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I'm a young engineer and I just started at my second job. I was surprised to see that the PCBs have no silkscreen. I'm currently working on the redesign of a PCB currently on the field and I'm trying to push for the re-introduction of silkscreen on boards. Some of the responses I get are:

  • boards are cheaper without silkscreen
  • since there are so many 0402 components, the silkscreen won't be readable anyways
  • there are too many vias and placing of silkscreen would be very difficult
  • you can view where the components are on your PC

In my opinion, those are not valid responses, but I'd like to know if there are any other companies out there that have similar "practice". Some of the products we produce go from 1000/year to 20K per year. But no silkscreen makes it more difficult to debug/test prototypes and field returns.

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    \$\begingroup\$ Make the next round of prototypes with the silk screen. You'll see for yourself if it makes sense. These would be just prototypes, and the additional cost of the silk screen wouldn't be big. Just my $0.02 \$\endgroup\$ – Nick Alexeev Oct 26 '12 at 21:38
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    \$\begingroup\$ Even if you don't design in silkscreen, your vendor may add it anyway, to put their logo and/or fire safety markings. Even if they don't break out the cost, you know it has to be paid for somehow. \$\endgroup\$ – The Photon Oct 26 '12 at 21:51
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    \$\begingroup\$ Maybe your company regards silk screens the way some proprietary, closed-source software shops regard debug symbols in binary executables: strip it away to hinder reverse engineering. Still, how much does it help someone to know that some capacitor is C29? \$\endgroup\$ – Kaz Oct 26 '12 at 22:04
  • \$\begingroup\$ That's a good point Kaz, I've certainly never had to sand off the laser markings on an IC for a similar reason :) +1 \$\endgroup\$ – Some Hardware Guy Oct 26 '12 at 22:06
  • \$\begingroup\$ You can easily also make a selective choice on a component by component basis if the silkscreen reference designators will show or not. You can also make a judgement call at some component size threshold such that all below that size will not have silkscreen unless the component has room around it or is an "important" component. Yet another consideration is to skip reference designators on silkscreen for common components such as all 0.1uF caps and 10K resistors. \$\endgroup\$ – Michael Karas Oct 27 '12 at 15:54
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Well I've made 1 million units for a product and they all had silkscreen and we fought over the cost of a resistor so it's not that cost prohibitive. Yeah I guess there is a cost associated with that but it's not that much. Also when you need to do rework, or when at the end of the line they are repairing boards that didn't pass testing, you want to be able to say "yeah replace U1 and change R17 to 33 Ohms" without having to haul out the schematic and the layout. Sure some factories will have computers with your drawings out there, and some have dirt floors ;)

For 402 components or vias just move your silkscreen, I mean I have 201 components that are labeled properly it's a matter of taking the time to do it.

So in short I agree with you I always prefer silkscreen, the only time I don't do it is when I'm making something for a hobby for myself and I'm being really cheap. Even then I usually try to label the parts in copper. Not saying you should do that for a real board though.

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    \$\begingroup\$ Even then, silkscreen on a single layer (top layer) is usually free for special pricing deals on 2/4-layer boards and is inclusive to lower-priced proto options like OSH Park. Aside from layout issues or volume pricing issues (not being able to get a volume pricing discount, rather), it seems ludicrous to not have a silkscreen. :P \$\endgroup\$ – Toby Lawrence Oct 26 '12 at 22:17
  • \$\begingroup\$ I agree with everybody's comments. I tried talking to the senior engineers and my boss but they would start saying: "you are not going to get it". The decision was made a couple of years ago before I got here and since we have assembly drawings, they don't see the need for silkscreen. It'd be just more work for the layout guy and 2 cents more per board (sigh...) \$\endgroup\$ – AMG Nov 6 '12 at 22:40
  • \$\begingroup\$ Direct your senior engineers to this thread. :) \$\endgroup\$ – rdtsc May 24 '16 at 11:58
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In my opinion, you should always use silkscreen, as it makes servicing and repairing of device much easier - which is a good engineering practice in general. More specifically, speaking of argumens you mention:

  • Production cost - well, yes, boards are cheaper. A drawback as I wrote above is troubles when servicing and troubleshooting the final device as you (service engineer) are almost unable to find anything on the board.
  • 0402 components - actually I'm almost sure I have seen boards with 0402 components and readable, although not perfect silkscreen. So, not sure how valid this argument is.
  • Vias - correct me if I'm wrong, but I thought vias can be (and usually are) covered by solder mask which negates that argument.
  • You can view some equivalent of the silkscreen on your PC - well, yes, but as a counterargument I can say that you do not need PC when you have silkscreen.

I won't make a conclusion as it is gonna be too subjective, but here it is - I can provide some counteraguments for each of the argument mentioned. It is up to you (your boss, marketing team, whoever...) to decide whether you need it.

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    \$\begingroup\$ It's been almost 4 years since. I provided the same counterarguments, but it's not easy to produce change. The last argument was from the layout engineer saying that it would be extra work for him to make sure the silkscreen is placed correctly... I'm a designer now and at least I get silkscreen on my test boards and prototypes, but he turns them off for production. That way the other engineers won't ask for it. Sounds silly but it's a compromise... I think. \$\endgroup\$ – AMG May 19 '16 at 14:39
  • \$\begingroup\$ @AMG Sorry, didn't notice the date :D But that doesn't really affect the arguments. Speaking of what you say - I'd rather prefer the silkscreen to be available in production than on prototype, because when you work with prototype, you can debug/place component/whatever even without it, but for mass product.. see my first counterargument. \$\endgroup\$ – Alexey Malev May 19 '16 at 15:00
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There are cases where adding silkscreen doesn’t make much sense. I am currently using one of those cases.

A miniature single-board logic/computer OEM device that is 40x50mm. The components are so closely packed together that there simply is no space for a proper silkscreen. Besides, there are so many BGAs and blind vias that probing is almost impossible.

Note that this has nothing to do with reverse engineering (they supply all schematics and even PCB layer drawings for all the versions of the board). And these boards are intended to be incorporated into products and be probed by engineers.

Their solution? An accessible PDF of the silkscreen. It clearly shows the locations of components and is actually easier to see.

With our boards I normally find myself reaching for the microscope to be able to read it anyway (is that a 0 or a 6 over that via?)

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  • \$\begingroup\$ Most sensible companies would always assert that "assembly drawings are final", because silkscreen quality is variable from board to board. I'd argue that in super-high density designs silkscreen might actually cause manufacturing defects as a fault in the silkscreen might cause the optical tracking of the PnP machines to wander. I don't have any evidence for this but I think it is plausible. \$\endgroup\$ – Wossname Mar 27 '19 at 15:02
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If you are cost driven company (I´m sure all are) and silkscreen is use only internally (customer never use it) it should be not use like in mine. Reasons: - cost driven (depends on volumes in summary, not single variants or models) - good and readable documentation in PDF will allow you to follow single parts and test points, - important marking like datecode, product number, etc. could be made by opening solder mask on copper (separated island with no signal, or GND or any other).

At the end you and your company need to make best compromise and solution for your products.

Nice day!

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Albeit unusual, if you have higher voltage than you normally encounter, I would say 1 kV but your 230 V flyback may count and you are concerned about creepage over time, you may leave out the silkscreen for the entire board or just the area with high voltage. This is due to the PCB having a known CTI or Comparative Tracking Index but the silkscreen does not. In case your are builing an X-ray power supply.

Another reason you run into a board with no silkscreen could be due to manufacturing issues. If your fresh batch of PCBs are delivered just in time for the manufacturing and there is something wrong, say hairline cracks in the copper, you are in a very tight spot and I have personally seen where all the local PCB companies are called and the fastest one is selected, sent the Gerber files to and you skip the silk screen to save time. Not just any time but the precious rented slot in production that you are running out of.

But most probably someone designed it without silkscreen just to cut cost.

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