BentoBox v2.0 5015 pull-configuration case+shroud

Negative-pressure (pulls air) 5015 fan case and shroud for the BentoBox v2.0. 

The new V2.0 BentoBox design is great, however I do not agree with the original authors fan choice; 4020 axial fans have very low static pressure of around 7mm H2O while in contrast 5015 radial (blower) fans can deliver up to 30mm H2O. 

What about the other 5015 designs? All of them use the fans in a positive-pressure/push-configuration which is much less effective for an air-filter. Commercial HVAC systems use pull-configuration for this very reason.

So how did I fit 50mm fans in the slim BentoBox tower? By increasing the width of the base by 8mm. The tower sits 2mm closer to the wall now and still has around 4mm clearance to the heatbed. The new fan shroud reduces this width back to the original size so all other parts of the BentoBox v2 fit on top. Additionally, I increased the total height to 25cm so the intake is closer to the heatbed when printing low-height models.

Assembly-Animation: 

Below the fans sits an electronics bay with enough space for all cables/connectors and an LM2596 step down module or similar. I recommend using a MP1584EN based one as it is very difficult to source genuine LM2596 modules and counterfeits can have bad voltage ripple. Power cable can be routed outwards on both sides. Optionally cable holes can be plugged with the provided cable hole plug, print it out of soft to medium TPU (85-92A). You can use it on both sides, cut the one with the cables from top to middle with an exacto knife to have a slit for the cables.

I've also included a version of the fan case with a cut-out for a generic SPST rocker switch. The fans are screwed down with M3x18 screws and M3x4 heat inserts. Both the cut-out and the heat inserts can be easily adjusted to your needs by simply editing the provided STEP files.

Printing: 

Print from PETG/PCTG/ABS/ASA/PC or anything else heat resistant. Use 85-92A TPU for the cable plug. The 2 front and the switch hole of the case may require (tree-)supports depending on your overhang settings.

Materials: 

• 2x 5015 radial fans (12/24V)
• 12x 4x2mm or 6x3mm Magnets
• 4x M3x4 heat inserts
• 4x M3x18 screws
• optional - 1x Step-Down module (LM2596/MP1584EN)
• optional - 1x SPST rocker switch

Changed weak and noisy 4020 axial fans to much stronger 5015 blower ones. Increased total tower height, added option for 6x3mm magnets, added cutout of a rocker switch.