Printing in hot weather.

Anyone else have this problem of no airconditioning, and seemingly too high a room temperature to print?
(from sydney australia)
The first time i tried printing on a really hot day, (usually i print at night when i get home from work around midnight) my hot zone moved too far up and my extruder jammed. I blame it on the heat because this setup had printed a few large parts during the night and hadn't given me any problems.

I then put a computer fan aimed at the ptfe and this seemed to solve it for about 6 or so medium sized parts, but now we are having some over 40 degree days and it seems the fan isn't working anymore because i guess it's just blowing hot air and my extruder started to stall again. The other night it was 35 degrees at 2am which i'm not sure if i can print in, even at night the temp hasn't been dropping below 30 for the past few days.

But then i hear about temp controlled cases around printers that are set to something like 45 degrees? Which makes me think the heat should be helping?

I was thinking of making some kind of ice holder to go behind the fan, with a drainage system to take the water away as it melts. And i just have to be there to top up the ice. But i thought i'de put it to you people.

actually one thing i haven't tried is dropping my printing temp from 250 to say 240...

I think one of the problems with a heated chamber is the extruder motor overheating. I've not heard of the extruder itself having problems, but it makes sense that it would.

It should be possible to compensate with a thicker insulator though, a longer piece of PTFE or something.

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I'm building it with Baling Wire

I should mention that i'm using adrians latest ptfe going into brass + peek design, so far in cool weather it has treated me very well almost got a full mendel except for the x carriage and upper, which i need to extend my stage for.

surprisingly the weather dropped, but the extruder was still already at 30 degrees, i tried and after about 15 layers of the XLR bracket it stalled, so i quickly undid the springs and pulled the filament right out of the extruder and by the look of it it is is expanding up at the ptfe.

i think tomorrow i'm going to cool the outside walls with the hose, no water restrictions at the moment. it feels cool outside now but even with windows open, the roller door and the door open it's hard to cool room temp down because there is just no breeze at all.. just giant spiders everywhere indoors and out that think you walking past is the breeze and drop on you and baby spiders making there first webs in between the wires of my printer

actually maybe i could hit the whole printer with a giant fan? but still i guess it's only blowing hot air.

here i am complaining it's too hot to print when up north on the same coast people still dealing with flooding are dealing with this:

Have you considered a large box fan with a few bags of ice hanging off of the front of the fan?
It's not pretty or efficient, but it will lower the air temp a few degrees

Blowing on the whole printer may cause shrinkage and layer adhesion problems as the part you are printing cools - especially for larger parts. You might want to consider using heat-resistant shields or duct work of some kind to guide the airflow over the extruder cold end rather than blowing on the whole printer. Of course, this could be a suitable test of whether or not the concept will help before you invest a bunch of time into making miniature duct work.

about the only 2 things i can think of are, 1 get ac, or 2 wait until it is cooler to print again. the only thing i can think of other than that would to be more space between your hot end and your cool end.

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[mike-mack.blogspot.com]

well i have taken a leaf out of nopheads book and put some brass tubing around the PTFE making it a very tight fit. I will try printing when the weather drops below 30 hopefully tonight.

i meant to say 'and i made it a tight fit'

k that didn't solve it although seemed to help. edit: extruder was already 31 deg, with brass around ptfe the filament didn't really plug up till it was completely blocked, but teeth eventually started clogging up.

i think i might make an all steel extruder, longer than normal with lots of heat dissipation up top and fan.

i also might make an evaporative cooler for my mendels ventilation chamber.

was supposed to be cool today, yet the printer was 41 degrees when i got home at 5. 10pm and my printer is 35 degrees. annoying! (not being able to print)

this reminds me of a story of a friend who came back from traveling to his australian home after bushfire season. His house was completely fine but his sons lego collection had melted !

Edited 1 time(s). Last edit at 02/05/2011 07:39AM by mlagana.

ok just had to confirm that story and turns out his neighbours house was on fire and the fire brigade arrived in time to save his house by spraying the walls, it was the radiant heat from the house next door that melted the LEGO so i should be ok sans bushfires.

sorry to hear news like that, i am glad they are ok

blog post

i got the idea from your problem, i cant test it yet, has i am still working on my repstrap. but i think i can test it a little when i get my new set of electronics.

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[mike-mack.blogspot.com]

that will definitely help it would be better if it came into contact with the barrel itself like this:

[www.thingiverse.com]

and possibly had more fins, like those big chunky computer heatsinks. i'm thinking of doing the same as lampmakers version above but trying to source out aluminium nuts and washers.

also i can't tell because of the kapton you might have done this but lampmaker has kinda filed away a section so there is a gap above the hot zone where the m6 goes thin, then above that he has still left lot of room for heat dissipation, which is this designs only con it i think you would lose a bit of Z distance.

not sure if this is con or pro but you are doing away with the ptfe and peek but gaining a small fan. i guess the fan would be cheaper and more widely available unless you machine the ptfe/peek yourself

Edited 1 time(s). Last edit at 02/06/2011 01:05AM by mlagana.

i did what i could with that i had, lol

thats most of my repstrap so far, but i will get there. it is not a perfect way of doing it, but i also didnt want to add allot of mass. my line of thinking was if i can keep the heat from going into the peek all the better.

its far from a refined idea, but i thought it would be worth a try.

i am not sure what there is for aluminium bolts out there, its pretty soft stuff, i am curious to see if there are any out there now.

if you can find a heatsink that will work better for ya, and its cheap give it a try cant hurt to try.

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[mike-mack.blogspot.com]

good work doing your extruder as you work on your axis, i kinda made the 3 axis work, then moved onto the extruder thinking it would be easy but it took up a lot of time and it's much harder to work on an extruder when it's all bolted down to the printer,

if your cartesian bot isn't ready yet i would suggest rigging your extruder up somewhere simple and make sure you can reliably extrude before bolting it down to your printer.

i have got heaps of heat sinks around, some big chunky ones with lots of little fins but i'm trying to work out a suitable australian hot end design so i can sell it along with my wades extruder kit.

and yes i was surprised to hear there are alu nuts and washers but my dad is completely sure and said he probably still has some somewhere. i can't find any and i'm thinking this could have been a few too many full moons ago. Now i'm wondering how hard it is to cast an aluminum parts, i would need to make a mold that can withstand 660 degrees.

i think you would be far better off to try to get some round stock milled down, it is cheap enough to buy if you can find it, but you might have to buy allot more than you need, but you can always sell them after.

i know one issue with casting aluminium is the toxic fumes so keep that in mind.

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[mike-mack.blogspot.com]

i probably won't go down that path. although if i can find my blowtorch i am probably test pouring it into this really strong silicone i have, the data sheet doesn't have any info on temperature ratings but i know it can withstand more than 300. alu is 660 or something so it probably won't work but you know.

thanks for caring about my heath, i pretty much live with a chemical mask on since i do a lot of plastic casting and sanding, and especially since i started printing in ABS in the same area i work without proper ventilation

you could always try lost mold casting, into a clay sand mix.

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[mike-mack.blogspot.com]

welll after a seven day heat wave today we were met with cold winds which was quite strange but printer seems to be working fine again.



Edited 1 time(s). Last edit at 02/06/2011 04:56PM by mlagana.

on hot days i lowered my working temp by about 5deg c at a time. on my rapman that is 225 down to 220deg c. One day when it was over 100F i lowered it all the way down to 200C. This is not my only printer, but it has been reliable and has the strongest extruder of all my printers, the lowest temp it will run is 198, the highest with a cork barrier in place of ptfe was 300c .


I always have warping issues when using the fan.

I still do not have a working solution other than lowering temp down 5 deg at a time till it works. not only with hot weather, but when it is humid too. I just know what temp to adjust it too, thankfully i do most prints inside my house that is temp regulated currently. It does nothing to help when it is humid though.. I think people in places that rain a lot will be dialing in the printer often. imho.

from this link you can find with a barometer and thermometer thermal conductivity of air.
[www.engineeringtoolbox.com]


i think it may have something to do with temperature equilibrium and the difference of cooling of the abs and the surrounding air, on hot days the plastic temp is actually higher when it is extruded and cooling on the surface. i also assume it is less important with smaller nozzles, but i have not tested it nor do i have data of that. just experience with changing temp of extruder by 5 deg on hot days. good luck!

i tried lowering to 240 but then it just wouldn't really extrude.

shame it went from so hot to all of a sudden 22 degrees, can't really give it an accurate operating temperature but 30 degrees and over didn't work.