High current PCB prototyping service

[Sigmoid]

Hey,

I'm looking for a reliable prototyping service that does high current (>2-3oz) 2 sided PCBs. The ones I know only do 1oz, or at least that's what I managed to extract from their website.

Any suggestions?

[LukeW]

It might be faster/cheaper/easier to only use 1oz copper from any old board shop, leave the solder mask open across the entire high-current power traces, and then thickly tin them with solder?

[ovnr]

Seeed does 2 oz copper, but it's somewhat ridiculously expensive compared to 1 oz ($40 for 10 pcs of 5x5 cm boards vs $10 for the same).

If it's just for prototyping, leave off the soldermask and add plenty of solder, as LukeW mentioned. If not enough, consider soldering on some heavy copper braid or something.

Of course, if you must have heavy copper on a SMD board where it's simply impossible to bodge something on, you'll just have to cough up the money.

[Paul Moir]

That's not ridiculous at all!  AP Circuits in Alberta goes from $55 for 1oz to $577 for 2oz.  Guess which process is optimized for prototypes! 

[coppice]

Seeed does 2 oz copper, but it's somewhat ridiculously expensive compared to 1 oz ($40 for 10 pcs of 5x5 cm boards vs $10 for the same).

You will frequently see a similar price differentials for anything which is not the highest volume option, like choosing your boards with a specific colour of solder mask. Customisation costs.

I see a 2oz option for most of the Chinese prototype board makers. If you want something even thicker your choices tend to narrow rapidly, but quite a few people doing high current work choose 2oz these days.

Note that 2oz has its downside. Its so good at conducting heat that you may need to be more liberal with the use of thermal lands. However, the holes in the copper around the thermal lands can defeat the whole purpose of using 2oz in the first place.

[Sigmoid]

Thanks. Seeed looks pretty cool. Also, it seems that 20 boards cost pretty much the same money as 5 boards... maybe I'll try selling the surplus on eBay.

I got a "free" ATX supply with my Printrbot, and decided to break it out into a high power bench PSU for when I'm not 3d printing. I'd like to make a break-out board that takes a few molex connections, exposes the PSU's rails on post terminals, and does the extra stuff you need to do to keep an ATX supply happy.

There are a few ready-made ATX breakout boards you can buy, but those are low power, one I've seen is even fused for 1.5A. The PSU can supply 30A on the 3.3V rail, 25A on the 12V rail, etc... so since I have a high power SMPS, it would be nice to keep the possibility of supplying high power from it.