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Questions relating to designing PCBs
By celem
#181531
I don't know if this is possible but I would like to design a PCB with the edge in a saw-like edge. My goal is to be able to assemble two long thin PCB boards into a 7/8-inch diameter plus shape with the edges having the saw-like edge aligned such that I can then screw the assembled boards into a threaded cavity. While I have seen some hints concerning half-holes, I haven't seen anything for this design method.
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By leon_heller
#181533
I can do that with Pulsonix, by editing the board edge manually. It might be rather tedious, and you will find it difficult to find a company that will make them.

The enclosure is going to be very expensive.
By lyndon
#181542
You would be much, much better served by making/having made a threaded "nut" with threads on the outer edge and having a slot that the board can fit into than trying to thread the board itself.

I'm struggling to see what the benefit of your approach would be. Care to share?
By celem
#181548
The benefit was simply to reduce parts count and complexity. I originally considered using a section of hollow threaded shaft and attaching the PCB within, and that would still work, but I thought about having the board with threaded edges would be an elegantly simple solution, even though designing the PCB is complex.

The shaft that it must thread into is 7/8"x14 NF threads. I am making a depth sensor where a plunger is raised or lowered vertically through a square copper tube section that is soldered to the PCB. The PCB will contain a ATTiny85 ATmel microcontroller that will sense plunger depth using an optical sensor and provide visual and audio outputs when depth is determined to by outside parameters. The plunger offers no resistance so while stability is important, strength is not.
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By Ross Robotics
#181555
Find cross section of the right screw/bolt with detailed measurements, copy those measures into Eagle. Eagle has precision measurement tools..
By lyndon
#181612
I would prototype it first. Without tilting the routing head (which the PCB shop may not be able to do), the "threads" won't match the thread angle of what it's screwed into. The FR4 board substrate might deform enough to fit the threads properly though. Just don't screw it in too tight, or you may end up with stress points at some solder joints.

It occurs to me that if the thing you're screwing this into has "normal" V-threads, then an easy test might be to take a piece of PCB the rights size, chamfer one end to lead it into the home and then try screwing it in to see if the threads on the pipe cut a matching thread on the board.
By InactiveUser001
#181726
Expect a round radius on internal corners as they will use something like a 1mm routing bit minimum, the most common one is 2mm which allows a good stack of boards, the smaller the routing bit the less they can stack together and hence the more they may cost.