This enclosure doesn't actually work for high temp materials, does it?  

RE: This enclosure doesn't actually work for high temp materials, does it?

1. Do not run air filter during print. That pulls out all nicely heated air. Just keep that enclosure closed until the end. then start the filter for a couple of minutes, to clean the enclosure before you open the door. 

2. Maybe build yourself a small heater? I made one with: - MeanWell 12 Volt 11 Amp - PTC heater from Aliexpress (about 100 Watt)- Thermo switch (80 degrees C) build into the heater (to avoid burning the house when something goes wrong :-)- Thermostatic controller to set the temp. - Is placed in the enclosure. 100 Watts is not much, but enough to heat a 60-60-60 enclosure. As soon the printer gets on higher temp. It is just enough to keep it the temp high enough. 

RE: This enclosure doesn't actually work for high temp materials, does it?

I also had more trouble than I expected printing Prusament ASA on a MK4 inside the Prusa enclosure.  I'm used to printing ABS, and had no problems printing a full set of MK4 parts in ABS.  For my MK3.9 I wanted the parts to be in Prusa orange, so I thought I'd give their ASA a go.  I'd assumed that ASA was like a 'better' ABS, and would be easier to print, but I found it harder.  My print settings were set up for strength - 4 perimeters, 40% cubic infill, 5 top and bottom layers, so perhaps these made for a more challenging print.  My initial attempts had a fair bit of lifting on the bigger parts, despite them not being what you'd call big - the x-end-motor gave me the most trouble.  In the end I threw everything at it and got a good print:

• 275° nozzle temperature - that's a full 15° above the Prusament profile.  I'm using an ObXidian nozzle and in other tests I found it took an extra 15° to get back the full shine on PETG parts compared to a brass nozzle, so I carried that finding over to the ASA.  ObXidian is brass with a steel core, whereas Nozzle X is all steel, so I'd expect Nozzle X to need at least as much extra temperature.  But I'm conflicted by this setting - Prusa advise that "The main disadvantage of ASA is significant warping caused by temperature differences between the model and its surroundings", so perhaps a lower nozzle temperature would decrease that difference.  I'm pretty sure the higher temperature helps with first layer adhesion though, and I don't have enough experience with ASA to know if a lower temperature for the other layers would be better.
• Bed temp at 115° for the first layer and 120° for the others.  I haven't plugged all the holes in the enclosure - I think heat loss through the panels is likely a bigger effect (the doors certainly feel warm to the touch, so will be losing heat).  I think a few degrees extra on the bed temperature can easily compensate for any heat loss through those small holes and gaps.  My enclosure got up to around 37° during the longer ASA prints.
• 10mm brim
• A thin layer of glue stick, smoothed out with a wet paper towel.  You mentioned that you had ok results with glue stick, and personally I've found ABS prints much more reliably with glue stick, so I don't consider that the enclosure removes the need for it.

RE: This enclosure doesn't actually work for high temp materials, does it?

I print ABS almost 24/7 on four modified Prusa MK3S+ printers. I print large parts (transport cases) approximately 20cm x 19cm and 200 grams of material. I print them on a prusa textured sheet, with no brim, no skirt, and with no glue. Once printed, I let the bed cool down to at least 75°C and the part comes off with just a touch of the finger. I can print one part after another without glue, without cleaning the bed, or using a spatula, and I also get a nice textured finish on the base. The configuration I use is as follows; Chamber at 60°C, bed at 115°C, and hotend at 265°C. I use standard parameters and speed from Prusa Slicer for ABS (it's not convenient to print fast), layer height 0.2mm, and a 0.4mm nozzle. Each chamber is shared by two printers with a 600W heater controlled by a digital thermostat. Modifications made to each Prusa; PSU mounted externally using thick cable with XT90 connector (40 amps). This is important so that the voltage does not drop below 23V nor does the contact overheat at the joint. All PETG parts were replaced by ABS. The hotend NOCTUA vent was replaced by a SUNON (much more airflow needed to prevent CLOG). Replace the EINSY box with a big one to improve ventilation. It is also essential to add a SUNON fan to the EINSY box (this way the temperature of the EINSY stays below 65°C when the chamber is at 60°C). Then you have to add a fan (it could be the NOCTUA) to the Extruder motor and a couple of adhesive heatsinks to the X and Y motors. As additional improvements, it would be advisable to change the extruder to a BONDTECH BMG (with a heatsink on the pancake motor of the extruder) and instead of heatsinks, use fans for the X and Y motors. Why use a Bondtech? Because for strange reasons that I am not aware of, the filament sensor fails in the Prusa extruder at chamber temperatures of 60°C (I suppose that ABS parts refract some infrared light due to heat and that interferes with the sensor, which does not happen with the Bondtech's SLS material). Also, the pancake motor of the BMG better withstands the temperature. I also recommend changing the Y motor to a MOON motor, that way you won't get false triggers from the CRASH DETECTION system. As I said, printing fast and with low hotend temperature causes the filament to cool too quickly when leaving the nozzle, which increases the risk of warping. Regarding ventilation, I don't use any type of filter, but I have a medium-power air extractor venting outside. Since I don't use a filter to capture ABS particles, a little ABS dust accumulates in the printer, but it's easily solved by applying compressed air occasionally. It's not a serious issue at all. Unfortunately, the Prusa MK3S is no longer in production, and I don't believe the MK4 would be suitable for this use, as its electronics operate hotter than the old EINSY, and I suppose it could exceed 70°C under the same conditions. Additionally, the extruder has very poor ventilation (the fan doesn't have enough airflow, and the heat break isn't adequately dissipated with grease). Furthermore, the fan is difficult to cool because it's located behind the extruder. Also, input shaping isn't recommended for the reasons I explained about speed (perhaps increasing the chamber temperature even further, say 70°C and above, could allow for faster printing, but it's no longer feasible on these types of printers without making new modifications).

RE: This enclosure doesn't actually work for high temp materials, does it?

I share a picture of my mini abs farm

RE:

Hi everyone! I had to stop looking at this thread a bit because I decided that if I was going to go further with trying to get ASA printing on here, it'd probably be easier to have the printer able to handle higher temps from the start and then see how much that helped. So instead of printing the ASA parts for my printer myself, I had my friend do it on their Voron Trident - and around 3 months ago finally built my MK4 with them (after having to go back once because I forgot to resize parts, lol). After that, I got determined to make this thing work and while I did end up having to get some insulation for the enclosure - I'm happy to say my printer now does a pretty mean job of ASA prints, and there's not a gluestick in sight!

Surprisingly, I think the setup I ended up with is actually different from the solutions I've seen on this thread and I wanted to go over how I got stuff working a bit for other people who might be struggling getting this working. The first change I did was, of course, adding insulation to the enclosure. I wanted the insulation to be removable so that I could switch from a really hot environment to a more normal environment with the top of the enclosure open for less technical materials, so I've literally just been using some radiator foil I got off amazon and cut up into a bunch of parts that I stick to the outside of the enclosure using magnets. Thanks to the note about the panels losing heat that Chris Hill pointed out (you were 100% correct by the way), I cover all sides of the enclosure with panels on them and the top - and this immediately made an enormous difference in the temperatures I was able to hit. It still takes a while for me to heat up the enclosure, but just using the bed heater I'm able to reliably get temperatures of 45°C+ and hold them throughout the print. This absolutely has made a enormous difference. But, my prints still proceeded to lift - but far more predictably now. So I did more research, and discovered the next issue:

The MK4 toolhead by default creates a draft over the print bed, and I was able to determine this was one of the issues I was hitting simply because when a part lifted it would always lift in the exact same corner. I was sort of hoping I wouldn't need to try other cooling solutions, but I went ahead with printing these parts:

https://www.printables.com/model/692672-mk4-extruder-fan-duct-tweaked-version (redirects draft from the open-area between the heatsink and the back of the X carriage)

https://www.printables.com/model/456127-hotend-fan-shield-for-prusa-mk4-eliminates-turbule (redirects draft from the front of the heatsink fan)

https://www.printables.com/model/588524-mk4-bi-directional-fan-duct-lightweight-and-effect/comments (more even part cooling, there's a more interesting fan model I've seen around but I have yet to get it to print properly)

And I couldn't believe it, but after modifying my toolhead with all those pieces, I gave a shot at trying to print spares for some of the MK4 parts I had issues along with a large batch of parts for my upcoming positron kit (minimal to no brims here!!). And it worked, wonderfully! In fact, out of the positron kit I think I've only found a handful of parts that even needed a brim. I've thrown a number of other models at it since, even the one scientist model that polymaker has, and the results I've been getting are basically "it sticks like PLA but wants a brim slightly more often".

I should note too: I've had success with Prusament ASA (stock profile), and PolyLite ASA (Bed temps 100°C-105°C, extruder 260°C). I also do print with the air filter on, however: in my own testing I've found that the enclosure does not heat up anywhere near as consistently without the fan going, and I'm fairly confident that it does seem like prusa did a pretty alright job in making sure that the air blowing from the filter doesn't go onto the bed - but mostly goes under the bed. I decided to keep the air filter because of that, along with the fact that it seems like a lot of the vorons I've seen use fans under their print beds for the same reason. Also, for the print surface I generally go between my Satin Prusa sheet for easier prints and my Textured Fabreeko Honeybadger sheet for everything else (again, no gluestick). I don't recommend using Prusa's textured sheet in this manner because it's not as good at surviving ASA without a gluestick, but fabreeko's seems to work great for this.

The one issue I have seen with the air filter is that I am fairly sure there is a draft right in the front of the enclosure where the doors are, and I believe it's only near the very edges where air gets blown up the side of the enclosure from the bottom. At some point I'm going to see if I can figure out some way of fixing this, though I may try to make an enclosure mount for my newly acquired thermal camera first so I can actually confirm this with a bit more evidence. Frankly though, my setup is working wonderfully enough I don't think I care much :3.

So yeah, lots of heat and make sure your cooling isn't wonky - and you've got a prusa printing ASA ♥