I need to have an electrical probe machined; but I am unsure how to specify my requirements. I am an electrical engineer with only moderate mechanical knowledge.
The probe will be machined from 0.125" diameter stainless steel round stock. The last 0.25 inch before the point necks down to a smaller diameter - maybe 0.031" - 0.062".
My question is in how to specify the pointed end of the probe. I want it to be sharp enough to dig in a little to the circuit under test but not so sharp that the point is fragile. Also, I don't want to specify overly-tight tolerances and push up the cost.
What is "sharpness"? Is it the angle leading to the point or is it the diameter at the very end?
My initial stab at it would be something like: "a cone with 60 degree angle sides". But this seems to imply an infinitely small point.
Should I specify a flat end of a certain diameter? (i.e. a conical frustum instead of a cone?)
And generally, "Is this design practical to produce at low cost?"