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Comment by LeifCarrotson | Hacker News Reader

Same here! But I think that is the point of the article. The best way to make a cheap PCB is to just buy one. And he's probably right.

There are definite advantages to etching a PCB at home - if you make a mistake that you only discover on assembly, you can make a new run in hours instead of weeks - but soldermask, small vias, and small features are much easier at a real plant. And you won't beat the prices.

He recommends http://dirtypcbs.com/, I personally have had a lot of success with https://oshpark.com/ - local support, you only need 3 boards (not 10) for prototypes, and they do 2-layer in 12 days for $5/sq inch and 4-layer in 2 weeks for $10/sq inch. Once you need a production run, take it to Gold Phoenix.

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Do you know any places that do assembly as well?

My soldering skills are approximately good enough to do 0.1 inch pitch pins about 90% of the time, which isn't really good enough for surface-mount, and most modern microprocessors don't come in anything else.

You don't need to have great soldering skills for surface mount components. The easiest way to solder surface mount is the "solder stencil + solder paste" method (for want of a better term). You create a solder stencil to match the pin layout, place it over the PCB pads, apply solder paste, place the component on top then melt the solder (if you'd be doing multiple batches it's easy enough to modify a toaster oven to do this).

Solder stencils are also easy enough to create, especially if you have access to a laser cutter.

Are there any hackerspaces near where you live?

What do you cut your stencils from? I've spent a lot of time mucking about with various plastics and never gotten particularly good results - 0.5mm pitch pads tend to start melting together into a mess. The good stuff is meant to be Mylar, AKA PET. I've bought plastic advertised as Mylar which has not been particularly good, and I suspect it may actually be PE rather than PET, as apparently the two are often confused.

Just order them from OSHstencils. They aren't expensive.

Depends on how much you want to spend. If you're on a tight budget, you could try this...

http://www.popsci.com/article/diy/build-diy-soldering-stenci...

Using an electric hotplate for reflow also works very well for prototypes. You just watch the board and judge the reflow point by eye.

https://www.sparkfun.com/tutorials/59

Cheap PET stencils are available from OSH Stencils and SMT Stencil. For small boards, it's not difficult to dispense solder paste by hand with a syringe. The application doesn't need to be precise if you're using a board with a solder mask - surface tension does the hard work for you.

https://www.oshstencils.com/pricing.php http://www.smtstencil.co.uk/

How do you feel about using a toaster oven? I've had some success using a DIY reflow oven and pick-n-place by hand. Haven't tried 0201's, but 0402 resistors and 5mm QFN packages go pretty well.

Just don't use lead free solder.

I think the hate for lead-free solder is either a bit much, or outdated. I've used nothing but lead-free for both hand-soldered PTH and toaster-oven-reflowed SMT and get reliably excellent results. This is with cheap solder, dodgy HASL PCBs and a consumer toaster oven.

I don't know about cheap solder - I have done rework on lead-free boards that required an absurd amount of heat - but I love working with Sparkfun's special blend of 96.35% Sn, 3.0% Ag, 0.5% Cu, 0.15% Sb (Antimony): https://www.sparkfun.com/products/10243

Got any debugging tips? I had a lot of trouble with lead-free paste bridging on small pitch components.

Just don't use crap solder, actually... There are some good lead free solders available on the market now. Nihon Superior SN100C, for example.

The biggest problem I see with hand soldering is people not using enough flux (get a no-clean flux pen, they're amazing) and then just blaming the solder when they can't get it to flow... Reflow will do similar if you let the flux dry out (keep it in the fridge - I often put it in a zip-lock bag to try and really keep moisture out also).

You should try Fusion PCBA service[1] from Seeed. You have to use theiir Eagle library and if you happen to use other components they'll manage to find themselves with no charge

[1] http://www.seeedstudio.com/service/index.php?r=pcb

You could check out Macrofab: https://macrofab.com/

I've never actually used them but their online tooling is impressive, they have reasonable prices for low quantity assembly, and they've manufactured and fulfilled a few kickstarter projects.

Hi there! I am the founder of MacroFab, and I'm happy to answer any questions. Quick summary though: we do US-based (in Houston, TX) assembly, we offer low-cost prototyping options along with production quantities all with real-time quoting down to the component level, build-box assembly, programming, testing, inventorying, and fulfillment. We have APIs to allow direct integration and we have a number of integration partners coming online this year.

Does anyone have any recommendations for a PCB fab in Europe? i.e. where I don't need to wait 4 weeks.

I've had PCBs from China take a little over a week, if you checkout http://pcbshopper.com/ you can specify the delivery time you want to pay for.

BoldPort (https://boldport.cratejoy.com/) recently had some excellent boards made up with European Circuits (http://www.european-circuits.co.uk/).

I wrote a bigger comment too but Ragworm do (pretty cheap) 2-week turnaround. Only 2-layer by default though, get in touch with them for more.

If you pay DirtyPCBs some more money for decent shipping you can get your board in about two weeks. A week for fab, a few days for shipping. $14 for the boards, $14 for the shipping. It's still very cheap for very good boards, and even cheaper if you can batch up a few projects and combine shipping.

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