13.8V 750W HP server power supply.

This model is designed to be printed in PETG or ABS and used to convert inexpensive Hewlett Packard quick swap power supplies into usable 13.8V power supplies for ham radios and similar type electronics.  

I purchased my HSTNS-PL18 power supply for just 14 dollars off of eBAY delivered.  They are very well built power supplies that very good regulation and over voltage protection that would cost several hundred dollars to buy equivalent quality construction/circuits but are readily available and cheap as they are proactively replaced by mainframe server operators well before end of life so any failure doesn't end up causing a down server or lost data.  From what I understand several different models of power supplies will fit the same place but I have only used HSTNS-PL18.  

These power supplies need a minor mod via a removed and bridged SMT resistor pads and a switch added between two of the pads but that is linked in the original Hackster page.  Warning, if you don't know what you are doing you shouldn't be doing this step.  The capacitors can be very dangerous even unplugged, you open the power supply case at your own risk.  I will not hold your hand through this.  

I used M3 heat inserts in my version to do most of the assembly along with an assortment of M3x8, M3x10, M3x16 and M3x20 button head screws I had on hand plus a few M3 nuts and washers. Also instead of just a few zip ties holding it together there are proper cross clamps top and bottom.  The Zip ties at the back on each side is still necessary but just to keep things from sliding forward and back.  If the hole is 4.4mm it gets a heat insert, there should be 4 on each rail, two on the back side of the front panel and 4 on the front panel top.     ruthex M3 Threaded Inserts VORON - 100 Pieces RX-M3x5x4 Brass Heat Set Insert for Plastic Parts - Metric knurled Nuts - Insert by Heat into 3D Printing Components: Amazon.com: Tools & Home Improvement

I used a 1/4 micro switch, mine is locking with 20 gauge wire and a few small pieces of heat shrink slipped over the switch contacts so it cant touch the power supplies case.  I used an NKK M-2011 switch which I use as they are very high quality but any on/off 1/4" micro toggle switch should fit.  There is no amperage flowing through it, it just bridges two pads on the PS to make it fire up and put out power to the +/- pads on the front.  

Obviously it uses ATC fuses of the desired amperage and I used Thomas and Betts 14-16 gauge female spade terminals with the insulating collar removed and an actual good uninsulated terminal crimper that uses a proper die not one of the cheap stamped steel crimpers that more crushes the terminal than forming a proper crimp.  I did need to tweak the post crimp terminal slightly as its a tight fit where it snaps into.  This tight fit is necessary to keep the terminal in place to interface properly with the fuse inserted into a pair of them.  It took 10 redesigns to get everything perfect, using other parts may require slight modification with a needle file or small sharp mini chisel.  

I used 14 gauge fine stranded wire for mine.  I would suggest that size to handle up to 15ish amps per circuit. 

The power pole connectors point backwards on the top fuse block. I highly dislike forward facing terminals because the wires then hang out in front of desk shelf.   I use genuine Anderson power pole connectors and this is sized for them and is snug, I don't know if knockoffs will work.  All my radios have their connectors at the back.  I used the 30 amp terminals. 

The power distribution box that shares some of the same parts is at 

I used 3mm heat inserts and cross bars to assemble vs just a few zip ties greatly increasing the strength.  I also moved the power pole connectors to the top of the case that  point back to better manage wiring and increased to 3 outputs.  I also added ATC inline fuses on the front, one for each output to protect the connected electronics.