JLC PCB - reorientation of octagonal pads

[home_listening]

Hi,

Just wondering if anyone else has experienced this with JLC PCB,  the rotation of octagonal pads has been adjusted by 22.5deg. Its fairly clear next to the clearance in the copper pour of this board. Not a big issue on this order as its a mounting point for heatsinking, but for closer tolerance designs it could be a major problem. I've emailed them about it.



Cheers -HL

[Mangozac]

The image won't load for me, but I'm curious the reason for selecting octagonal pads over round?

[Eunice Yin]

@home_listening

I don't think this is a problem of them, maybe the problem of your Gerber file generation software.

[JLCPCB Official]

@home_listening

Dear Sir,

This is JLCPCB support, we are very sorry that there is a problem with your order.
Generally we can't any modification with customer's design without the permission of customers. And if there is any design modification requirement, we will ask our customer to modify it by themselves in case there is any misunderstanding.
Regarding your problem, We can not help to check out where the problem is, since We don't know your order number. Could you pls send email support@jlcpcb.com or submit a complaint on JLCPCB account, they will solve the issue soon.
If it is our problem and you can not use the board, we will refund or remake the board for you, so please don't worry, haha  .
We consulted our engineer, they said there maybe a bug when you generate the Gerber file.
Any question,just feel free to contact with us

[home_listening]

My $0.02 is CAM postprocessor setup issue. In some CAD software, you can specify how geometries are defined in Gerber files. For instance, for a circle, you can specify it as a circle and expect the CAM importer to interpolate that into a circle, or you can specify it to render the circle into multiple vectors.

The former gives you best accuracy, but a bug in the receiving end's proprocessor could ruin the result. The latter is WYSIWYG, but you have limited resolution or potentially a very large file.

For a circle it kinds doesn't matter as it doesn't have an orientation, but for an octagon, there is.

Yeah, I did the PCB in eagle and checked it in the Kicad Gerber viewer and then the JLC websites gerber viewer - all of these show the correct orientation. So it happened somewhere down the line.

[home_listening]

The image won't load for me, but I'm curious the reason for selecting octagonal pads over round?

I suppose I could argue that the geometry of the octagon offers slightly greater surface area on the pad compared to a circle, but to be honest I just like the look of a bunch of 45degree traces next to the 45degree angles of the pads.

[home_listening]

@home_listening

I don't think this is a problem of them, maybe the problem of your Gerber file generation software.

The pads are the correct orientation in my software, when viewing the gerbers in Kicad's gerber viewer as well as the JLC website gerber viewer. Since you are clearly a bot, perhaps stick to more honest tasks like trolling Justin Biebers twitter account?

[home_listening]

@home_listening

Dear Sir,

This is JLCPCB support, we are very sorry that there is a problem with your order.
Generally we can't any modification with customer's design without the permission of customers. And if there is any design modification requirement, we will ask our customer to modify it by themselves in case there is any misunderstanding.
Regarding your problem, We can not help to check out where the problem is, since We don't know your order number. Could you pls send email support@jlcpcb.com or submit a complaint on JLCPCB account, they will solve the issue soon.
If it is our problem and you can not use the board, we will refund or remake the board for you, so please don't worry, haha  .
We consulted our engineer, they said there maybe a bug when you generate the Gerber file.
Any question,just feel free to contact with us

I appreciate the response, This isn't a big problem for me on this project - I didn't even notice until today (a month or so after I got the boards) and everything built so far has been fine. I reported the bug through the website today so it should show up for you.

Cheers.

[xavier60]

PCBWay can do octagonal pads correctly from my Protel 98 PCB files.
 They have to be reminded to check otherwise there is a chance of the octagonal pads being converted back to round at production time.
I have never been able to produce my own Gerber files with the octagonal pads showing correctly. They either get converted back to round or are rotated by 22.5°.
I got a reply from JLCPCB saying "Gerber only"

[phil from seattle]

Interesting, they appear to still be doing it. Or I should say, doing something similar.  I hadn't noticed until I read this (old) post and looked at my recent boards from them.  I'm trying to attach a photo of it but not seeing it on the preview.  If it shows up, you can see that they have rotated the octagonal pads by almost 45 degrees. They didn't change the copper around the pads so you can see what I originally intended.  I also tried to attach a image of the board design to show what I wanted.  Pretty sure my DRC would hurl lunch over the rotation because it's less than 6 mil clearance.  I've had several boards from them and they seem to work fine. Maybe I should switch to round pads.  Eagle 7.7

[xavier60]

Interesting, they appear to still be doing it. Or I should say, doing something similar.  I hadn't noticed until I read this (old) post and looked at my recent boards from them.  I'm trying to attach a photo of it but not seeing it on the preview.  If it shows up, you can see that they have rotated the octagonal pads by almost 45 degrees. They didn't change the copper around the pads so you can see what I originally intended.  I also tried to attach a image of the board design to show what I wanted.  Pretty sure my DRC would hurl lunch over the rotation because it's less than 6 mil clearance.  I've had several boards from them and they seem to work fine. Maybe I should switch to round pads.  Eagle 7.7

Is the problem visible  when your Gerber files are viewed?

[phil from seattle]

Good question.  No, they appear to have the correct orientation.  Though, the JLCPCB gerber view isn't very clear so I have been relying on other gerber viewers.  I haven't had any other issues with them. [edit: all other viewers show the correct orientation]

I've had 3 PCBs made by them and all of them have the same issue. Though, the first two have been fully validated with no errors (design or fab) and I am in the process of validating the third - it looks very solid as well. Other than the issue being discussed. I've attached a screen shot of approximately the same area from their website.  A little hard to make out but the pad orientation looks correct.

[JLCPCB Official]

Good question.  No, they appear to have the correct orientation.  Though, the JLCPCB gerber view isn't very clear so I have been relying on other gerber viewers.  I haven't had any other issues with them. [edit: all other viewers show the correct orientation]

I've had 3 PCBs made by them and all of them have the same issue. Though, the first two have been fully validated with no errors (design or fab) and I am in the process of validating the third - it looks very solid as well. Other than the issue being discussed. I've attached a screen shot of approximately the same area from their website.  A little hard to make out but the pad orientation looks correct.

hello sir, do you mean by our Gerber view is not good?any suggestions for our " JLCPCB Gerber view "

[phil from seattle]

Thank you for replying.  The gerber shown is small and the gerber viewer is clumsy to use (zoom interface in a small window).

Note that for the purposes of the above discussion, there wasn't an easy way for me to get to the view for the project that had been completed. 

I just went and uploaded my old project and used the gerber viewer to check the project I submitted (the one with the rotation issue) and the JLCPCB viewer shows the octagonal pads as properly oriented while the PCBs I received have them rotated by about 40 degrees. While I continue to be a customer of JLCPCB, I am concerned that the board was not what I had expected.  I have changed to use round via's and pads to better work with your processes but wonder why this happens. Other vendors do not have this issue.

[JLCPCB Official]

hello ;

Good that you have Emailed the issue to the technical team first, in the EDA you are using you can manually set the component orientation by rotating it through a customized rotation angle so no need for the automatic rotation since it depends on each components.

[phil from seattle]

... in the EDA you are using you can manually set the component orientation by rotating it through a customized rotation angle so no need for the automatic rotation since it depends on each components.

Yes, true for components but there is no way to change pad or via orientation - they are not components.

[oPossum]

Octagonal pads can be rotated in Eagle in the library editor but this should not be necessary. I have had 3 PCB designs done in Eagle 7.7 made by JLC and they all had the correct pad rotation. A picture of one is attached.

[phil from seattle]

Sure, but there is no way to do it through their interface.  And, frankly, it would be a terrible service if I had to redesign a part each time I try to get a board made - the rotations do not seem to be consistent from job to job.  And finally, their gerber viewer doesn't show the way it will look when manufactured so there is no way to know the rotation needed, a priori.

[edit] and in Eagle, there is no way to rotate a via, square or octagonal. [/edit]

[xavier60]

Futurlec used to send me a PDF file showing exactly what the layers were going to be like for my approval before production.
I often had to point out the presence of octagonal pads. They would always eventually get it right.

[oPossum]

My previous three JLC orders all had correctly rotated octagonal pads, so I ordered eighteen different PCBs designs a few weeks ago. All of them have at least a few octagonal pads. They arrived a few days ago and results where not as expected. Eight have the correct rotation and the other ten are incorrect. Several of these used the same library part (40 pin 0.1 header) and began as the same schematic/PCB template. I thought the Eagle CAM file may have been the cause of rotated pads but this is clearly not what is happening. Something is very wrong with the CAM processing at JLC. Here is a link to a picture showing a PCB from ~6 months ago that is correct (top), and 7 from the recent order with only one correct (2nd from top): http://compendiumarcana.com/forumpics/jlc_oct.jpg

There may also be some drill size and/or pad size problems (not shown in that pic). I haven't measured that yet, but it doesn't look right.

[xavier60]

It's a very puzzling problem.
 If I generate my own Gerbers from Protel 98, I see some 22.5° rotated octagonal pads when I check with a  viewer.

[phil from seattle]

Yeah, it's a bit of a mystery. I simply stopped using octagonal pads for JLCPCB boards.  I'm a little dissatisfied over it - I prefer octagonal because they make it easy to avoid acid traps. But, for the cheap service, I'll live with it.

[JLCPCB Official]

Hi,

Just wondering if anyone else has experienced this with JLC PCB,  the rotation of octagonal pads has been adjusted by 22.5deg. It's fairly clear next to the clearance in the copper pour of this board. Not a big issue on this order as its a mounting point for heatsinking, but for closer tolerance designs it could be a major problem. I've emailed them about it.

Hi. Sir
Software compatibility problems causing this angle to shift. We received feedback and have improved this kind of octagonal pad problem, which has greatly reduced the occurrence of similar situations.  You should receive a reply email as soon as possible and hope you get a satisfactory reply. thank you!

[IconicPCB]

I seem to recal the old Protel software had this kind of feature.

Some pads would not translate well from Gerber to photo tool.

Altium has not had this problem to the best of my knowledge.

Just to round off... The problem is not necessarily with JLCPCB CAM software, it is more likely to be with individual clients Gerber exports.

[Lukas]

Try opening your gerbers in CAM350 (demo version works) since that's what they use at JLCPCB. That wouldn't be the first time that CAM350 misinterprets the gerber spec: https://blog.horizon-eda.org/misc/2019/11/18/gerber.html