Assembler expectations? - Page 1
Forum section: electronics / general

author: Precisiontools
author_rank: Regular Contributor
timestamp: December 17, 2011, 10:24:23 am
content: When people here are looking for small to medium scale PCB assembly, what are their expectations for the service?Do you supply PCB & components?Do you expect PCB testing after assembly? i.e. power up and function test?What sort of failure rate do you expect & get?Does manual assembly of surface mount components bother you?Any other issues you might want to add?Cheers

author: Balaur
author_rank: Unknown
timestamp: December 17, 2011, 11:21:23 am
content: Hello,Just some comments from my work experience:- We use an assembler company that also manufactures the PCB- Sometimes, the PCB comes from them, sometimes from another PCB manufacturer. They are not bothered by this.- We have developed a very good working relation with them and we are able to get a very good and fast service (i.e. get the car, go to them, have a component replaced/soldered/desoldered/inspected and get back home within a couple of hours)- We provide critical components (i.e. hard to find, specific, expensive, etc) and they are able to supply most of the things that can be ordered through Farnell. They usually have a stock of common stuff: resistors, caps, connectors, etc at good prices.- The assembly is usually automated with some manual interventions where it makes sense- The only testing performed on the populated board is short-circuit testing between the power domains and ground, some visual inspection and so on. To be honest, any kind of functional testing is difficult to be performed on our boards and it cannot reasonably be expected from the assembler- We had our fair share of reasonably-sized issues and we have been able to work with them to successful completion, but there was no recurring trouble that was obvious. On the other side, we also have been responsible for a lot of small troubles and in the end it evens out.- I do believe that a good business & personal relation is the key for a smooth experience.Cheers,Dan

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 17, 2011, 02:48:11 pm
content: The answer to most of your points is whatever you, the customer, wants (and pays) them to do.This can be anything from you sending them everything and them sending back assembled boards, to you sending all the design info and them designing the final PCB, building test jigs, sourcing parts and PCBs, sending fully assembled, tested and packed products and handling repairs afterwards.Obviously different companies are geared up to different levels of service and volumes, and choosing the right one is the most important thing.

author: 8086
author_rank: Super Contributor
timestamp: December 18, 2011, 01:22:42 am
content: I recently started a short-run assembly business, I offer board manufacture (obviously I don't do this myself, but I organise it), assembly of SMT and through-hole components, and part sourcing.I doubt anyone would expect functional testing if they saw my low prices.I'll source components for a fee, or customers can send their components to me (and boards as well, if they like).#Of course, it all comes down to the individual requirements for each project.

author: JuKu
author_rank: Frequent Contributor
timestamp: December 18, 2011, 04:28:48 pm
content: -Do you supply PCB & components?For PCB and standard components (such as discretes, standard logic etc) the manufacturer has much better suppliers than I do, so they'll buy those. Sometimes I supply hard to get components that I've got as samples or bought myself.-Do you expect PCB testing after assembly? i.e. power up and function test?Only if separately agreed. A test fixture and test program is a sizable project in itself.-What sort of failure rate do you expect & get?Are you implying that is ok for a manufacturer to ruin a board with several hudred euros worth of components on it? ;-) circuit boards must be 100% electrically tested, and the manufacturer must know their job. Any error willcause a serious claim.-Does manual assembly of surface mount components bother you?Acceptable only in special circumstances and with prior approval. Of course, workmanship must be perfect (there are measurable standards for this). I'm paying for a quality job.

author: Precisiontools
author_rank: Regular Contributor
timestamp: December 18, 2011, 09:20:48 pm
content: Quote from: JuKu on December 18, 2011, 04:28:48 pmNo. Most of my customers have been ignorant of how electronics works. They have an idea, they pay for someone to design the circuit & PCB and then they just slap it in their product case, fire it up and it works so they can sell it. So the boards HAVE to be 100% tested before they leave me which I insist on anyway.What if you do know about electronics and you don't want to pay for the testing? Yes the assembler can do some simple tests after assembly, but what about full functionality of the circuit? Do you expect the assembler to have a dedicated test jig and test the FULL functionality of it before it gets shipped back to you?

author: JuKu
author_rank: Frequent Contributor
timestamp: December 19, 2011, 06:15:44 am
content: Quote from: Precisiontools on December 18, 2011, 09:20:48 pmOn full production, yes, and I expect to have paid for the test development. For prototypes, just build the boards, our engineers will test them and finish the development.

author: EEVblog
author_rank: Unknown
timestamp: February 02, 2012, 06:57:52 am
content: Quote from: Precisiontools on December 17, 2011, 10:24:23 amAssemble the boards, exactly per my instructions and sample, that's it.QuoteUsually. Otherwise it's basically a "turn-key" solution.QuoteNO.They usually have no idea what they are doing.I have on occasion built and set up full custom test stations at the assemblers premises and have them do the testing to full documented test procedure written by us.But usually, I've mostly done the testing in-house.QuoteDepends entirely on the board complexity. Zero percent is usually not obtainable, especially on the first run.Double digit failures would be panic stations. A percent or two can often be written off as normal.Sometimes 0.01% would not be nice.Depends...QuoteNot really.Dave.

author: ciccio
author_rank: Frequent Contributor
timestamp: February 02, 2012, 07:43:31 pm
content: I have small (usually 50 pcs) lots of boards assembled by an assembly house.Most of the times what they do is only assembly, soldering and visual inspection. I supply them with bare PC boards and all the components.For some products, the assembler, who has a stock of "popular" components, supplies most of the components (PCBs and some "special" components are supplied by us), with a small mark-up (10 - 30 %).My company's size does not justify hiring a PCB assembler and buying the equipment needed for a professional result.Our policy is to do all testing in-house. Last year we had a defect rate of about 1-2 % (when for some reasons we had to assembly the same boards in-house the defect rate was 5-10 % !!!!)For other customers who are not in electronics business (such as mechanical manufacturers) the same supplier can source all the components (including PCBs) and does the mechanical assembly, full functional testing and even calibration.Test jigs are always supplied by customers (or by the design house that designed the product) , with detailed testing procedures.As everything in the real word, all this has a price.