Rubbermaid 21 Cup Dry Box

4/9/2021 - Uploaded the Base with 2 different sizes for nuts, 5.6mm and 5.7mm, incase your printer over extrudes a little.

11/30/19 - Updated Spool to use 2mm walls for easier printing and printing instructions for spools.

Humid air is lighter then dry air. Is the dessicant in your dry box at the top?

All filament absorbs water, even PLA.

This information is in a TXT file in the download.

Rubbermaid 21 cup filament dry box by OneEyeDesign

This uses the Rubbermaid 21 cup dry food container
Part# 7M74.

Humid air is lighter than dry air, so it's best to have
the dessicant at the top of a container you want to
keep dry. I designed the dessicant box with a quick release
mount so you can easily change rolls and take it out to dry
in a dehumidifer.

I have included 2 versions of the base, one uses heat set
inserts in the feet. The other has holes in the feet
roughly 6.5mm wide so you can insert the screw head and
use nuts on top. The rest of the parts all use heat set inserts.

The rollers will need to be sanded at the Z seam so the filament
can roll easily without stopping the roller. A large nail
file with a course and fine side works great.

I used 1/4 inch PTFE tubing for filament transfer from the dry
box to the printer because it allows for less restriction. You
can buy it at any Home Improvement store in the plumbing aisle.

I have included a mountable 1/4 inch PTFE through coupler to pass
through a 2x4 or other type of enclosure. You put a piece of PTFE
in between the two mounts.

Roller stand hardware:
(4) 608 skateboard bearings, remove shields and clean out heavy
grease to make them spin easier. Lube with light oil (3 in 1 oil).

(4) M3 heat set inserts OD 5.6mm (initeq heat set inserts short)
https://www.amazon.com/gp/product/B077CJV3Z9/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1

(4) M3 screws 10mm or longer

PTFE fitting Hardware:
(2) M3 x 12 screws
(2) M3 heat set inserts

Dry box Hardware:
(2) M3 x 16 screws
(3) M3 x 8 screws
(5) M3 heat set inserts

Dry box drill jig:
Line up jig outside box, top of T against lip
and center the bottom with the measurement graduation.
Drill with 7/64 bit

1/4 PTFE drill jig:
Line up jig outside box, top of T against lip
and center the bottom with the measurement graduation.
Drill with 7/64 bit. After installing both sides
drill center with 3/16 bit so holes line up.

1/4 PTFE caps
One is closed and one has a hole for filament so you don't have
to open the dry box to reinsert in printer. I don't recommend
using the cap while printing because it restricts movement.
You may need to use a 5/64 drill bit to open the hole up.

Print settings:
These are the settings I used, change as you see fit.
No brims needed unless you have adhesion
problems. I use buildtak on a whambam bed.

All parts use:
0.40 nozzle
0.50 line width
0.20 layer height

~ denotes a change from the last part

Base
6 top layers
6 bottom layers
3 perimeters
Grid infill 20%

Sides
6 top layers
6 bottom layers
3 perimeters
Grid infill 20%
Min infill length 3mm

Rollers x 1 (1hr 50m)
Slower due to layer time restriction
50mm/s
0.5 line width
0.2 layer height
6 top layers
6 bottom layers
*5 perimeters
Infill doesn't matter

Rollers x 4 (much faster printing, 2hr 12m)
50mm/s
1.0 line width
0.2 layer height
6 top layers
6 bottom layers
*5 perimeters
Infill doesn't matter

PTFE fittings
6 top layers
6 bottom layers
~3 perimeters
Grid infill 20%

Dry box
Clear PetG so you can see dessicant change color
and so it's heat resistant for drying in dehydrator
~10 top layers
~10 bottom layers
~4 perimeters
Grid infill 20%
Supports, build plate only, only needs it at
front of box, see pictures.

Dry box lid - if you make it solid the surface comes out rough
~4 top layers
~3 bottom layers
~2 perimeters
Grid infill 20%

Dry box mount and washer
~6 top layers
~6 bottom layers
~3 perimeters
Grid infill 20%

Helpful Tips:
ALL filament shrinks after cooling.
The amount of shrinkage depends on the type of filament.
PLA shrinks about 0.25%
PetG shrinks around 0.35%
Taulman 910 shrinks 0.31%
That means a PLA part printed at 200mm long will be short by 0.5mm.
I scale all my stuff in the slicer to 100.25% to compensate for most shrinkage.
Measure for yourself if you don't believe me!