DIY filament storage bag vacuum pump

I've used small disposable USB vacuum pumps up to now but I thought I'd try my hand at making something maybe a little faster, serviceable, and perhaps longer lasting. Aside from that I've kept the bottom suction seal larger than the small pumps as it stands on it as a stable base.

It works great on the bags I have, both eSun ones with a hard plastic valve, and others without that. I'd love to hear any feedback once you've made your own, and ideas for improvement.

These pumps aren't electrically polarised making the circuit super-simple. No matter which way you hook up the wiring it won't reverse the airflow.

Hardware

• 12V 555 high speed air pump

• DC022K style 2.1mm DC socket

• 4x M3 screws (10-12mm) & 4x M3 heat set inserts

• Donor 12V wall wart 1.5A (I used one from a Roku/Telstra TV so also needed a replacement 2.1mm plug to match)

• a short length (approx 83mm) of air line 10mm outer, 6.5mm inner

• 20mm generic rocker switch

• shop supplies inc wire, solder, heat shrink

The 12V 555 pump I bought says it draws 800mA on the datasheet, but I measured around 1100mA when stalled, so a 1.5A or better power supply is best.  There's plenty of room inside to add a boost or buck regulator too if your donor wall wart isn't natively 12V.

I also added a blue LED and current limiting resistor inside the case across the power to remind me it was plugged in.

If you want to add an external LED, or use a different switch I've included the STL of a blank lid to make your own to suit - just add negative volumes to cut holes in the slicer.

I tried a silicone tube initially, but it flattened when the pump turned on - the air line I bought is also sold as PU air tube or pneumatic hose. Aside from what I had laying about, the needed shopping list was found cheaply online

Assembly

The pump fits small-end down into the enclosure body and is held in place at the bottom, and held vertically by an inserted brace, pressed down by the lid.  Once the pump is pushed into place there's a channel for the power wires to be pushed up the opposite side of the body to the air inlet, soldered in place at the bottom end on the pump, place the top brace on top of the pump, then wire up the rest. Here's what that looked like on mine:

The air line pushes into place between the pump and the base, as you afix the base. I started with a slightly longer length and trimmed it to suit.

Printing

The screw holes on the lid are countersunk so you might consider supports to keep those clean. The resulting plugs are easy to push out from the the other side with an M3 screw. Everything else prints without supports.

For the base and TPU suction seal use 0.2mm layers for accurate screw threads.

For the two made in these photos I used eSun grey TPU 95A for the suction seal. A more flexible material if you have it might be even better. For the hard plastic parts I used eSun PLA+ silver and blue, and Elegoo PLA galaxy black.

I tried PEBA 90A for the black suction seal in the final photo. It still stands up okay. I don't think going softer than 95A is any huge benefit.