JLCPCB - Misaligned component - Page 1
Forum section: electronics / beginners

author: Tantalum
author_rank: Regular Contributor
timestamp: January 08, 2025, 12:56:20 pm
content: HelloI have an ESP32-S3-WROOM-1U on my PCB.I used the official footprint from the Espressif github.Unfortunately, when I render the 3D model of the PCB in Kicad or upload the PCB on JLCPCB, the ESP module est misaligned by half a pin length as you can see on the picture. (Well the pin header also but that's not an issue, it's a through hole component, they will figure it out)I have verified the footprint and it's perfectly symmetrical in other words I have the feeling that the problem comes from the 3D model of the component and not the footprint.Now, on JLCPCB there is a way to realign the component, but since I'm quiet sure it's the 3D model and not the footprint that has an error, I fear to correct an issue that finally does not exist in reality on the footprint, resulting in a wrong component soldering.What do you think?What should I do?Thanks

author: newbrain
author_rank: Super Contributor
timestamp: January 08, 2025, 01:32:15 pm
content: In Kicad, it's possible to scale, rotate and offset 3D models along the three axes, look in the 3D tab of the footprint properties.You might have to create (copy) a footprint, if it belongs to the preinstalled libraries, and you don't want to change them.

author: igendel
author_rank: Frequent Contributor
timestamp: January 08, 2025, 01:36:49 pm
content: Not long ago I had a similar misalignment issue in the JLCPCB preview (a USB C connector, pins ~1mm off their pads). I opened a chat with live support and the representative promised that their engineers will review everything and I'll be able to verify the result later. And indeed, later in the process I could see another preview where the issue was fixed. [Edit: yes, this is unrelated to 3D models, but at least the soldering during PCBA should be ok...]

author: Tantalum
author_rank: Regular Contributor
timestamp: January 08, 2025, 01:46:47 pm
content: Quote from: newbrain on January 08, 2025, 01:32:15 pmI have done that.It works locally on Kicad.But on JLCPCB it's still misaligned (which is normal because the 3D model isn't part of the production file).I fear that JLCPCB uses the same footprint library from Espressif, that would explain the faulty 3D rendering on their website.Quote from: igendel on January 08, 2025, 01:36:49 pmThat's a good news.I will do the same.Thank you

author: DashApple
author_rank: Contributor
timestamp: January 08, 2025, 02:49:02 pm
content: I've had a few SMD runs on JLC and I had asked about it too since some components would end up off center or miss rotated and I was told the 3D preview is more a initial reference before its reviewed.You'll get a DFM Analysis result pop up under your order once it has been reviewed and put into production ; this will be the official placement they will use in said production, You can also select the option to confirm placement, this way you can view and confirm it before they put the board into production.

author: kmm
author_rank: Regular Contributor
timestamp: January 10, 2025, 07:25:10 pm
content: I suspect the model origin doesn't match the footprint origin. This isn't a big deal since you can tweak the offset in the footprint definition, I have a couple SMT LED footprints that recycle the same model by scaling and offsetting since they're both just cuboids of different sizes. As far as I know in KiCad the models are just for visualization purposes and don't affect the fab outputs for assembly, that's all defined by the board and footprint setup, and models just another footprint parameter.I just did my first assembly order with JLC about a month ago and they were very good about confirming any questionable part placements, and you can leave a note in the comment box outlining your concerns, so I wouldn't worry too much. It was an easier process than I expected and my boards came out great.