Posts: 378
Threads: 119
Joined: Dec 2009
Diameter would be .156 OD. .187 OD will work too, but gets very close to through hole plating and this is used on the upper posts. Now we just need a reliable way to repair the back case holes that hold the battery contact in. I've been toying with the idea of glueing the contact to the case and then using short (.25) screws to attach it to the post. Other suggestions?
Aluminum standoffs from Keystone Electronics Corp PN 1801B, Mouser PN 534-1801B
2-56 x .25 lg Pan Head screw, Mouser PN 534-9355
2-56 x .75 lg Pan Head screw, Mouser PN 534-9357
Edited: 11 July 2012, 8:06 p.m.
Posts: 80
Threads: 14
Joined: Sep 2010
Hello Everyone,
Well the Delrin posts seem to be working quite well so far.
Here are my final specs for this case, a HP41C tall key model with the tall cylindrical extrusions inside the case back lower section.
Delrin posts:
0.176" dia. 0.250" length, drilled and threaded all the way through for 4-40 NC screws
Post holes milled out to about 0.065" deep
4-40 NC Brass screws shortened to about 0.200" of thread. Heads turned
down to 0.160" dia.
Tried epoxy first but one failed. Tried super glue next to much better effect.
I trimmed about 0.010" off the top of the posts to achieve the final fit between case, motherboard, elastomeric connector and keypad board.