240 peices total in the box, but only 80 of them are standoffs, the rest of them are screws and nuts.jbeale wrote: ↑Thu Aug 08, 2019 9:23 pmFWIW: 2.5 mm standoffs in black nylon https://www.amazon.com/Female-Standoff- ... 07D5T1TXV/
And I can't buy 2.5mm screws, they're next to impossible to find except internationally. Buying a screw with a larger head is easier than making a 3mm screw shrink to 2.5mm
For sufficiently loose values of "based on". It seems that the ISO 261 "first choice" values are based on a R10 series but rounded inconsistently. The "second choice" values seem to be based on R20 but with some values missing.
Also, changing the hole size would need to go back to the PCB designer. PCB software automatically sets/checks clearances between holes and traces. A small increase in hole size *may* cause a lot of grief for the PCB designer. Bigger holes = less PCB space for traces.
Good point, thank you!Greg Erskine wrote: ↑Fri Aug 09, 2019 6:39 amAlso, changing the hole size would need to go back to the PCB designer. PCB software automatically sets/checks clearances between holes and traces. A small increase in hole size *may* cause a lot of grief for the PCB designer. Bigger holes = less PCB space for traces.
Don't diss Torq, it's a spectacularly effective system, able to apply large amounts of torque, unlike hex.davidcoton wrote: ↑Thu Aug 08, 2019 8:58 pmThat's nothing. We get Torx, Hex, even crosshead clones that are neither Philips nor Pozidrive. And that's before anyone starts on the special security versions.
I have nothing against Torx. I hate the number of different standards (and non-standards) that result in a health-endangering weight in my toolbox, because I need to carry a variety of sizes for each of five different systems. Especially for those that are insulated to VDE standard, which makes for chunkier tools even before the insulation is added.
Maybe I hung out too long with old and reprobate machinists, but 2.5 mm → 3 mm is one of the other uses for rolling papers. Tear off a thin strip, lick it, roll it round the too-small screw and jam it in place.
At that point, who cares?
The xray pictures show no copper near the mounting holes, so 0.5mm is nothing.If you're worried people might accidentally drill through a trace, don't be there's several mm gap surrounding the holes, 0.5mm is well away from any trace.