Solder mask change by board house - Page 1
Forum section: electronics / beginners

author: joeyjoejoe
author_rank: Frequent Contributor
timestamp: March 10, 2019, 02:07:22 am
content: I put in an order for 100 boards with and SMT stencil.I noticed they changed the pad shapes to circles on the capacitors and resistors (1206), but not the SOD323's. The stencil matches. Is this some sort of standard that they did? I did not submit this.The top and stencil is the new order (JLCPCB). The bottom is an original 50pcs order I did from PCBWAY.The gerber's I submitted definitely are not round pads. Their preview even shows it. But the 100pcs gets an engineer review - is this some sort of IPC standard or something? Should I open a complaint if not?

author: Mr.B
author_rank: Unknown
timestamp: March 10, 2019, 02:48:05 am
content: In your case I would complain and have them remake the boards for you.My story with JLCPCB…I have previously had all my boards made at SeeedStudio.This time round I was doing my first ever 4 layer board. Shopping around I found that JLCPCB had the best deal for my requirements.Searching the EEVBlog forum, there are mixed opinions about JLCPCB, however most are favourable.I ordered: Panelising service – 6 per panel. 10 panels, ENIG, 1mm thick. Paste stencil. DHL. US$62.Delivery was very quick and I was quite pleased.Upon closer inspection, they have changed the solder mask on just one pad.The strange thing is that it is not filled in, but consists of lines of solder mask.This error is not in my gerbers, JLCPCB changed it.The stencil is fine – as per my paste layer gerber.I have not complained as the mask is easy to remove prior to paste and I am only using them in hobbyist quantity. If I was producing this commercially I would definitely complain.

author: Dubbie
author_rank: Unknown
timestamp: March 10, 2019, 02:55:27 am
content: I have had JLCPCB ignore my paste layer and roll their own in the past. Now I submit my stencil orders separately and only include the paste layer. This seems to make them come out correctly.

author: KL27x
author_rank: Super Contributor
timestamp: March 10, 2019, 10:34:46 am
content: If it were me, I'd like to try it out, first. Maybe it works better, or maybe it cleans easier? Maybe you will like it so much you start doing circles all the time? Or maybe you won't notice any difference, at all. (The latter is my guess).*edit: oh, darn. I was focused on the stencil. Now I see the soldermask. That looks pretty awful.

author: windsmurf
author_rank: Frequent Contributor
timestamp: March 10, 2019, 10:56:24 am
content: Are they trying to reduce copper usage?

author: Dave
author_rank: Super Contributor
timestamp: March 10, 2019, 12:40:25 pm
content: To me it looks like some automated editing screwup. The 1206 mask openings look like the exact same size and shape as the diode pads.

author: joeyjoejoe
author_rank: Frequent Contributor
timestamp: March 10, 2019, 02:01:14 pm
content: Yeah so I was actually a bit enthused about the solder stencil, I thought hmm, maybe it'll be just the right amount of paste or something, maybe it's IPC related.But I only now just noticed the actual boards. This would make any hand touchups near impossible. You wouldn't have any filet on the edge of the resistor.I opened a quality complaint with JLCPCB, we'll see what they say. Even if they run another batch, the worst part will be shipping, and then figuring out (or giving up) on reclaiming the import fees from DHL for the original faulty shipment.(IPC-SM-782A has this pretty well covered)