Plastics absorb water believe it or not, Nylon is one of the worst, then ABS, then PLA, you can dry out the ABS and Nylon in the oven or a food dehydrator but the PLA tends to break down after the moisture absorption and then drying it out and printing, according to the studies I have read if you use PLA that has absorbed moisture that you only get about 33% of the strength out of the plastic that you would have if it was kept dry.
Now I don't mean soaking it in water, I am talking about it just pulling moisture from the air, I stole the cake cover from on top of the fridge since it has been almost 5 years since we have made a stacked round cake, then made an adapter for the side of it to connect a bowden tube between it and the extruder, and then from the extruder to the hotend so the only place it can pull moisture from is the opening in the extruder where it never sits long enough to pull any moisture from the air, I would have to let it sit without printing anything for weeks for it to affect it and it would only affect that small section, but without this system by the time I was 1/3 through a 2lb roll of filament that the rest of the spool would be pretty wet, nylon only takes 2-3 days to absorb enough moisture to affect the print so imagine it sitting there for a month as you are using the roll.
A mounting bracket for a moisture absorbent gel pack that I picked up from amazon, when the beads turn green you bake it in the oven until they turn orange again to recharge it, that will absorb all the moisture in the spool chamber.
Mounted in the top of the lid.
It is a bit overkill size wise but oh well, it will work well, I liked it for it's clamps, my original idea was an ice cream bucket but it was not quite big enough.
So the plastic filament is pulled through the tube off of the spool.
This is the extruder that pulls the filament from the spool and pushes it to the hotend, this is where the bowden tube really comes in, it acts like the brake/shift cable on a bike, both ends of the tube are attached securely then that allows the plastic to be able to be pushed through and be guided by the tubing allowing the hotend to move around and still be fed plastic.
I used a zip tie to hook the bowden tube to my wiring harness because other wise it will move/flop around while the plastic is pushed and pulled causing slop, it is the same reason your brake/shift cable on your bike is attached to the frame every so far.
Then it pushes the plastic down through the hotend, the fan keeps the upper portion of the hotend cool as you do not want the entire thing hot just the tip, if the plastic starts to melt higher in the hotend then it should then it starts to jam and clog, the aluminum block you can see under the fan that has the two red wires going into it is the heater block, that's the section that you want to get hot, that and the tip, then everything above that is to be kept cool if you want optimum performance.
