PDP-8 screws

[Jon Elson]

On 10/26/2018 09:19 PM, Steve Malikoff via cctalk wrote:
> William said
>> One the original PDP-8 ("Straight 8"), the front panel has two aluminum
>> strips on the sides, one on the left and one on the right. Each should have
>> a pair of flathead countersunk screws, likwly Phillips head.
>>
>> Can someone tell me the exact specs, basically thread, length, head, and
>> material of the screws?
>
> I have no idea what the straight eight screws are, but for comparison the sort of screws in
>
The screws in 19" relay racks are almost all 10-32.  
Flat-heads come in 60, 82, 90 and 110 degree angles.  I'm 
guessing these might be 82 degree, that is quite standard.  
To avoid marring the panels, there were things that had a 
nylon "washer" or ring that was capped by a metal "washer".  
These both had an internal angle that matched the screw 
angle.  The metal washer was shorter than the nylon one, so 
ONLY the nylon washer touched the panel.  The metal washer 
was to prevent the nylon one from being squashed by the 
screw.  I have NO IDEA where you would find these things 
today, maybe they still make them.  But, they used to be 
quite common where equipment racks were used.

Jon