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So i got my i3v assembled and calibrated and started printing the first small box. During the print I noticed plastic filament coming from between the hotend and the hexagon heat sink. Pulled everything apart and cleaned up the plastic and noticed the heat sink spins freely around the shift that comes from the hotend, but it seems the hotend and the heat sink cannot be seperated. Is the hot end broken??
Colin from Makerfarm says that its normal for some filament to be extruded. Everything is working I suppose.
If the hot end cooling shroud was installed as provided, it could be that what you're seeing is just part of the cooling shroud melting. Some of us now cut away the flat part of the shroud that sits above the aluminum block. IMO, that's almost a necessity when you're printing at higher temps.
Did you retighten the hot end when it was at temperature? That's a good practice to ensure it's tight.
If there is actually a leak, gently clean the mating surfaces of the nozzle and the heat break tube by circling them on a piece of very fine sandpaper laying on a flat surface. That'll remove any small burrs that could be there from manufacturing.
On the spinning heatsink, there's a picture in http://3dprintboard.com/showthread.p...eak-my-hot-end showing what the disassembled hot end looks like. There does just seem to be a long tube that slips into the heatsink.
There was a tip earlier on in the life of the MakerFarm i3 which involved setting the extruder thermistor into its hole with muffler paste. Maybe a smear of muffler paste on the mating surfaces would fill the uneven areas and prevent the leak?
OME
I don't have the fan shroud installed. I cleaned everything and tightened everything while it was hot and there is still a small leak. I'll suppose I'll replace the hotend in a few weeks anyways.
So ive taken the hot end is still leaking from the top threads. Could I wrap the threads with kapton tape to stop this?
I believe the Hexagon has to have a cooling at all times and if you have no fan or a fan without a shroud, it may get too hot. Side effects could include warping of the extruder, carriage and possibly the head itself so that it might not seal. Are you running PLA or ABS temps?
dollarz81, you should definitely be running the fan and the fan shroud at all times, PLA or ABS. I have had my fan stop and all of the above happened that dacb mentioned.
There is a good chance that if you run the fan with the shroud, it will solidify the leaked plastic in the top threads and seal the leak. If you find that this doesn't help, and are planning to get a new hotend anyway, experiment a little and try OME's fix above. Another thing you can try is sealing it with small amount JB Weld. I haven't tried it but it claims to be heat resistant up to 500F so in theory you should be able to print ABS no problem. You might want to get new hotend if/when you wanted to print higher temp materials.
The Hexagon, like other all-metal hot ends tends to loosen when heated, because the aluminum block expands more than the stainless tube. Colin shows in his video how to tighten the hot end, but you really need to tighten it when it's at temperature for it to stay tight.
Just heat it up and tighten it with a couple of wrenches and you should be good.
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.Quote:
Originally Posted by clough42
I'm printing ABS at 250C at around 100mm/s.Quote:
Originally Posted by usarmyaircav
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.
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.
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.Quote:
Originally Posted by dollarz81
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.
I've seen it done (YouTube) with a blowtorch and rubbing alcohol. The video ended with an accidental fire, though...
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.
About 9:17 you see the alcohol reservoir catch fire: http://www.youtube.com/watch?v=6bTfl35zlHE
This was helpful: Dissolving PLA
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.Quote:
Originally Posted by dacb
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.":rolleyes:
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.
For a .4mm nozzle, you'll want a .010"-.014" guitar string. Larger ones won't fit.Quote:
Originally Posted by gmay3
None of the strings this small are wound, so that isn't an issue.
This is one of my favorite 3dprintboard quotes:
I keep thinking that clough42 must be a guitarist who happened to have a spare high E in his case!Quote:
Originally Posted by clough42
I do play guitar, but I had to buy a string for printer maintenance. It's now on a shelf above my hobby bench--right next to the iron.Quote:
Originally Posted by dacb