Hi, good afternoon, I am an Electronics engineer specializing in Power electronics and PCB design, I first answer the requested information:
* The cheapest board thickness PCBway offers is 1.6mm, that is perfectly fine for power boards unless a thin board is needed for specific reasons.
* For high power boards, instead of using the standard 1oz (35um) copper thickness, thicker copper layers can be used to decrease the track width. Common cheap options are 2 oz and 3 oz. This is true for low-frequency designs, for high frequency it is preferable to use several thin tracks in parallel to account for the skin effect.
* Two layers are enough for the majority of power PCBs, unless sensitive analog or digital devices are used. In that case, a 4-layer stack is preferred since it allows to have a better ground plane and coupling, minimizing crosstalk.
* I normally use a 20 C allowable thermal increment, for that case using 10 mils of track width per amp of current works well (1oz), according to many track width calculators and my personal experience. This, of course, can be discussed.
* There are several design rules that the design needs to comply in order to be successfully manufacturable by PCBWay, two of the most important ones are the minimum track width and spacing, which is 4 mils, and minimum via hole/size, which are 8 mils and 20 mils.
Freelancer.com doesn't allow me to place a larger bid, so please contact me to discuss this further,
Regards,