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Only had my printer a couple of days and have had good results with PLA so far. I really wanted it to print Nylon, though, so I’ve changed the hot end for the MicroSwiss unit with a hardened steel 0.4mm nozzle. Despite some teething issues I’ve had good PLA results with this new setup but when I try to print anything in Nylon, the temperatures on the bed (85degC) and extruder (typically 260degC) ramp up as specified in the GCode (Cura derived) but as soon as they get up to temperature, the commanded temperatures both drop instantly to zero and they both start cooling down again.

I also sometimes have the file percentage creeping up rapidly (if that’s not an oxymoron) - gets to 100% within a couple of minutes and I know from experience that is a bit quick!

I’ve tried using a lower temperature file that has been shown to successfully print and manually adjusting the temperatures but it still won’t actually start moving the extruder head.

Gcode starts like this:

;FLAVOR:RepRap
;TIME:2469
;Filament used: 2.71499m
;Layer height: 0.2
;Generated with Cura_SteamEngine 3.1.0
T0
M190 S85
M104 S260
M109 S260
M82 ; absolute extrusion mode
G28 ;Home
G1 Z15.0 F6000 ;Move the platform down 15mm
;Prime the extruder
G92 E0
G1 F200 E3
G92 E0
M83 ; relative extrusion mode
;LAYER_COUNT:86
;LAYER:0
M107

I’ve tried swapping round the M190 and M104 commands so that the extruder doesn’t lose temperature so quickly but no joy.

It is very cold at the moment in my workshop but the wife doesn’t want the printer in the house due to the noise! Could the ambient temperature be a factor?

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Sounds like it thinks it has printed. I had a similar problem a long time ago and it turned out to be a bad SD card. My first pass would be to try another SD card, or format the one you have and give it another try. There are a number of values in the source code that limit the temperature, detect the rate at which the temperature is rising, and detect thermistor failure, but I have printed nylon on an i3, with the default code, and not had any issues, but if changing the SD card doesn’t sort it it would be worth sneeking it in to the house :wink: to see if the ambient temperature is having an effect. BTW, I don’t think nylon will take to printing in a cold garage, it is quite fussy about the ambient temperature and drafts.

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Don’t think that’s it - tried it on multiple cards. I’ve now set up OctoPi which should give me some debugging. Did some good printing with carbon PLA but it failed twice and not sure why. Having to sit in a sleeping bag with handwarmers just to let me type commands wasn’t terrifically fun! It really is cold out there and I take your point about Nylon in a cold environment. Plan is to build an insulated enclosure with a heater inside but need to know why the prints are failing in the first place

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I agree, my Nylon prints on my duplicator i3 only work inside an enclosure. Definitely use glue stick too, I had a tough time getting it to stick to PEI.

I’d recommend making something like this: https://www.thingiverse.com/thing:1843235

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Pretty neat looking setup but our nearest Ikea is some way away so I’ll probably just use some 2x2. I have some greenhouse plastic I could use for the sides at least.

What’s best to heat it with? Vivarium warmer?

Just found out after running it through OctoPrint that it’s exceeding MAXTEMP which is a firmware restriction. Don’t know how to change the firmware yet. Had a mare today with a nozzle that kept blocking. Eventually had to change nozzles only to find that the PLA seems to have sucked in a load of water and was fizzing and popping all over the place. Not been a successful day.

Going to try this sometime:

https://silverquark.github.io/i3PlusPlusSite/instructions.html

Gives a maximum temperature of 275 and I don’t intend to use much more than 260. Also looks like it shows a nice graph

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ive had great results on my printer spreading a layer of liquid all white elmers glue, let that dry. Set bed to 100 and then print the part on a raft. You can print directly on the glue and no raft but then the bottom few layers look poor. Then when done and bed around 70ish the glue peels off in one big chunk.

9 Likes
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Right. I’ve upgraded the firmware and managed to print a small Nylon part (cable clip)! My workshop is so cold that it kept giving me a MINTEMP error but warming the bed up to about 20 degrees with a hot air gun solved that. Been plagued with blockages since - second model I tried to print failed but might have been running it too hot. If I can unblock stuff again I’ll try running at a lower temperature…