.pos File Component Rotation

I’ve just finished my first PCB for assembly with JLCPCB. In my excitement I missed the fact a component was rotated 180 degrees in their viewer. All other parts appear to have the correct rotation. The part is correctly shown in KiCad so something must have gone wrong in the exporting step.

Will JLCPCB notice and rotate the part for me? It’s a SOT-223 so is very noticeably wrong. Is there a way to change a part’s rotation for exporting a .pos file?


How do you know the pos file is “wrong”?
Maybe there is an error in the rotation of the 3D model itself.

And the chain starts with the orientation of the parts in the tape, I would not even trust that would be standardized.
I’ve even got some vague memory of a suffix to part numbers to specify different orientation of the parts in the tape.

Fixing stuff like this is one of the reasons setup costs are high.

You’ve got the luck that SOT-223 is very assymetrical, and it seems likely that they catch this error, but I would contact JLCPCB about this even before thinking about writing a post here.

I’m curios to read how this ends, so please post a update after it’s fixed.

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Please, just read JLCPCB BOM and Pick and Place. It is just a different standard used for the libraries, there is there a Python script to automatically convert it.

There is allow Python tools here in the forum to help with the BOM list of JLCPCB.

JLCPCB has assured me that they will fix any such issues…though I try not to trust them too much ;-). They twice rejected an order due to “a missing drill file”, even though the board did not have a single drill hole in it. (The first time, they canceled the order and issued a refund with a note saying why. Second time they put the order on hold and sent me an email asking for clarification.) So far, I have been very happy with their service, whether customer or otherwise.

I don’t know what’s wrong, but thus far for me, KiCAD POS files have the following rotation errors (from JLCPCB’s perspective):

  • SSOP-28: rotated -90 (probably all SSOP)
  • HTSOP-8-1EP: don’t recall what, but probably -90.
  • SOIC-14: ditto (probably all SOIC)
  • SOT-23: rotated 180 (good luck catching THAT with a SOT-23-6)

For whatever reason, SOT-363 (SC-70-6) is correctly oriented. I don’t know where this problem is, whether it’s JLCPCB or KiCAD being inconsistent.

EDIT: Responded before checking the link in the above post…that explains it very concisely. Cheers, so much for standards…

:thinking: IMO it would have been simpler to generate and send them the empty drill file. This satisfies their workflow and is more effective communication than a note saying, look for yourself there are no holes in my order.

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Second time I did include the empty drill file…and they asked me if the file was corrupted.

EDIT: Here’s the email I received the 2nd time:

Hi Dear,

Thanks for your PCB order in advance .

ambiguous missed drill layer - based on your Gerber file, the drill was missing, can you advise if correct to proceed as your file OR need to place new order as SMT order does not support updated file to replace yet.

Thank you.

I suppose it demonstrates the checks are working.

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I’ve sent them an email and they said they’d be able to rotate them if it wasn’t caught in their review stage.

Surely there’s got to be a better way than visually checking if everything looks good in their viewer? I looked through pretty thoroughly after I noticed the first part but checking again now I found another part rotated 180°.

KiCads official library uses IPC-7351x (x = A, B or no suffix) zero orientation A. This means pin 1 (or A1) is always at the top left corner (if applicable).
This information should be all any assembly house ever requires as they know the orientation of the part in the tape, the orientation of the board relative to the assembly machine as well as the feed direction (you do not really know most of these as a lot of components come in multiple tape configurations and it will depend on which exact one the assembly house has at hand)

If you added footprints from any other source (downloaded from the net or designed them yourself) then they might not follow this rule which would complicate matters a bit.

And why can there be problems? Well there sadly is more than one standard for zero orientation (Even IPC has an alternative where pin 1 is on the bottom left, some other standards have differing orientation for ever type of package, …)
Additionally the orientation within the tape is not standardized at all (normally this is however handled by the assembly house, could however be that low volume producers push this task to their customers as it might otherwise be too expensive)

It seems they have a very good review process. They picked up both parts which needed rotating and rotated them to match the silkscreen. I’ll let you know how it goes when I get the finished board.

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