Prusa i3 MK2 parts durability to heat  

Re: Prusa i3 MK2 parts durability to heat

For the most part I haven't had any issue with the parts inside my enclosure, but there is what I consider a flaw in the extruder body; there is a stretch of ABS that goes down parallel to the heat block which I have had soften and warp a bit during long ABS prints; it's the piece that the fan shroud screws into, so the fan shroud eventually loosens and starts dragging on the print when this happens.

Unfortunately I haven't come up with a solution to this yet, but otherwise I don't think you'll have any trouble with things unless your enclosure is going to get *really* hot. I don't use extra heating in my enclosure, just what is produced by the bed.

Re: Prusa i3 MK2 parts durability to heat

Thank you for the reply taxilian. I plan on making some larger abs parts. What kind/size exhaust fan do you run for your enclosure if you do use one? And do you have a thermometer inside of your enclosure? If so what temperatures do you try to achieve while doing larger prints? Thanks again for your information.

Re: Prusa i3 MK2 parts durability to heat

Hi Chris,

So the heat issue I've been having it turns out is because I installed the hotend incorrectly =] it shouldn't have been as close to the plastic as it was.

Otherwise you'll have trouble with the stepper motors before you're likely to have trouble with the printed parts. I usually have my enclosure running at around 60C but that's just what the ambient temp reaches (I have a thermometer in the enclosure) from the bed. I have no exhaust fan in my enclosure at present. The hottest I've run is doing PC-ABS with the bed at 130C and the nozzle at 285C (which is running right now, actually)

Re: Prusa i3 MK2 parts durability to heat

This is great information. I figured on mounting a fan on mine for the sake of printing other materials but having a removable blockoff plate to install during abs prints. I also thought about installing a bbq grill style vent to allow me to somewhat control how much heat can leave during abs prints. Please let me know how that current print comes out at 130 C. That is hotter than I thought the printer could handle. What have you built you enclosure out of? If you have the ability to post a pick I would love to see it. Thanks again!

Re: Prusa i3 MK2 parts durability to heat

This is my third print at that temperature and the last two both worked fine. The current looks good, though I do have 8 separate parts on the bed right now, so that changes things a bit. I also have replaced my PEI with PrintBite which is partly why I have the temp so high -- printbite likes higher temp on the bed. I did make a small mod to my mk2 and opened the power supply and adjusted the voltage all the way up (about 13.9V) which gives the heated bed a bit more power. (well, actually about 80% more power), so it's possible that you may not be able to hit 130 without that. Note that if you do that you'll need to do PID tuning on both the bed and hotend.

Richard