Hi,
Well, still not strictly, strictly true !
In Ku & K band earth stations I've worked in, I've never seen shoulder screws
used, although the equipment used was mainnly from the USA.
Next to you precision adaptors, SMA torque wrenches etc in your personal goodie
box are sets of tapered pins, about 35-40mm long - that fit various diameter WG
mounting holes (the old metric vvs Imperial issue again).
You insert a pair of pins on diagonal corners then add bog-standard SS hardware
to the opposite diagonals & tighten. The tapered pins are then removed and
replaced with another pair of screws/nuts. This ensures absolute (?) internal
WG slot alignment. There are a few variations on this theme if you must have
absolutely minimum RL within that section of guide or if one guide face is
threaded. Hex-headed bolts are usually used.
That may explain why shouldered bolts are seldom seen.
Tapered WG pins fall into the 99.9999% unobtainium class of materials.
Kit
VK2LL
------------------------------
Message: 6
Date: Sun, 19 Sep 2010 10:15:17 +0000 (GMT)
From: Robert Atkinson <robert8...@yahoo.co.uk>
Subject: Re: [time-nuts] Semi-OT: Hardware for WR-90 waveguide
sections?
To: Discussion of precise time and frequency measurement
<time-nuts@febo.com>
Message-ID: <414785.76181...@web27102.mail.ukl.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Hi,
Not strictly true. Material is not important apart from environmental
(corrosion) issues, but that is not the only concern. WG-16 (British) / WR 90
flanges are not dowelled. They rely on the fastners for alignment. The correct
fastners are 5/32" shoulder screws (0.1557" dia 6-32 thread).
>>snip
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
