JLC PCB Prototype Assembly - Incredibly Cheap

[thinkfat]

This is from JLC website:

Rarely, the stock shown in JLCPCB website may be inconsistent with the actual stock, which may cause there is no enough stock for a component to process SMT assembly, then the component won’t be assembled on your boards. In this case, JLCPCB will refund you the cost of those unassembled components.

Anyone actually experienced this?

This may get quite ugly, if the not in stock component is actually important. For example, you have a board with 100 small 0402 capacitors, and few big 0805 ones. You can not solder 0402 by hand so you decide to pay for assembly. Since you do assembly anyway, why not to assemble 0805 as well? You order assembly, everything in stock, and then suddenly they say "sorry your caps not in stock, here is your board with your couple of 0805 soldered". Now you screwed up.

This is why I don't bother making designs that specifically target JLCs parts library. I let them mount all the passives from their basic parts library to save time. If I needed an actual small-batch production run I'd likely choose a different manufacturer.

[VEGETA]

Hello ;

JLCPCB support many PCB colors and could produce and assemble your PCB through the simplest ordering way, and also there is talented engineers that could guide you through to finish your order.
Find more here : https://jlcpcb.com/
Or just text me here for more details. 

Hello,

Your website states that assembly service requires only green solder mask to work.. so can i do it with black for example?

I want to produce around 100-200 boards of 50x50mm product, all parts are compatible with JLCPCB.com/parts and all of them are at one side of the board. I can panellize myself too if required.

What do you think?

regards!

sorry, we can't.Only green, up to 30pcs

If I have a board (panel) with dimensions of 280x280mm.. can I get 30 of it?

[thm_w]

For PCB manufacturing-related problems, I'm really sorry if our answer confuses you. This is a problem that we should not have. We will pay more attention in the future, and we will definitely give you a clear answer and guidance. Sorry again

Its alright, no confusion here, I can understand how hard it is to translate between languages. 

If I have a board (panel) with dimensions of 280x280mm.. can I get 30 of it?

You can try it on their site and see what happens: https://cart.jlcpcb.com/quote
I think the answer is yes.

edit: seems like they don't cap it to 30 but they would likely catch it somewhere later in the process.

[JLCPCB Official]

Hello ;

JLCPCB support many PCB colors and could produce and assemble your PCB through the simplest ordering way, and also there is talented engineers that could guide you through to finish your order.
Find more here : https://jlcpcb.com/
Or just text me here for more details. 

Hello,

Your website states that assembly service requires only green solder mask to work.. so can i do it with black for example?

I want to produce around 100-200 boards of 50x50mm product, all parts are compatible with JLCPCB.com/parts and all of them are at one side of the board. I can panellize myself too if required.

What do you think?

regards!

sorry, we can't.Only green, up to 30pcs

If I have a board (panel) with dimensions of 280x280mm.. can I get 30 of it?

Yes.You can get. When you panel board is ready, choose quantity:30).
More Detail here:https://jlcpcb.com//quote/pcbOrderFaq/PCB%20Quantity?_ga=2.180465319.1069198988.1592185484-2060532798.1551508394
Then notice the dimensions

Answer clear?

[Miti]

I’m sorry, I didn’t read through all the pages, I apologize if the answer to my question is hidden somewhere in this thread. My question is, can I use any CAD SW (Kicad, Eagle, etc) with my own libraries and then just edit the BOM, or do I have to use their libraries which I understand only exists for EASY EDA and Altium?

[langwadt]

I’m sorry, I didn’t read through all the pages, I apologize if the answer to my question is hidden somewhere in this thread. My question is, can I use any CAD SW (Kicad, Eagle, etc) with my own libraries and then just edit the BOM, or do I have to use their libraries which I understand only exists for EASY EDA and Altium?

you can use any CAD, but you'll have to make a BOM file and a placement file in the right format

There are scripts for kicad that'll generate the bom file and plament file, all you have to do is add the LCSC partnumber to the symbols

[phil from seattle]

I’m sorry, I didn’t read through all the pages, I apologize if the answer to my question is hidden somewhere in this thread. My question is, can I use any CAD SW (Kicad, Eagle, etc) with my own libraries and then just edit the BOM, or do I have to use their libraries which I understand only exists for EASY EDA and Altium?

what langwadt said. Also, be careful about your footprints if you make them yourself. And, verify ones that you get from somewhere else (especially with Eagle, lots of bad footprints out there, I don't know if Kicad suffers from that too). Make sure the origin is consistent with the datasheet as that is the pick and place target point. Make sure the pads are correctly aligned and the right size. Also, on the BOM, make sure that the LCSC part has the same footprint. There are multiple versions of some parts with different footprints in their library.

don't worry about rotation of the part in your footprint.

and by the way, with "jelly bean logic parts", different manufacturers each have slightly different recommended footprints. You'll have to decide which one you want to use.  For the most part, any of the footprints for a given part will work ok but worth understanding the difference.  An annoyance is that they use different names for essentially the same footprint so sometimes you have to go and compare the two footprints.  This turned out to be necessary for my last job because the TI 74LVC1G32 I selected was out of stock but they had one from NXP in stock.  Had to look at the footprints to make sure - different package names. Footprints were slightly different but close enough that it was OK.

[MarkR42]

The default "zero" rotation of the parts in the Kicad library and the JLCPCB parts library, is not always the same.

There are various fixes out there, to generate the pick-n-place file with the correct orientation. I am using a variation on essele's kicad jlcpcba plugin. However,

JLCPCB assembly has an *excellent* tool to check the parts orientation - it shows you the pcb, with the parts outlines and pins, and has pin1 super-clearly marked on chips, and A big + and - on diodes (and presumably polarised capacitors, I don't use any) - it shows you your own board with your own silkscreen, so it's usually super-easy to see any problems.

Also I think someone at JLC manually checks them, at least briefly, for correctness and would probably flag any obvious errors - but only if your silkscreen makes it clear to them.

[JLCPCB Official]

The default "zero" rotation of the parts in the Kicad library and the JLCPCB parts library, is not always the same.

There are various fixes out there, to generate the pick-n-place file with the correct orientation. I am using a variation on essele's kicad jlcpcba plugin. However,

JLCPCB assembly has an *excellent* tool to check the parts orientation - it shows you the pcb, with the parts outlines and pins, and has pin1 super-clearly marked on chips, and A big + and - on diodes (and presumably polarised capacitors, I don't use any) - it shows you your own board with your own silkscreen, so it's usually super-easy to see any problems.

Also I think someone at JLC manually checks them, at least briefly, for correctness and would probably flag any obvious errors - but only if your silkscreen makes it clear to them.

You are right
our engineers  will check the "+ -",  customers need to pay attention to correct DFM

[danie1]

I just had a batch of boards from the SMT service and found a strange defect. The one board I picked out to test didn't work at all and just when I was thinking I'd messed up the layout I noticed some unsoldered pins on the dc-dc regulator.

I tried soldering them but they seemed impossible to solder. Upon closer inspection the pads on the bottom didn't seem to have any visible pad under the legs so I removed the chip.

Something has gone very wrong with the solder mask but only on this one board and this one footprint. You can see the top right 3 pins pads are smaller than they should be, the center pad is smaller and the bottom right pins are completely covered. The nearby pads of other footprints are absolutely fine (closest is ~ 0.5mm from the upper right pad).

I'm glad it's just one board out of the batch but also, shouldn't this have been picked up by automated testing? I assumed there was automated optical checking that would notice missing pads. I know flying probe tests can check for continuity between pads that should be connected but I'm not sure exactly what JLC do as part of the probe test.

I've fired off an email to support and will report back what they say but thought it was an interesting enough defect to share.

I also had my first tombstones on this batch - I've found two 0402 caps that have tombstoned and both have equal copper and tracks leading directly out of them so not sure the cause. The solder looks more gray and less shiny than usual... not sure if that's related.

[Mangozac]

We've been using JLC PCB quite prolifically for the past year (for both prototypes and production) and today found our first issue. After lots of headaches trying to get the prototype working I sound that the pads on one component had been screwed up and there was no connection to the through hole plating on either side! This was the second revision of this board and the first one was fine, so the issue certainly shouldn't be with my footprint. I can't see how it would be the gerber/drill files either though.

Fortunately this was just a prototype and not production!

[JLCPCB Official]

I just had a batch of boards from the SMT service and found a strange defect. The one board I picked out to test didn't work at all and just when I was thinking I'd messed up the layout I noticed some unsoldered pins on the dc-dc regulator.

I tried soldering them but they seemed impossible to solder. Upon closer inspection the pads on the bottom didn't seem to have any visible pad under the legs so I removed the chip.

Something has gone very wrong with the solder mask but only on this one board and this one footprint. You can see the top right 3 pins pads are smaller than they should be, the center pad is smaller and the bottom right pins are completely covered. The nearby pads of other footprints are absolutely fine (closest is ~ 0.5mm from the upper right pad).

I'm glad it's just one board out of the batch but also, shouldn't this have been picked up by automated testing? I assumed there was automated optical checking that would notice missing pads. I know flying probe tests can check for continuity between pads that should be connected but I'm not sure exactly what JLC do as part of the probe test.

I've fired off an email to support and will report back what they say but thought it was an interesting enough defect to share.

I also had my first tombstones on this batch - I've found two 0402 caps that have tombstoned and both have equal copper and tracks leading directly out of them so not sure the cause. The solder looks more gray and less shiny than usual... not sure if that's related.

Dear sir, could you send me your registered email torebecca@jlcpcb.com, let me check  your file carefully.

[JLCPCB Official]

We've been using JLC PCB quite prolifically for the past year (for both prototypes and production) and today found our first issue. After lots of headaches trying to get the prototype working I sound that the pads on one component had been screwed up and there was no connection to the through hole plating on either side! This was the second revision of this board and the first one was fine, so the issue certainly shouldn't be with my footprint. I can't see how it would be the gerber/drill files either though.

Fortunately this was just a prototype and not production!

Dear sir, please kindly make a complaint on our website, we will assist you and give you a better solution.

[Mangozac]

Dear sir, please kindly make a complaint on our website, we will assist you and give you a better solution.

Thanks, yes I have already submitted a QC complaint on the order. I just thought it was a curious one and wanted to share here.

[danie1]

Dear sir, could you send me your registered email torebecca@jlcpcb.com, let me check  your file carefully.

I've already contacted support and they've forwarded the details on to the QC department but I'll forward it on to you too. Thanks for taking a look.

[c64]

We've been using JLC PCB quite prolifically for the past year (for both prototypes and production) and today found our first issue. After lots of headaches trying to get the prototype working I sound that the pads on one component had been screwed up and there was no connection to the through hole plating on either side! This was the second revision of this board and the first one was fine, so the issue certainly shouldn't be with my footprint. I can't see how it would be the gerber/drill files either though.

Fortunately this was just a prototype and not production!

Very strange, can you show us how your gerber copper layer looks?

[c64]

Maybe they should have one more category of parts and call them "super basic", which are guaranteed to be in stock. Like 100n capacitors or 10K resistors 

A good idea, do you think Pre-order parts service can help? If we receive order in advance, we will know which kinds of parts you need most, and we will prepare as we can.

It probably would not help. Now it will happen if you think you have the parts, but in reality you don't (how I understand it, because at the moment I submit the order you say you have the parts and you already reserve them for me). Pre-order will not help

[JLCPCB Official]

Maybe they should have one more category of parts and call them "super basic", which are guaranteed to be in stock. Like 100n capacitors or 10K resistors 

A good idea, do you think Pre-order parts service can help? If we receive order in advance, we will know which kinds of parts you need most, and we will prepare as we can.

It probably would not help. Now it will happen if you think you have the parts, but in reality you don't (how I understand it, because at the moment I submit the order you say you have the parts and you already reserve them for me). Pre-order will not help

from the pre-order service, we will know better which kinds of parts you guys need, and we are going to expand the library, add more type. will it not be helpful?

[bitseeker]

It's great to see the level of activity from JLCPCB Official here. Good stuff.

[VEGETA]

One question: can I combine the shipment of JLCPCB and LCSC?

[langwadt]

One question: can I combine the shipment of JLCPCB and LCSC?

I seem to remember there was a note that you can't anymore, because the export declarations are different for pcbs and components

[Mangozac]

One question: can I combine the shipment of JLCPCB and LCSC?

I seem to remember there was a note that you can't anymore, because the export declarations are different for pcbs and components

Yes, I tried to do this last week, was presented with an alert about some kind of restriction and instead was offered a significant discount on the shipping.

[Mangozac]

We've been using JLC PCB quite prolifically for the past year (for both prototypes and production) and today found our first issue. After lots of headaches trying to get the prototype working I sound that the pads on one component had been screwed up and there was no connection to the through hole plating on either side! This was the second revision of this board and the first one was fine, so the issue certainly shouldn't be with my footprint. I can't see how it would be the gerber/drill files either though.

Fortunately this was just a prototype and not production!

Very strange, can you show us how your gerber copper layer looks?

Gerbers all look good. Here's the top copper.

[JLCPCB Official]

One question: can I combine the shipment of JLCPCB and LCSC?

Sorry, no. The two cannot be transported together. The PCB factory(JLCPCB) and the components factory(LCSC) are separate. And our 5 PCB factories also located in different provinces. So maybe your different order are produced in different places

[JLCPCB Official]

We've been using JLC PCB quite prolifically for the past year (for both prototypes and production) and today found our first issue. After lots of headaches trying to get the prototype working I sound that the pads on one component had been screwed up and there was no connection to the through hole plating on either side! This was the second revision of this board and the first one was fine, so the issue certainly shouldn't be with my footprint. I can't see how it would be the gerber/drill files either though.

Fortunately this was just a prototype and not production!

Very strange, can you show us how your gerber copper layer looks?

Gerbers all look good. Here's the top copper.

is the distance between the pad and the through hole not enough?