Author Topic: Are none cheap china PCB manufactures worth it?  (Read 1425 times)

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Offline JacksterTopic starter

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Are none cheap china PCB manufactures worth it?
« on: November 20, 2019, 09:35:22 pm »
Hi all

I am doing another batch of my PCBs and I am looking at doing a decent amount (for me that is around 100).
Looking to move away from China and to European PCB manufactures.

They are around 2-3 times the price though (with standard green silk screen, add another 50 cents per board for other colours).

Is it worth it?

I have only had one bad experience with a China manufacturer and recently they said they can't do my boards in black silk screen but they can do them in green.
Apparently their black silk screen cant go between pads <0.35mm

Sure this has been asked before, I do apologise in advance.

Thanks!
Jack

Offline Jwillis

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Re: Are none cheap china PCB manufactures worth it?
« Reply #1 on: November 20, 2019, 09:58:04 pm »
Are we talking silk screen or mask . In the case of mask black colour has carbon and/or cobalt to make it black. Both are conductive hence any spacing between traces less than a certain amount can't reliably be masked black without the possibility of conduction between the traces.
« Last Edit: November 20, 2019, 10:07:12 pm by Jwillis »
 

Offline Yansi

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Re: Are none cheap china PCB manufactures worth it?
« Reply #2 on: November 20, 2019, 10:19:47 pm »
Are we talking silk screen or mask . In the case of mask black colour has carbon and/or cobalt to make it black. Both are conductive hence any spacing between traces less than a certain amount can't reliably be masked black without the possibility of conduction between the traces.

I find that very very implausible. Let alone any content of conductive dye. No way.  More likely about its physical properties like viscosity.

https://electronics.stackexchange.com/questions/388715/what-impact-if-any-does-the-solder-mask-color-have-on-the-electrical-and-mecha
 

Offline floobydust

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Re: Are none cheap china PCB manufactures worth it?
« Reply #3 on: November 20, 2019, 11:10:18 pm »
You have "one bad experience" and write off the entire nation? How cheap did you go?Did you follow DFM on your pcb design.
There are many pcb houses in Asia that are excellent.

Local pcb houses are more expensive and I find they are always terrible at one thing. Either they can't get drill sizes right, or the silkscreen is smeared or dust in the process causes shorts between traces, or they use the cheapest laminate. It's just as much of a gamble if you bring it home.

Compare solder mask datasheets, no significant differences between green and all the other colours, in all properties.
 

Offline rstofer

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Re: Are none cheap china PCB manufactures worth it?
« Reply #4 on: November 20, 2019, 11:26:40 pm »
Are we talking silk screen or mask . In the case of mask black colour has carbon and/or cobalt to make it black. Both are conductive hence any spacing between traces less than a certain amount can't reliably be masked black without the possibility of conduction between the traces.

I find that very very implausible. Let alone any content of conductive dye. No way.  More likely about its physical properties like viscosity.

https://electronics.stackexchange.com/questions/388715/what-impact-if-any-does-the-solder-mask-color-have-on-the-electrical-and-mecha

You may find in implausible but it appears to be true:

https://smtnet.com/index.cfm?fuseaction=search_submit&searchstring=black%20solder%20mask&collection=

 

Offline Yansi

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Re: Are none cheap china PCB manufactures worth it?
« Reply #5 on: November 20, 2019, 11:56:58 pm »
There are at least two types of black solder mask: Shiny and matte.  Which one of the two we are talking about?

And at what conductivity?  I can verify none of the two on any PCBs I have available is conductive, at all. Two probes less then 1mm apart measure >40Mohm (low voltage testing).

If there is some kind of special option, maybe, certainly not standard production.

Until I see a datasheet of a standard black soldermask ink with specified conductivity and declared as conductive, I call :bullshit: on this one.

Very few internet sources mention this and they seem to not be of the very reliable ones. Also mostly copy-pasting from each other.

 

Offline Ysjoelfir

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Re: Are none cheap china PCB manufactures worth it?
« Reply #6 on: November 21, 2019, 12:15:36 pm »
Is it worth it?

I have only had one bad experience with a China manufacturer and recently they said they can't do my boards in black silk screen but they can do them in green.
Apparently their black silk screen cant go between pads <0.35mm


I haven't had one "really" bad experience with the chinese PCB manufacturers, only minor inconveniences like silkscreen too flimsy (because i misinterpreted the specs) or those damn batch numbers they tend to print somewhere on your PCB without asking.
This is what I prefer to do:
IF i need something ASAP, I order directly from one of the PCB houses in Germany I have used previously and know they are good - namely Würth and IBR Ringler.
I also order from those two if I absolutely need the best quality I can get and/or need something special, like a certain material the chinese don't cover with their standard offers.
On most other cases I go to china, especially for high volume small size stuff, the local manufacturers just can't beat the price.
Attached is a sample from my last order... 1000 of them did cost me twice the postage... Can't beat that.
« Last Edit: November 21, 2019, 12:41:31 pm by Ysjoelfir »
Greetings, Kai \ Ysjoelfir
 

Offline JacksterTopic starter

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Re: Are none cheap china PCB manufactures worth it?
« Reply #7 on: November 22, 2019, 04:00:40 pm »
I'll rephrase my question.

Is there a quality difference between the cheap China boards compared to the European manufacturer's boards?
If so, does the price increase justify the nearly 2-2.5x price increase?


Offline Ysjoelfir

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Re: Are none cheap china PCB manufactures worth it?
« Reply #8 on: November 22, 2019, 06:16:36 pm »
Is there a quality difference between the cheap China boards compared to the European manufacturer's boards?
Yes.


If so, does the price increase justify the nearly 2-2.5x price increase?
In many cases, especially non critical or simple designs: no. For high precision stuff with really tight specs: yes.
Greetings, Kai \ Ysjoelfir
 


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