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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

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.

ZenoArrow 11y ago
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?
- cillian64 11y ago
  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.
  - jwr 11y ago
    Just order them from OSHstencils. They aren't expensive.
  - ZenoArrow 11y ago
    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-stencil-out-soda-can http://www.popsci.com/article/diy/build-diy-soldering-stenci...
- jdietrich 11y ago
  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 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 https://www.oshstencils.com/pricing.php http://www.smtstencil.co.uk/ http://www.smtstencil.co.uk/
bhickey 11y ago
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.
- cillian64 11y ago
  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.
  - LeifCarrotson 11y ago
    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 https://www.sparkfun.com/products/10243
  - bhickey 11y ago
    Got any debugging tips? I had a lot of trouble with lead-free paste bridging on small pitch components.
- stephen_g 11y ago
  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).
vongomben 11y ago
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 http://www.seeedstudio.com/service/index.php?r=pcb
kersny 11y ago
You could check out Macrofab: https://macrofab.com/ 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.
- drone 11y ago
  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.

ZenoArrow 11y ago

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?

cillian64 11y ago
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.
- jwr 11y ago
  Just order them from OSHstencils. They aren't expensive.
- ZenoArrow 11y ago
  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-stencil-out-soda-can http://www.popsci.com/article/diy/build-diy-soldering-stenci...
jdietrich 11y ago
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 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 https://www.oshstencils.com/pricing.php http://www.smtstencil.co.uk/ http://www.smtstencil.co.uk/

bhickey 11y ago

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.

cillian64 11y ago
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.
- LeifCarrotson 11y ago
  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 https://www.sparkfun.com/products/10243
- bhickey 11y ago
  Got any debugging tips? I had a lot of trouble with lead-free paste bridging on small pitch components.
stephen_g 11y ago
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).

vongomben 11y ago

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

kersny 11y ago

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

drone 11y ago
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.