First Board made in KiCad -> Silkscreen Issues and a Circle

on U1 it looks as if you have a cicrle on silkscreen that will end up under the chip.

not good

annular rings:

typical normal vanilla via, drill = 0.25 , pad = 0.45
0.1mm surrounding the drill, thats typically the minimum for fabrication without going to extremes, just plain fabrication.

your shop was not top notch

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Ok maui, this is maybe be a stupid question, so don’t slap me. :fearful:

Do normal smd pads have an annular ring? annular.py sees a violation of 0.1 on a normal SMD pad at a QFN Footprint. It is not a TH-Pad. I am confused… :confused:

Pad 15 for example…

Then you found a bug :beetle: in my annular script … so don’t slap me. :fearful: :grinning:
I’m going to fix it :wink:

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it should be now fixed :wink:
annular checker release 1.5.1

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There was nothing wrong with his annular rings to start with, it’s just not a very well made board. The silkscreen issue, that could have been avoided.

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wrong or not wrong depends on what the Fab is accepting… so adjusting annular to avoid Fab rework is a good practice if someone doesn’t want to switch Fab…
Other Fabs offer annular check internally during the order phase…
referring to the data PTH 0.6mm, DR 0.4 doesn’t fit minimum requirement for 18um standard Cu @eurocircuits
http://www.eurocircuits.com/wp-content/uploads/pcb-design-guidelines/Classification-Image2.png

Wrong would be adjusting the drill position to compensate for annular ring size and nearly isolating a track from it’s pad as is the case here. However, I believe the drill offset in this case was completely unintentional.

It would be interesting to know if all of the boards were like that.

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the simple answer is asking the Fab

Most of the board looks like this one:

the worst one:

Too bad the worst one… Did they mark it as bad or not?
May I ask you this Fab name?

Only Ian from DirtyPCBs know the real name of the fab. I am not angry. In this case: You get what you pay for it. For Prototyping in my case it’s ok. I ordered a couple boards at dirtyPCBs and they are all ok. This batch is the first with this problem. Maui is right, the annular ring was to small. Waiting for the next batch with bigger annular ring and we will see.
I never thought about it with eagle. In this case i learned a lot and that’s truly ok for me :slight_smile:

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Thanks for the photos. Of the the two vias we can see on the second board you have two breakouts, and one very unreliable track to pad connection. I imagine the via near the “C4” text is also close to cutting the track off.

I also checked with one of the fabs I have used and for a .4 mm hole their standard service would require a .8 mm pad but .4/.6 is certainly available and may incur an extra charge, in fact they will do down to a 0.1 mm hole. The annular ring for .4/.6 is still twice the minimum required by IPC-2221.

But clearly this fab wasn’t up to the task.

They should at least give some warning prior to the manufacturing process that they are not able to produce a board. But as @Zh4ng said. You get what you pay for. (Checking boards before producing them costs money. Costumer service costs even more.)

Last time I checked the drill pos tolerance for DPCB was +/- 2 mil (0.0508 mm) and the diameter tolerance for PTHs +/- 3 mil (0.0762 mm).
Worst case you would be looking at 0.1 mm - 0.0889 mm there (still positive) as the remainder of the ring around the hole:

That being said… the drill hole pos tolerance for the board in your hand is worse than 0.0508 mm, if those holes are roughly 0.3 mm diameter (or thereabouts). The tolerance you got looks more like 0.15+ mm to me… 2 times over their own limit.

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Thanks for sharing this, I’ve learnt a bit. I also had similar problems with circles with my mob, but luckily in my case it was board outline and they couldn’t make it till it was fixed. So yes its 2 arc’s for all PCB’s to make circles from here on out.
I’ve had similar offset holes, but not nearly as bad as that from who I use. I’ve used pcbway, but they aren’t as cheap as DPCB, unless you are making 5 PCB’s and above. So great prototype PCB pricing from DPCB.
As a note when I spec the PCB as ENIG they turn out much better then HASL PCB’s tolerance wise for hole locations. So I guess its a new/old machine thing.
Cheers

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Or a different fab altogether…
Most aggregators we westerners use on the web arrange jobs with different board houses were they see fit.
Elecrow does the same (one of their fabs can doe circles in silkscreen, but botches the soldermask, the other can’t do circles in silkscreen… no idea how many they use).

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For those are interested in. Here is the second Batch of the PCB. For the first time i used pcbway.com. Much better drillings.

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Hi @Zh4ng
if you are using a development version of KiCAD, I reworked my annular script to be used through the Action Plugin Menu, with just the click of a button :smiley:


https://kicad-info.s3-us-west-2.amazonaws.com/optimized/2X/b/bfe71eb0d1c222ad1e6f51c876749e83c3c22394_1_632x500.gif

Maurice

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Cool. I am using a april nightly and test it tomorrow… You get feedback…

It works like a charm. i wish i could programm. Big thanks for this piece of software.

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