We recommend a small but nonzero line width; the fab will route so the edge of your board is at the center of your line, no matter how wide it is.
What is interesting is that I uploaded to OSHPark a Gerber with a 2"x2" board with 0.5" Edge Cuts line width. The automagic calculator on their web page calculated the board to be 2.5"x2.5" in size. This could be an anomaly caused by the Gerber that I uploaded; but I won’t know exactly what is going on until a board comes back from them in the upcoming few days.
2:
Filled zone clearance influenced by Edge.Cuts line width.
In a design, it was desired that one edge of a copper pour would not have any pull-back from one edge of the board. Is there some hack that will allow a design to accomplish this?
Or it could be a bug in their own board quote software (going to the bounding box of the drawn outline instead of the bounding box of the centerline of the outline.) Have you contacted them about this?
The only thing I can think of that might work (I haven’t personally tested this) is to set the zone copper clearance to zero (or the smallest number possible (1nm?)) and the edge outline to as thin as possible on the side in question (at minimum). Enforce the pullback on the 3 sides where desired by where you draw the zone edges. But this means that you can’t have a copper to zone clearance slightly larger than the netclass copper to copper clearances. This last point may or may not be an issue for your design.
No. There is already a board being fabbed by them with the Edge.Cuts exactly centered on the 2"x2" grid. I’ll know in a couple of days exactly what ends up getting made.
I’m not sure that’s even a bug, as it likely does a simply entity-bounding-box, and the design information provided is actually inside a 2.5" x 2.5" bounding box.
What may or may not happen to some parts of the design into later, is outside the realm of a bounding box calculator, and this is an artificial test case anyway.
But the pricing is based on the results of the board quote software (I’ve used OSHPark, and this is how they work), and this is the price that shows up in the shopping cart when the order is placed. The actually manufactured boards are based on the center-line of the edge cuts lines, and this example it should be 2x2. But because he used half-inch edge cuts lines the quote became based on 2.5x2.5 boards, ~1.5 times what it should be.
It will be interesting to see if @Sprig is actually charged only for 2x2 or if the original quote price for 2.5x2.5 is what he is charged.
I did not actually order the board as it was a design from a college group effort. However, the question came up because I have the board files and in discussion with the individual that did the upload to OSHPark a query was made about the Edge.Cuts layer and if that had anything to do with why the order was $0.20 more than expected.
It appears that the graphic lines were about 6mill thickness; and apparently the math works out for the extra cost.
I only uploaded the 500mil edge.cut graphic lines as an exercise to help determine what is actually going on.
As, this may have bitten me if one of the next boards will not fit into the enclosures I’m about to order.
ON EDIT: As of tonight, I have had additional conversation with the individual that ordered the board, and they went to examine their order and OSHPark sized the board order as 5.01"x5.01" (rounded up) and did bill them for the extra 0.01" squared. The boards are in the mail, and as soon as they arrive I should be told what the actual finished board dimensions ended up being.
This has been a LONG night, and I am still not certain exactly what the issue is; there appears to be more than one issue at work at any given point in time.
