end was heated and it is still leaking. I went ahead and ordered another hexagon from makerfarm. Hopefully this one wont have any issues.

I have wondered if the melted plastic in the threads might act as a lubricant. In my case, I disassembled everything, soaked it in acetone and cleaned the threads, inside and out before reassembling, heating and tightening. I've since printed about 3Kg of ABS without touching it again.

[dacb]

I would like to know how people clean the PLA out of their hotends. I don't think PLA dissolves in acetone to the same extent as ABS.

[clough42]

I've seen it done (YouTube) with a blowtorch and rubbing alcohol. The video ended with an accidental fire, though...

[printbus]

I took advantage of a hint that I read somewhere - PLA really likes to stick to itself. I heated up metal parts with a hot air gun to melt/soften the PLA and then dabbed them with a piece of filament, with wadded paper towels used to hold down the part. A stick pin was used to clean out accessible threads while the filament was soft. I've never had a truly plugged nozzle, but I have cleaned mine out by finding the right size wire strand removed from stranded wire. Another hint I had read about. Others have used a guitar string.

[dacb]

About 9:17 you see the alcohol reservoir catch fire: http://www.youtube.com/watch?v=6bTfl35zlHE

This was helpful: Dissolving PLA

[printbus]

About 9:17 you see the alcohol reservoir catch fire: http://www.youtube.com/watch?v=6bTfl35zlHE

There's a flash-up at the very end of the video too, after he dropped the nozzle into the alcohol to cool it and the alcohol started boiling. The fumes went upward right into the blow torch. Yikes.

EDIT: "The good news is that I think I've burned off all the residue from the nozzle. The bad news is I can't seem to find it in all the ashes."

[gmay3]

Haha, don't try this at home kids! For the guitar string, I would use the smooth thinner ones that don't have another wire over-wrapping on them. My guess is that this over-wrapping would act like a round file that could change the diameter or shape of your nozzle.