JLCPCB -- top/bottom Gerber view confusion - Page 1
Forum section: electronics / general

author: 13hm13
author_rank: Frequent Contributor
timestamp: October 19, 2020, 10:47:54 am
content: I have tasked (and paid for) JLC to create a 2-layer PCB.Have a look at JLC Gerber view:TOP:BOTTOM:The orig. files were created in Eagle, but I followed JLC's web instructions here ...https://support.jlcpcb.com/article/43-how-to-export-eagle-pcb-to-gerber-files...and created my Gerber files. The TOP view is perfect for drilling holes. In the BOTTOM view, however, note the holes are 180 degrees mirrored.What will my delivered PCB look like?

author: wraper
author_rank: Unknown
timestamp: October 19, 2020, 10:52:42 am
content: Most likely your files have bottom copper and solder resist layers mirrored. They will probably fix it or notify you.

author: 13hm13
author_rank: Frequent Contributor
timestamp: October 19, 2020, 11:36:15 am
content: I contacted (email: support@jlcpcb.com) a "Celia Li" over in JLC customer service. She doesn't know WTF is going on. She asked if she wants me to cancel the order w/o reimbursement?I asked to communicate directly with a PCB engineer so he/she can clarify. No response.Really??? ... is that how they handle things at JLC?This is my first order with JLC. And first impressions are important for repeat business.Not impressed, JLC!!

author: digsys
author_rank: Unknown
timestamp: October 19, 2020, 12:48:10 pm
content: Never seen that before, and haven't had any issues with them, BUT they are going through a few temp staff and Ihavehad to explain simple things once or twice to them. They've always "fixed" it, no problem and admitted the uncertainty. I wouldn't be surprised if other pcb manufacturers, in fact most type of manufacturers, are all going through tricky times. In my case, I've used them long enough to trust them, and accept it. Up to you howyourespond. Just giving my opinion.I do doubt though, that it won't be picked up before manufacture. They have pretty good quality checkers.

author: 13hm13
author_rank: Frequent Contributor
timestamp: October 19, 2020, 02:00:36 pm
content: Another thing about JLC is that they highly suggest you pay first (before reviewing).So my shame on me for pre-trusting the salesman's advice.But the f-ckup shown above is massive. And I don't see it in Eagle on my end. Even if they (correctly) use drill holes on the TOP as theonly, definitive reference, I am worried about that BOTTOM trace layer. JLC Gerber view BOTTOM shows it okay, but my confidence level in Ms. Celia Li is pretty low. Maybe JLC is what Dave refers to as "Won Hung Lo". Or maybe:https://www.urbandictionary.com/define.php?term=Won%20Hung%20Lo

author: JackJones
author_rank: Regular Contributor
timestamp: October 19, 2020, 02:08:18 pm
content: Their Gerber viewer is pretty buggy. I haven't seen issues with holes myself, but the silkscreen has been very buggy pretty much always for me.If other Gerber viewers show it correctly, I'd expect it will be manufactured properly. I think it's just the Gerber viewer doing it's buggy things.

author: Quarlo Klobrigney
author_rank: Super Contributor
timestamp: October 19, 2020, 02:29:23 pm
content: What version of Eagle? I have edited a cam file to output filenames in a different file extension. I do not have to do the drill cam as it's all incorporated in one now. Would you be interested? Also try ZoZPCB viewer. It will show you everything before you make a mistake.

author: jduncan
author_rank: Regular Contributor
timestamp: October 19, 2020, 02:30:31 pm
content: They can't let you speak to a PCB engineer becausea) That engineer probably speaks only Chineseb) That engineer works for a different company (the actual factory, not the sales front JLCPCB.com)However, I've had thousands of boards made by them without any issue, they are generally communicative (sometimes overly so) when they notice a potential problem. It's very likely a problem with the gerber viewer only.

author: phil from seattle
author_rank: Super Contributor
timestamp: October 19, 2020, 03:47:08 pm
content: I've had JLCPCB make around 20 different boards for me. Their gerber viewer is quirky to say the least. But you probably emailed the wrong person. I'd contact file review, you can get the address from their support/customer support menu pull-down. But, the bottom line is, I think you will be fine.A suggestion. Upload the gerber zip to oshpark and see what they say. I have boards made with both and if oshpark likes the board, then so will jlcpcb. There are other viewers out there as well. Use them.

author: 13hm13
author_rank: Frequent Contributor
timestamp: October 19, 2020, 03:57:17 pm
content: Here is Ms. Li's (of JLC) reply. Note the image she provided is still WRONG AF ....and WTF about that no refund? !!!!!!===================================================================Hi _____,Thanks for your reply.All bottom layer will be mirrored by engineer when production, such as the below characters, when you design bottom silkscreen layer, all characters should be designed mirrored.Then after engineer mirror again, the characters will be positive.So, should I cancel the order Y1-32------ without refund? Then you can fix the Gerber file and replace file.Thanks and wait for your reply,.Thanks and best regards.https://d33v4339jhl8k0.cloudfront.net/users/359135.178690.pngCelia LiSkype: support@jlcpcb.comWeb: JLCPCB.COM <http://jlcpcb.com/>Email: celia@jlcpcb.com <mailto:%7B%user.email%25>============================

author: jduncan
author_rank: Regular Contributor
timestamp: October 19, 2020, 05:00:46 pm
content: Quote from: 13hm13 on October 19, 2020, 03:57:17 pmStop panicking. They are saying that you can halt production and upload a replacement gerber file if you want.

author: Quarlo Klobrigney
author_rank: Super Contributor
timestamp: October 19, 2020, 05:27:59 pm
content: You can lead a horse......But sometimes a rattlesnake either causes it to lose it's mind or it just goesSo much drama, so little time......

author: phil from seattle
author_rank: Super Contributor
timestamp: October 19, 2020, 08:24:38 pm
content: Relax. At this point you should just let it go through. Their techs will fix the most obvious errors (assuming there actually is one here) and this would fall into that category.For next time, review your gerbers before you send them off. Also, read JLCPCBs FAQs as they have quite a bit of information available about the process.

author: JLCPCB Official
author_rank: Regular Contributor
timestamp: October 21, 2020, 02:16:34 am
content: We feel very sorry for any inconvenience caused. For every order, our engineers will re-check the file while preparing the production data used to manufacture your PCB to avoid production issue. when they find any file issue, we will inform you timely.Gerber viewer is a tool for previewing file and detecting some simple issues before ordering, just for reference, but it's not the criterion for our engineers' checking file before production. We will keep working in improving this online tool. Any feedback for our service and customer support, feel free to email our management, they will try the best to optimize the service.Contact JLCPCB :https://support.jlcpcb.com/article/45-contact-jlcpcb

author: donlisms
author_rank: Frequent Contributor
timestamp: October 27, 2020, 11:19:21 am
content: I'm confused... Why would you want to drill holes from both the top and bottom? Don't the holes from the top kind of... go all the way through? And if there is only one hole layout in the data (which wouldn't be surprising, because, you know -- through), and that got re-used because some checkbox somewhere said to, it would look flipped, yes?In other words, how does it look if you uncheck the "drill" layer on the bottom?Just a curious programmer -- not a PCB expert!

author: Siwastaja
author_rank: Super Contributor
timestamp: October 27, 2020, 11:54:12 am
content: This is getting more confusing than it needs to be.The fact they have shown a screencap from the gerber viewer they use to evaluate the boards, showing the exact same issue as their online gerber viewer, proves the problem is in your gerber.Have you looked at your files using a gerber viewer software (such as gerbv)? If not, why not?Because there is indeed a simple, single drill file; holes are drilled through the board, this only leaves one possible suspect:your bottom layer images (bottom copper, bottom soldermask, bottom silk, bottom paste, etc.) are, for some reason, mirrored.All PCB fabs expect the images to be non-mirrored, i.e., what you would see if you could look through the board from top.Your Eagle output settings have some "mirror layer" option checkbox, or similar, turned on, while it shouldn't be. Such checkboxes are useful if you DIY your own boards (printing masks yourself; in which case you'd want to mirror thetoplayer to get the ink/toner closest to the board), but only add confusion when exporting files for fabs. Because fabs have had similar requirements fordecades, you could expect some "just create working manufacturing files" default button from the EDA tools, but nope.Instead of communicating back and forth, fix the problem, now look at the files using any gerber viewer (I'd recommend gerbv) to verify, and resend the files.

author: Quarlo Klobrigney
author_rank: Super Contributor
timestamp: October 27, 2020, 01:36:10 pm
content: Because he wants everybody to do the work for him. He never asked for help in learning how to use Eagle in exporting the gerbers. I'm sure many would have been more than happy to help.Here's my new goto gerber viewer. I suggest supporting the author. Make sure that your files are in a known extension such as Altium, Kicad, Eagle, and preferably JLC's recommended extension name format in order to utilize the auto load function.https://www.zofzpcb.com/Quote from: Siwastaja onTodayat 20:54:12

author: phil from seattle
author_rank: Super Contributor
timestamp: October 27, 2020, 07:39:52 pm
content: Quote from: Siwastaja on October 27, 2020, 11:54:12 amMost PCB houses point you to a CAM file for Eagle that works for them. Pretty easy. I use the SFE 2 and 4 layer ones which seem to work with all the major PCB houses.Most techs reviewing a customer order will fix the obvious errors (and a mirrored copper layer is usually pretty obvious).

author: Microdoser
author_rank: Frequent Contributor
timestamp: October 28, 2020, 09:27:03 pm
content: Can't say I have had this problem in particular but the last order I sent them had a paste layer from a previous version in the zip.I got an email asking me if I wanted to have a stencil made up with the paste layer or from the file(PCB). I let them know the paste layer was included by mistake and to use the file instead so they should now be (fingers crossed) be making the right stencil.I always regard the PCB company as a case where you light the touchpaper then everything happens quickly from then on.This is why I always upload the Gerber, then cancel the order and double check the uploaded file using their Gerber viewer. It has saved me a couple of times, for example once I had solder mask over all the pads on one of my chips, another time the paste mask expansion had been set wrongly and all the pads were connected to each other. I often find a couple of vias that I wanted tented when they were bare and vice versa.At that stage, it is simple to just delete that file, make some new gerbers, and re-upload.Once you say 'GO' and pay the money, they go and it is best to be sure everything is right before you do.

author: TIOUK
author_rank: Contributor
timestamp: October 28, 2020, 11:07:59 pm
content: As others have said you have mirror on a layer in the CAM checked.Use gerbv before you order so you can resolve issue before uploading.Microdoser is incorrect, once you press " 'Go' and pay", it's not all over you can put the job on hold anytime up until the boards are in production. However they can move into production quickly, but you saw the error after upload, so would have been able to put them on hold.You can view the gerbers as soon as you upload and before putting the PCB into the cart and going to checkout.I have done 15 orders this year for over a 1000 pcs (many 1000's of individual PCBs as they are usually in panels) with no issues.Be courteous, I'm sure they are trying to help and that their English is better than your Mandarin, although things are lost in translation.The CAM I use is attached V6, but works on at least V7 (if the file upload works) I can't remember if the layer names are as they list, but I've never had them request a change of name and all boards have been manufactured correctly. You might need to select different silk layers, I use 121 & 122.They know what they are doing, sometimes when I used a strange footprint or a paste aperture that doesn't match the copper footprint (as it works better for us), they pick it up and ask if it's supposed to be like that.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: November 02, 2020, 01:00:04 am
content: Quote from: 13hm13 on October 19, 2020, 02:00:36 pmOrder a trial of 5 boards, it will cost almost nothing. The people at JLCPCB are very good and well done. They are always responsive and friendly, and respond here in the forum. Don't forget about the time difference - they can't respond to you instantly.Don't jump to conclusions, don't panic, everything will be fine - they won't do anything stupid, their engineers check all the boards manually intelligently, not automatically before production starts. You will never regret working with them. Very friendly company.And it would be better to prepare such a simple PCB in their online environment EasyEDA and there would be no questions.