K2 Plus Exhaust

Updated morning of 3/19/26

Edit: I added a solid intake cover and poop chute door for printing high VOC filament. The intake cover used the existing hardware, the poop chute door flips up and out of the way when not in use. The door will need to be supergluse, hot glued of double sided tape for installation.  I have an in line 120mm inline fan https://www.amazon.com/dp/B07VYGQPCZ?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_16&th=1 

and set it to # 2 setting while printine ASA, ABS etc. The # 2 setting creates just enough negative pressure in the chamber to exhaust the fumes without dropping the chamber temerature.

I searched for an exhaust system that was easy to install, didn't require disassembly of the printer and required no supporters. I didn't fall in love with anything I could find, so I designed and built my own. All the bends are at a 45 degrees, no 90's.

I used extra screws to form thread the holes instead of using a tap. You could use a tap, but I decided I didn't want any metal shavings inside the printer. Use the center holes of the two outside (exhaust ports) as practice as they will not be used, to give you a feel on how to form thread a hole. The holes are based on a perfectly formed X based off the center hole of each vent. The center (intake) will need a thread in the middle hole for the intake/poop chute cap, a total of 13 #6-32 x 1/2 screws (plus 2 practice holes) holes will need to be form threaded. It took me a total of 4 extra screws for thread forming, the screws will wear down/out or collect material on the threads while forming. If there is metal or stripped threads on the screw after forming, grab a new screw. Only screw them in about 4 thread, the next hole screw in 8 thread etc as screws will wear down, going a bit further will get new threads onto the holes. You will need to put a little pressure on the screw for it to start. After all holes are threaded take a new screw and clean the threaded holes so you can start all the screws by hand. You could use #6 sheet metal material screws, but I'd advise against it, you'll get more bite with a #6-32 thread. I used PETG for all the parts, 15% infill and TPU 98A, any TPU should work, for the gaskets and 2 collars. The collector is made to accept a 4" vent hose. I have both right and left exit listed.  Left and right are facing the front of the printer, not the back. I used an inner and out brim on the tailpipe and collector. The manifold and intake cap just a skirt.

I used shay's design for the waste basket and holder. I scaled the waste basket to 98% and shortened the height to 150mm

https://makerworld.com/en/models/1227123-k2-plus-right-poop-chute-with-removable-bin#profileId-1245142

The G-Codes files for the gaskets and collars were printed on a Neptune 4 Plus, 98A TPU with a .6mm Nozzle. Use the STL files to print them on your machine, nozzle size and TPU. Printables made me put something in that folder. Everything else was printed on the K2 Plus with a .4mm nozzle.

Installation and Assembly Instructions

Materials needed:

13) #6-32 x 1/2 Philip Headed Pan Screws (plus 3-4 extra for thread forming)

15) #6 washers 

3) #6-32 X 2" screws (These are for the Intake/Poop Chute cover

4) 3mm x 5mm brass inserts (these go into the collector and holds the tailpipe

to the collector)

8) 3mm X 12mm screws (4 to attach the poop chute cover to the poop chute base and 4 for the tailpipe to

collector)

1) Piece of 3M 1/2" wide (or whatever size you may have about 8-9" long (for

sticked the poop chute to the back of the case)

4) 3" narrow hose clamps

Assembly Instructions:

Remove the 2 screws that hold the poop chute to the back of the case, these 2

hole will be used to hold the poop chute/intake cover in place.

Install 2 (3mm) screws in the outside upper holes to help hold and align the

gasket and manifold in place. Install the 2 screws into the hidden holes (under

the manifold elbow), just enough to hold it in place, start the other 10 screws.

Snug all the screws. DO NOT OVERTIGHTEN THEM! They just need to be snug.

Align the Poop Chute to the intake port and with the 3m tape installed stick it

in place. Install the poop chute cover with (4) 3mm x 12mm screws 

Install the intake/poop chute cover and with (3) #6-32 X 2" screw. One in the

intake center hole and 2 where you removed the 2 poop chute screws.

Slide the TPU collar over the manifold. The collars are under sized by design,

put the build plate side of collars facing out, the tailpipe and collector have

more taper and will be easier to install. Slide the TPU collar half way onto

manifold and clamp it in place.

Slide a clamp onto the tail pipe and slide the tailpipe into the collar.

install the clamp just tight enough so it don't fall off. Slide a hose clamp

over the collector and slide it into the collar. Install clamp just tight enough

to hold it in place. Align the tailpipe and collector install the screws (3mm x 12mm) that

connect the tailpipe to collector, tighten them once you have all the screws

started. Push the tailpipe/collector tight against the manifold and tighten all

clamps