Dangerous Prototypes Open Source Hardware

Assembly

July 22, 2016, 09:13:43 am

I have had a couple of different PCBs made and am suitably impressed but I wonder if there are any associated facilities that will assemble them for me?

That way I could just send the PCB and have it forwarded to someone local to where the PCBs are made with the schematic and have the things built then shipped to me completed.

Re: Assembly

Reply #1 – July 22, 2016, 09:20:13 am

Both iTead and Seeedstudio offer assembly services.

Re: Assembly

Reply #2 – July 25, 2016, 08:44:49 am

But are they associated with DirtyPCBs. I have used other companies for doing this but figure that as this one offers such a good service for small numbers I would rather put my money into it than other non associated companies.

I find it really hard to tie products and services to companies in China because I don't understand Chinese and all the addresses look the same. Last time I was in Shenzen I couldn't believe how hard it was just to get from one place to another even in a taxi they took you anywhere except where you wanted to go. :)

Re: Assembly

Reply #3 – July 25, 2016, 08:58:10 am

Seeedstudio does Dangerous Prototype's production, assembly and fulfillment, and as DirtyPCBs is DP I guess you could say they were "associated".

Re: Assembly

Reply #4 – July 29, 2016, 07:44:50 am

We will be doing 100+ starting in a few day, just as part of an "experiment" to tackle a certain problem I see in the open hardware manufacturing pipeline though. We have no real plans to do any hardware assembly.

I personally don't see myself ever touching the prototype assembly problem (1-99 units). I don't see how to build a sustainable system to do it (like DirtyPCBs) and it hasn't sparked my interest.

I also highly doubt there is money to be made in hand assembling 2-10 units for someone. If you send us all the parts I can get someone to hand solder them for $200-500/board, which is a great price for a big company, but from what I've seen hobbyists want to pay $20 and have all the parts sourced for them too.

Re: Assembly

Reply #5 – July 29, 2016, 08:01:06 am

I would point you to Seeed's service too. If you use their part library then they can hand assemble a board for you in low quantity. They try to solve the low volume problem by restricting the part selection though, so it is very restrictive.

Re: Assembly

Reply #6 – July 29, 2016, 12:44:20 pm

I just ordered my first prototype including assembly from Seeedstudio. The process is quick and relatively painless, provided you plan for it from scratch.

Here a short rundown of the process:

1) Design the circuit with components in their library. The library is quite complete. They provide complete Eagle libraries, as I'm using Eagle anyway, this was good for me and painless.
2) After the design and layout is completed and checked (using the provided Eagle ERC configuration) create the gerbers (using the provided Eagle CAM script to make them) and zip everything up in a zip file.
3) Create a csv files with the BOM. They need a CSV with all components, referring to the component by its Seeed SKU. This is a manual process.
4) Order the prototype on the Seed website, providing the zipped gerbers and the BOM csv. You will get a precise cost estimate with the PCB, Parts, Labor and setup fee separately listed. See my example here: http://imgur.com/4QBSGKB

In my case the PCB was $10, the setup fee $25, the parts $2.50 and assembly $7 per PCB. For single prototypes the $25 setup fee can be a setback.

My sample device essentially is a USB/serial converter (to program ESP8266/8285 devices). Similar to what goes for $3 on Ebay, so the small quantity makes stuff expensive. But $13 for 10 or $45 for one piece is actually not that bad.

Re: Assembly

Reply #7 – August 01, 2016, 11:34:45 am

I guess it will be handsoldered?

I'm curious for the result.

Re: Assembly

Reply #8 – August 01, 2016, 04:21:44 pm

[quote author="Sjaak"]I guess it will be handsoldered?

I'm curious for the result.[/quote]

I suspect so. This is the first time I do that, so I'm curious too. :-).

On one of the PCB's I'll have to add the chips they don't have myself, too.
It is an ESP8285 in a 32pin 5mm by 5mm housing, I'm planning to use my hot air gun for this.

Re: Assembly

Reply #9 – August 08, 2016, 01:12:04 pm

Just an update: Got a mail from Seeed today about two problems:

1) The BOM names two LEDS as 'D1', and 'D2', but the lapels on the silkscreen read 'Pwr' and 'Tx', so they don't know which is which.

2) I changed a 10uF cap from ceramic to tantalum late in the design process, but forgot to change the footprint. Tantalums seem to have special footprints, not the standard 0603.

So they have caught two errors of mine, which is a good sign about the quality of their work. (And not so good for mine :-) )

Re: Assembly

Reply #10 – August 08, 2016, 04:50:08 pm

thanks for the update.

Do they test also the board? Or just a physical inspection whether solderjoints are ok and all the components are in place?

Re: Assembly

Reply #11 – August 08, 2016, 09:50:07 pm

I did not supply a test plan, so they can not test mine right now.

I suspect I could have sent them instructions like 'plug into PC and verifiy that the USB/serial converter enumerates'.
But as this is my first circuit like this and the first time I let them assemble, there is a huge probability that any problem is with my circuit. If (huge if) there will be a small production run, then I'll have to create a test plan (and maybe a test software to be run on a PC).

Re: Assembly

Reply #12 – August 09, 2016, 10:23:25 am

Cool, thanks for the update.

Re: Assembly

Reply #13 – August 17, 2016, 07:30:00 pm

One more update: I got my package delivered by DHL today.

The order consists of two PCBs: One is a USB/serial controlled with the nodemcu reset circuit and a couple of LEDs on board, the other is a ESP8285 breakout board. The first board was built entirely from components in the OPL, the second board needs adding the ESP8285 and a 26 Mhz crystal. I have the components, but need to get around to solder them to the board now.

I did plug in the 1st boat into my PC, the CH340 enumerates and I can get the LEDs to blink. So far the board seems to work just fine, Yai !

For now I paid $150 for 3 assembled USB/serial boards, 7 bare USB/serial PCBs and 10 breakout boards with the Crystal and 8285 missing. I still might get a customs bill, up to $50, depending what fees get tacked on.

Re: Assembly

Reply #14 – August 21, 2016, 08:33:05 am

Thanks for the update, glad you had a good experience!