Cheap PCB prototpes?

Then use quick set epoxy to mend it!

..or tell them to step and repeat.

Preliminary quote from YouPCB for three (minimum) boards 0.5x1.4 inch, FR4 0.047 thick, no stencil, no soldermask, no test $12.00 + $15.00 shipping. Needs Gerbers. Preliminary quote from PCBcart for one board all else same was $74.64 one-time tooling, $20.67 for the one board, $1.36 each at 50, no mention of shipping charge. Can use Eagle files.

SMT both sides, 4 holes/vias.

For just a few boards and near zero prospect of more later, YouPCB kicks butt. For a few boards PCBcart roughly compares with ExpressPCB and at higher quantities kicks butt. Both offer a range of PCB thicknesses;a possible advantage over ExpressPCB.

DHL moved a package for me to China in two days. Customs can take from an hour to infinity (that is where they decide one can't use the item and so keep it*).

• Happened to a shipment of a computer to someone in Ethiopa; i outfoxed them the next time by sending the 2nd one in parts which substantially reduced their charges.

Sizing is *eXtremely* restrictive; ditch them.

Thanks; added PCBwig to the list. Prices are higher than PCBcart for quantity, but better for small quantities (eg: one).

You don't specify all manufacturing methods?

It was actually specified, but there's a limit to how much you can ask of overseas suppliers, and we supplied the components. Next time it will be done correctly.

Best regards, Spehro Pefhany

You get what you pay for.

Sure. Seldom more, often less.

Best regards, Spehro Pefhany

It should be automatic except if they're supposed to be unplated-- which takes an additonal operation.

Best regards, Spehro Pefhany

• Check; for small quantities (like i said) YouPCB beats everyone else. Do not need and cannot use 50 UNTESTED boards. "Tested": One cannot test a raw, un-populated board - ain't no continuity. In my case, the ONE is for mechanical checking/testing in a special environment.

I'm guessing traces: tested for continuity / against shorts.

Flying probe tester.

Irrelevant, unless they're really long.

More than one company has been kicked off the approved source lists for mucking with the process without approval. Maybe they'll learn.

Your supplier failed to sand the edges; that should be almost as automatic as plating thru holes (which also does not always happen).

Cheaply one uses a bed of nails fixture with pogo pins.

More expensively, but without significant NRE costs, one uses a "flying probe" tester. This is the choice for prototype quantities.

Both methods confirm the netlist (typically extracted from the Gerbers) for both continuity and shorts. Nobody wants to debug a complex prototype built on an untested board if they can reasonably avoid it. If there's only 20 or 50 low-pin-count parts on a 2-layer board, it's not so important.

OK, i will byte..HOW does one cheaply test a PCB with hundreds of un-connected traces for "continuity"? And where over 90 percent of them are in the 300 mil region?

The fact that they are "300 mil" is irrelevant, not the traces themselves.

They program a robot, from the gerbers, to whiz around with a "flying-probe" continuity tester looking for continuity and shorts. This typically has no setup costs but has an added unit cost, to pay for the robots time per board, so each board might e.g. cost an extra $0.50.

Or they make a bed-of-nails fixture which makes contact with each pad. The fixture might be a one-off cost of $300, but is instantaneous in operation so there is no added unit cost.

So for prototypes and low volume, use flying probe testing. For higher volume (hundreds+) use bed-of-nails.

Exact prices will depend on the board complexity and the supplier of course.

So yes bare boards can be tested for continuity (and shorts). They usually are AFAIK, the added cost is normally negligible compared to scrapping a populated board. IME it varies a bit with board type, testing is usually optional with 1- and 2-layer boards, mandatory or included with 4-layer and above.