Is it OK to specify a blank hole for unused pins this way?

[Pjdd]

I've been designing and making PCBs for well over 50 years but have outsourced only a few for production. Those few were before it became standard practice to send designs as Gerber files. I have what may be a silly question:

When ordering a PCB, is it OK to specify the same size for aperture and pad for unused through-hole pins that don't need to be soldered? That is, there won't be any copper left around the hole after drilling. Any trace left won't be a problem. The object is to maximize clearance for tracks running between the unused pins.

The pads are there only as placeholders to provide coordinates for drilling. I just want to be sure that it won't confuse a human checking the design prior to processing it.

For example, I'm designing something that uses only half of the pins coming from an off-the-shelf module mounted on the main board. Here's an illustration:

 

[andre_luis]

I fear that drilling accuracy is worse than for routing; anyway, keep in mind that soldering unused pins somehow improve the mechanical robustness of the connector as a whole, leaving less stress on the remaining ones.

 

[barry]

Holes with no pads are done all the time. They're called "holes". But I suggest you make the pad smaller than the hole to account for misalignment.

 

[Pjdd]

Thanks for the replies. Yes, I'm aware that leaving some pins unsoldered will weaken support for the device. But only pins with tracks running between them will be left unsoldered and I'm confident that the rest will provide enough support.

I generally don't use tracks and spacings less than 10 mils, so I feel that slight inaccuracies in drilling shouldn't pose a problem. That's why I said "Any trace left won't be a problem". I was visualising some tiny arcs of copper left on one side of a blank hole due to minor inaccuracies in drilling.

Anyway, my question is about the way blank unused holes are marked in the design. My old CircuitMaker 2000 doesn't seem to have any other way to represent such a hole.

 

[D.A.(Tony)Stewart]

It may be OK but it is more often to use a standard pad and plated thru hole for all pins. Teardrop pads promote better mechanical strength to prevent shear fracture failures from external forces.

Other details https://www.protoexpress.com/blog/what-is-pad-pcb-design-development/

I too remember laying out boards with tape and colored pencils on Mylar grid paper for digitization.

 

[barry]

It may be OK but it is more often to use a standard pad and plated thru hole for all pins. Teardrop pads promote better mechanical strength to prevent shear fracture failures from external forces.

Other details https://www.protoexpress.com/blog/what-is-pad-pcb-design-development/

I too remember laying out boards with tape and colored pencils on Mylar grid paper for digitization.

Not true.

Holes with no pads are used all the time.

And teardrops have zero functionality on a pad that's not connected to a trace.

 

[marce]

In the past, on simple single and double sided boards, this was often done, for in house production... I can remember had drilling PCB's, that we made in house... That was many years ago, and often with tap up designs... Always marked the holes with a doughnut pad.

 

[D.A.(Tony)Stewart]

It depends greatly on the mechanical vibration stress-strain relief of pins vs header screws.

Can anyone generalize without knowing how the external forces affect the results?