OSHPark PCB Rules

I’ve had a couple boards made with OSHPark. But up until now I’ve used very conservative rules to make sure they work. I’m starting to work with increasingly smaller parts and starting to bump up against my rather conservative rules. I found the OSHPark design rules but I’m not 100% sure how they map to some of the KiCad setting. Does anyone have KiCad screenshots of the setting you would use for OSHPark?

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Yes, but I can’t upload images yet.

The most aggressive set of rules I’ve used with them so far was:

  • 6 / 6 for tracks and 25 / 13 for vias
  • mask clearance is always set to 0
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>>>Yes, but I can’t upload images yet.

Well, you can upload your image(s) to another site (ImageShack, to name one) and then put a link in your document here.
This, until it’s possible to upload images here too…

–Geert

So in KiCad terms is that (in the design rules editor with inches selected)…

Clearance - 0.006
Track Width - 0.006
Via Dia - 0.025
Via Drill - 0.013

What I really wasn’t sure about was the Via Diameter and whether minimum annular ring was added once or twice. So should the Via Diameter be 0.027 or 0.020?

I don’t speak for OSHPark, but it would seem the minimum annular ring would be about the same as the minimum track width. Based on that, the minimum via pad diameter would be the minimum drill diameter + 2track_width = 0.013 + 20.006 = 0.025.

I agree with Dave’s math, but I always use 0.027 for the via diameter because I don’t do super tight designs myself. On PCBnew, this shows up as:

And I set it up like this in the Design Rules dialog:

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I’ve done a bit of searching, and it seems that you can’t import a “.DRU” design rules file into KiCad. I’m guessing that’s the case, although would be useful for different board houses.

I agree it would be a nice feature if you could import design rules. Or at least make some design rules for differebt fabs and be able to select the one you need.

Right now I have to manually change/add design rules every time I start a new project.

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What about starting/saving various “starter projects” and then taking those and starting a new project (kind of like templates)? The risk is that you don’t save the project as a new one and you wipe out the template.

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Hmm, that is clever Chris. Did not think about that. Might try that out with a new project.

That solves the problem for an initial design, but what if you decide to change the fabricator later? Like when you move a design from a prototype fabricator to a more high-volume fabricator? This is a case where I like Eagles .DRU files.

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Yes, you’re right. However, once used one set of settings, and having layout the whole board, even when changing the settings, you might have to do all over again… Or change all via’s or something like that.

Right, at a certain point it’s going to become a manual process. The “beginner” files would just be about making it a little easier.

But you’ve already mitigated that risk by putting it in version control, right @ChrisGammell? :slight_smile:

On the subject of OSHPark PCB Rules… I had an odd thing happen yesterday. I had uploaded my gerbers and was getting ready to check out, when I was prompted with an “upgrade” option… swift service and higher tolerances. For swift service, I could have the boards delivered in one week (I think) for an extra $30… for the higher tolerances, I would have been able to submit a 2 layer board with 5mm traces and some smaller version of their via spec.

It seemed odd, because I’d never seen that as an option before that I can recall. Letting me know I could have used 5mm traces when I’m uploading gerbers seemed a little late in the process to tell me :slight_smile: I did pay for the swifter service though.

Nope, those are new offerings, that’s why you didn’t see them before.

I wonder if they are doing some A/B testing, because I only see “Super Swift Service” for $89 extra, which I personally think is too much. $30 sounds more reasonable.

Could be. My thought was that it was based on board space availability, selling open spots on boards about to be shipped off at a premium over putting you in the queue. And yes, $89 is too rich for my blood, particularly if I’ve already got the expectation that it’s going to be two weeks. If I wanted it faster, I probably wouldn’t have gone to OSHPark in the first place.

I made a pretty simple KiCad template for OSH Park a while back, it might be a good start. I was planning to attach it, but it seems that isn’t allowed… Let me know if there is interest for it and I’ll upload it some other way.

Edit: I uploaded it to my blog: prjct.net/download/osh-park_2_layer_standard_order.zip

The upload is possible, you need to have a slightly higher “trust” level though. That will happen after a short amount of time. See here for more info: https://meta.discourse.org/t/what-do-user-trust-levels-do/4924