Specifying a V-cut/groove on a PCB. Manufacturing in China? - Page 1
Forum section: electronics / general

author: Yansi
author_rank: Super Contributor
timestamp: December 17, 2018, 09:03:56 pm
content: Hello,how am I supposed to specify a V-groove on a PCB in a manufacturing data (gerber files)?I have heard that JLCpcb does not charge extra nonse cost for having multiple designs separated by a V-groove. Or do they? Do you have any recommendations?I would like to have a bunch of very small (say 40x20mm down to 10x20mm) pcbs manufactured. These are a simple test jigs for various components. I think using for example a larger (say 100 by 100mm) pcb V-grooved into smaller ones makes sense here. It should not add any more cost to manufacturing, other than the V-groove. Am I correct? Or are those Chinese guys going to charge me nonsense for this anyway and should I indeed leave them fully mill out the outline of 100(s) of small pcbs (which on my side I consider a nonsense from a manufacturing stand-point)?Thank you for suggestion and opinions.

author: wraper
author_rank: Unknown
timestamp: December 17, 2018, 09:14:30 pm
content: Just draw a line on mech layer and write V-cut.QuoteThey still charge some extra if designs are different. Ordering them separately would be cheaper.

author: Kean
author_rank: Unknown
timestamp: December 17, 2018, 10:28:27 pm
content: Some fabricators, including JLCPCB, have an option when ordering to request a panel. This is not ideal for production orders, but for prototypes it is fantastic - especially for small PCBs which can't be handled otherwise.You just select the option "Panel by JLCPCB" and enter the number of PCBs in the panel in X and Y direction. They will panelise your design, incuding tooling strips and V-grooves, and you can also get a matching stencil.I recently did this for some small PCBs (19x15mm and 18x12mm). The former was not quite a rectangle, and they routed out the corners. See pic attached of the delivered panel. I got 10 of these for $0.50 each, and the matching stencil (unframed) was $7. Of course shipping 30 panels (3 designs) plus 3 stencils was about $50 with an order value of just $33.If you want to panelise and document the V-grooves yourself, you just add the V-grooves to another mechanical layer, and include them in the dimension gerber, or a separate gerber with instructions (I just put V-cut as text next to them).

author: Yansi
author_rank: Super Contributor
timestamp: December 17, 2018, 10:51:56 pm
content: No, you did not get it. I have probably forgot to emphasize that the individual pcb segments are different from each other and I do not need a panel of 100 identical ones.Currently the design looks like 6 different patterns each two times repeated. (which at the end, ordering a 10pcb job would leave me with 6 designs by 20 pcbs each).Ok, I will try contacting them, but do not expect any positive outcome.

author: Kean
author_rank: Unknown
timestamp: December 17, 2018, 11:03:09 pm
content: OK, with different designs I think they can panelse for you as well - and I think the website even allows choosing multiple designs in a panel, though I have not used that. I am pretty sure that they will charge extra with multiple designs.They do like to charge extra for multiple designs as it has an effect (small as it may be) on their costs for PCB testing, and other handling. If you panelise youself, with V-cut markings in a gerber (as wraper showed), and keep it below the 100x100mm then you may be OK with few extra charges. Especially if the PCBs in the panel are all similar size, they may not take much notice of the different designs.

author: Yansi
author_rank: Super Contributor
timestamp: December 17, 2018, 11:17:54 pm
content: That is exactly what I am going after. Because of this "different design extra charge" bullshit. It is just bullshit, don't tell me it is not.I can understand, that having separate milled outlines within one design is a problem. (More boards to track, handle, pack, ...)But there is absolutely NONE difference in manufacturing and testing a design with, or without being separated by V-cuts.If I have say 10 different designs on a single PCB sheet (separated by just silkscreen or such), I get no extra charge.If I separate those 10 designs by V-cut, I should be only charged extra for the V-cut, as that is the ONLY manufacturing step added after testing. And I think that V-cut is way faster and cheaper, than having those 10 designed each outline fully milled apart.Or have I missed something?//I've sent inquiry to Allpcb and Jlcpcb about this.

author: Kean
author_rank: Unknown
timestamp: December 17, 2018, 11:26:23 pm
content: Quote from: Yansi on December 17, 2018, 11:17:54 pmNope, you're right. Most of their processes must be pretty well automated/streamlined by now so that any extra cost should be negligible.But you may still find it is cheaper to do separate panels and get more of each PCB that you actually need. It will likely increase shipping cost, so you just need to compare one option against the other. You can always keep the extra PCBs for a rainy day, or give them away, or sell them on ebay/Tindie. Small bare PCBs are usually easy & cheap to post worldwide as a letter.