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PCB Trace Width Questions Answered

Hello instructioners,

So i am working on a PCB to use my XBOX 360 power supply as a standard 12volt 16 amp without hacking it apart. I've taken the female plug from a dead Xbox and I've recreated the layout in ExpressPCB. my only issue is being that its 16 amps @ 12volts is the trace widths to hold that much power are ridiculously wide we are talking 7mm or there abouts. I used several different online calculators to determine trace width. 

My question is..  how small can i get away with for traces and still get 16amps.. is there a way of bridging the front and back side of a 2side PCB to allow for more amperage on smaller traces? i am really at a loss here. since my PCB is set at 38mm by 38mm and the connector size is 27mm long by 23mm wide. with 7mm wide traces i can't connect all the power pins together and all the ground pins together and route them out.

Now i realize the 16amps is max draw but i'd like to plan for a max draw situation that way i feel confident enough to not have to check it all the time to make sure its not melting. Below is an image of the current board in Express PCB the labeled Thru-hole are connections i will need to make for this all to work. the other remaining holes are for mounting the female jack securely.

The three yellow boxed connections are 12v+
The three greyed boxed connections are gnd
ENG is bridged to +5 to make the XBOX PSU provide 12v


You could run half the trace down each side and connect it by vias. Or you could not use traces and just put in big pin holes and solder in some PCB pins and connect them with larger gauge wire.

i'm new to designing my own pcb. and i will be etching the proto boards myself. i've not heard of the vias method. any extra info?

Ahhhh. It's a two layer method, which is more difficult if you're etching it yourself. I'd suggest using PCB pins like these and some suitable wire:


nice. idea what i ended up doing is flooding the traces with solder to make them extremely thick, its been powering my HTPC for a while now. Its Triple core AMD on a ASUS mini-itx with a 60gb SSD and a laptop blu-ray reader.. all tucked inside a 1986 Nintendo Case

any chance of the file so i can see if i can get one made

You'd get away with 3.5mm tracks, for a 30C rise, which would be quite acceptable on FR4 2oz board.