This is a set of model files to build a variable desktop DC power supply. I've decided to build this because I did not like how my store-bought DC power supply did only had 1 set of binding posts. I often work with loose strands of conductors and/or USB interface, and I wanted a compact power unit that can be put right next to the project piece I am working on.

One feature I want to make a comment on, is the use of the banana plugs. I did not have any spring loaded connectors on hand to use with loose conductors, and I thought I could just use the thumb screw portion of the banana plugs to clamp wires down, which is why you see it installed upside down and is recessed below the rest of the surface.

Who this is for

This is for those who have a buck boost converter laying around and want to have some fun building something with it. If you legitimately need a DC power supply, I recommend buying one instead of building as it's much less work and you will end up spending more money acquiring one or two pieces of little things.

What you need

Note: Use the included fusion 360 file to make necessary adjustments.

Note2: I do not have any affiliate relationships with the sellers of the products that I have linked below.

Buck-boost converter w/ display

Requirements:

• Any unit that has similar dimensions as the one I used in the build.

Cutout size: 75.5 mm x 39 mm

Thickness: 35 mm

Product link: [https://www.aliexpress.com/item/1005005044026039.html](https://www.aliexpress.com/item/1005005044026039.html) 

Other remarks: you are most likely going to use thinner gauge conductors inside the unit as the space is pretty limited, so don't get hung up on the power ratings. In fact, I would not be putting more than one or two amps thru this system.

External DC power supply

Requirements:

• Has enough power to drive the buck-boost converter you have chosen.

Product link: [https://a.co/d/3ICd95j](https://a.co/d/3ICd95j) 

Other remarks: Something like 12V 2A should be enough for most lightduty work. 

Binding posts

Requirements:

• The M4 shaft needs to be 12mm or longer to be able to fastened down & leave room for the wiring job. 

Product link: [https://www.aliexpress.com/item/1005005610222281.html](https://www.aliexpress.com/item/1005005610222281.html) 

Banana plugs

Product link: [https://www.aliexpress.com/item/1005006373747442.html](https://www.aliexpress.com/item/1005006373747442.html) Type C

DC barrel connectors

Requirements:

• Need two (front/back)
• Cutout diameter of 9.5-10 mm
• Outer diameter of 13.8 mm or smaller

Product link: [https://www.aliexpress.com/item/1005005906948433.html](https://www.aliexpress.com/item/1005005906948433.html)  Type 3

Other remarks: The one that I linked is not so great. Find something else with a similar size.

USB-C port

Product link: [https://www.aliexpress.com/item/1005005797553973.html](https://www.aliexpress.com/item/1005005797553973.html) 

USB-A port

Product link: [https://www.aliexpress.com/item/1005005967989044.html](https://www.aliexpress.com/item/1005005967989044.html) 

Other misc things

• M3 bolts, nuts, and heat-set threaded inserts
• Wires – 16-18 gauge. I have personally used 14 gauge but that was a super tight fit inside the small enclosure and not worth the effort.

Printing instructions

• panel.stl: print with the face down
• shell-left.stl and shell-right.stl: with the sides facing down. Printing them separately eliminates the need for using support materials. If you do not like having seams in your finished piece. use the ‘combine’ command within Fusion 360 and save the new STL file.