A replacement for the HP-41 zebra connector

[mfleming]

(03-31-2017 02:44 AM)Nate Martin Wrote:  using an older motherboard that had the nuts to keep it in place on the posts, the backside of the motherboard was too rough with the solder connections and two penetrated one of the line traces. I will try to post a pic soon. The trace still has continuity but it looks like it hit the trace dead on which could cause a short with those solder connections if not a broken trace. I could probably resolve this issue with a little klapton tape on the motherboard before installation.

I would definitely like to see a picture! I've had the flex material distort and dimple from solder bumps that lay along a line drawn between the two support posts, but I've not seen a CPU board with protrusions outside of the contact footprint. A final design of the flex connector replacement should not extend past the left/right boundaries of that footprint. Was the flex material actually punctured, or just severely distorted?

Based on the thickness of the zebra connector spacer frame, I think a support material diameter of 3/32" (2.5mm metric, or about one seven-hundredth of a fathom ) would be about the right size. Both splines I supplied were 25% - 50% larger, which would account for the poor fit.

Thanks for testing this on a calculator I don't have!
~Mark