1 Piece Printable Dry Box

• Prints as a single piece – no supports required.
• Holds 5 standard 1Kg spools of filament in a compact box.
• Handles large 2Kg or 3Kg spools as well as small 250g or 500g spools
• Requires only one standard A4 size sheet of acrylic – no cutting or drilling.
• Uses PTFE Glide Rails rather than rollers and bearings.
• Stackable – either straight vertical or offset for easier access.
• Filament travels directly to printer – no contact with outside air.
• Has conduit for wires for internal lighting.

There are myriad dry box solutions posted on printables.com. Most utilise some sort of plastic container (usually from Ikea) or involve specially cut and drilled acrylic panels.

This dry box is printed as a single piece, and other than a few hinges and latches, requires only one sheet of standard A4 size acrylic. Rather than complex rollers, it incorporates PTFE tubing (Teflon) glide rails. This means that any width of spool, from tiny 250g spools up to 3kg spools will fit (with a maximum diameter of 200mm). Five standard Prusament spools fit. It’s easy to change spools and you can print directly from the box to your printer without the filament ever contacting humid room air.

Parts required:

• 1             Acrylic sheet A4 size (210 x 297mm) 3mm thick
• 6-8        Bolts M3 x 8mm (or M3 x 10)
• 5            Bolts M3 x 20mm
• 1m         PTFE tubing OD6mm/ID4mm
• 3m        PTFE tubing OD4mm/ID2mm (optional)
• 1m         Foam weather stripping 5mm wide x 2mm thick

Printing:

Using Prusa’s (rather conservative) preset print settings it will take just over 24 hours to print but can be printed faster. The box and glide rails use about 900g of plastic. Use PLA or PETG.

Use variable layer height; much of the box is flat walls and a large layer height is fine, but some bits are sloped or have screw threads that can benefit from a lower height. Use a brim to prevent the corners from curling up. 

You'll also need to print 4 hinges, 2-4 latches, and, optionally, 1 strut. There are threaded holes for up to 10 latches and 2 struts so you can choose where to put them.

Of course, you will need a 350x350 bed.  Happy days XL and Voron owners!

There are two versions of the box, one (1 Piece Dry Box - Upper) has the filament holes on the main face beside the latches aiming slightly upwards.  On the other (1 Piece Dry Box- Lower) the holes are below the latches and aiming slightly downward facing.  The choice is up to you but it really only matters if you intend to stack the boxes - you'll want one upper and one lower.

Assembly:

• The walls of the box are quite thin (1.4mm). Depending on the quality of your print, you may want to spray the inside with a plastic lacquer to improve airtightness.
• Place the two glide rails end to end and insert a length of OD6mm PTFE tube into the two combined rails. Cut the tube to so the ends are flush (346mm). Remove the tube and repeat. Insert one of the cut tubes into the glide rail on the inside of the box. Install the glide rails in the bottom of the box (high side towards the front) using four 8mm or 10mm bolts, then insert the other PTFE tube.
• Optionally, install lighting strip (see below).
• Stick the 5mm wide weather stripping in the groove, ensuring no gaps or overlaps.
• Apply thin two-sided tape to the hinges and screw them to the box using 20mm bolts.
• Remove the backing film from the two‑sided tape and the protective film from the acrylic sheet. Place the acrylic sheet in the centre of opening. Clean the sticking points of the acrylic sheet with IPA. Swing the hinges to stick onto the acrylic sheet and press firmly.
• Using 8 or 10mm bolts, screw in the latches. Only two latches are needed but you may want to use four for a better seal. There are 10 latch holes for you to choose from.
• The acrylic sheet, opened all the way, will stay open by itself. A strut is necessay if you have stacked dry boxes and want to be able to hold it part way. Attach a strut using a 20mm bolt, left or right side as desired.
• Cut 7x lengths of OD6mm PTFE tubing. The pieces must be at least 15mm long but, if you make them +/-50mm, the extra length will stick out the front and act as a strain relief for the OD4mm tubes. Insert them into the holes in the front of the box.
• Cut lengths of OD4mm PTFE tubing. The length will depend on how your box and printer will be situated; the number will depend on what spool sizes you intend to use.
• Put a spool in your box pushing the filament out the nearest hole. Pull enough filament out to match the length of your OD4mm tube. Push the filament through that tube then insert the end of the OD4mm tube into the OD6mm tube. Feed directly to your printer.

The box is intended to handle five 1Kg spools. There are seven holes in case you want to use more, smaller spools. Plug unused holes. The box is not as airtight as a Tupperware container but, with a few packs of silica desiccant, your filament will be kept nice and dry.

Optional extras:

• Lighting strip: A 5V USB 0.5m LED strip can be bought for £4.99. The inside corners have conduit (4mm dia) through which you can run wires for the light. There are small dimples on the back and sides to indicate where to drill to access those conduits.  
• On/off switch: The conduit runs close to the lifting handles.  A magnetic reed switch in the conduit can be activated by a magnet placed in the handle hole. £5.99 for five.
• Filament labels: Small (6mm) squares hole on the inside lip allow you to insert labels.
• Hygrometer: Holders for round and rectangular hygrometers fit in the square holes.
• Stackable: The dry boxes can be stacked, optionally with an offset to allow easier access to the lower box. There is a small hole through the feet and upper slots. Insert a pins or bolts (2mm) to improve stability. 

Section analysis of the front left top corner viewed from the back:

<< Stacking grove

<< Lifting handle

<< Put magnet here

<< Conduit, put reed switch here

If you would prefer to use an Ikea storage box, check out these other options:

https://www.printables.com/model/378085-rollerless-ikea-dry-box

https://www.printables.com/model/8018-ikea-dry-box-4-prusament-spool-roller

https://www.printables.com/model/4326-ikea-dry-box-rollers-3-spool

(As you can see, I've been trying to find the perfect solution for quite some time now)