Equipment needed to assemble detectors and USB microphones, and assembly process
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Word of warning - hotplates get HOT - more than 250˚C - they are DANGEROUS. BE CAREFUL. When the solder paste melts, flux fumes are given off. These are toxic, DO NOT BREATHE THEM IN. Work somewhere well-ventilated, and use an extraction fan with a carbon filter if possible. Just stay safe, OK? You do not want to set fire to the house / the dog / the kids.
Before anything else, download this PDF and read it. It's a presentation for people running a self-build workshop to give to attendees, it's for a slightly older version of the hardware but is still worth a read. And also watch the video on the right, it's me going through a complete build of a USB microphone in about 7 minutes. Pippyg takes about the same time, pipistrelle a little longer as the 10 LEDs and resistors plus the audio output circuit and touch circuit has more components to place. In terms of what you will need to do assembly of these devices, there is a bunch of common stuff, and over and above that you will need specific PCBs and a specific set of components. Here are the PCBWay projects from where you can order PCBs and solder paste stencils - https://www.pcbway.com/project/member/?bmbno=34AFFBAD-C27D-47 - and in the project descriptions there is a link to the DigiKey shopping list you need to buy. |
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Equipment list common to all builds
a) a hotplate to melt the solder paste. You can go for the cheap but a little scary route of a £6.99 (September 2024 price) hotplate from Amazon (https://www.amazon.co.uk/POHOVE-Heating-Soldering-Heating-Soldering-Laboratory/dp/B08XJGJN59/ref=sr_1_5) or you can go for the much easier to control, more reliable but more expensive route - about £85 (https://www.amazon.co.uk/dp/B0BYN75FPN?th=1)
The cheap hotplate requires care - it gets VERY hot very quickly, and that can lead to thermal stress and more importantly differential thermal strain between the resistors and capacitors and the solder paste - if the solder paste hardens too quickly before it melts and the components are not up to temperature, you will get tiny explosions and components - at about 250˚C - bring thrown around the room. Be careful. But for only £6.99 it will do the job - I have built around 100 devices using a cheap hotplate.
b) superglue, and a hot glue gun and glue sticks. Hot glue gun and sticks no more than £6 from a hobby / craft store, superglue maybe £3 from a supermarket - Tesco always have Loctite in stock.
c) a solder stencil frame. This is to hold the stencil steady, in position, while you squeegee the paste through the stencil onto the PCBs. The cheapest and best way is to build one, using the hardboard that PCBWay use to ship the stencil as a base, and the snap-off sections of the PCB. Superglue them down to the hardboard using a PCB as a guide.
d) lead-free solder paste. This is not in the DigiKey shopping lists as you don't want a tube of it with every purchase, so get it here : https://www.digikey.co.uk/en/products/detail/chip-quik-inc/NC191SNL50/11480385
\Note that is is WAY easier to build these things with Sn60/Pb40 (i.e leaded) paste, which melts at a lower temperature and has much better wetting properties. But is has lead in it. If you fancy it, try it, but seriously - lead is bad.
e) quality, small tweezers for picking up an placing components onto the solder paste
f) a digital multimeter - this for post-assembly debugging if your detectors don't work after assembly. Shop around, I got one at Aldi for £7.99 and it's GREAT.
g) an electronics soldering iron with a fine tip - this is not even needed for a USB microphone build, but it's always good to have a soldering iron around.
a) a hotplate to melt the solder paste. You can go for the cheap but a little scary route of a £6.99 (September 2024 price) hotplate from Amazon (https://www.amazon.co.uk/POHOVE-Heating-Soldering-Heating-Soldering-Laboratory/dp/B08XJGJN59/ref=sr_1_5) or you can go for the much easier to control, more reliable but more expensive route - about £85 (https://www.amazon.co.uk/dp/B0BYN75FPN?th=1)
The cheap hotplate requires care - it gets VERY hot very quickly, and that can lead to thermal stress and more importantly differential thermal strain between the resistors and capacitors and the solder paste - if the solder paste hardens too quickly before it melts and the components are not up to temperature, you will get tiny explosions and components - at about 250˚C - bring thrown around the room. Be careful. But for only £6.99 it will do the job - I have built around 100 devices using a cheap hotplate.
b) superglue, and a hot glue gun and glue sticks. Hot glue gun and sticks no more than £6 from a hobby / craft store, superglue maybe £3 from a supermarket - Tesco always have Loctite in stock.
c) a solder stencil frame. This is to hold the stencil steady, in position, while you squeegee the paste through the stencil onto the PCBs. The cheapest and best way is to build one, using the hardboard that PCBWay use to ship the stencil as a base, and the snap-off sections of the PCB. Superglue them down to the hardboard using a PCB as a guide.
d) lead-free solder paste. This is not in the DigiKey shopping lists as you don't want a tube of it with every purchase, so get it here : https://www.digikey.co.uk/en/products/detail/chip-quik-inc/NC191SNL50/11480385
\Note that is is WAY easier to build these things with Sn60/Pb40 (i.e leaded) paste, which melts at a lower temperature and has much better wetting properties. But is has lead in it. If you fancy it, try it, but seriously - lead is bad.
e) quality, small tweezers for picking up an placing components onto the solder paste
f) a digital multimeter - this for post-assembly debugging if your detectors don't work after assembly. Shop around, I got one at Aldi for £7.99 and it's GREAT.
g) an electronics soldering iron with a fine tip - this is not even needed for a USB microphone build, but it's always good to have a soldering iron around.