[time-nuts] Re: in-ground clock room

[Gilles Clement]

With a slight cantilevered cavity at the base, 
instrumental as a *nut cracker… o:))
* = time?

> Le 9 sept. 2021 à 18:35, Dana Whitlow <k8yumdoober at gmail.com> a écrit :
> 
> One might also consider mounting smaller items inside the cylinders of the
> engine block,
> to get the most out of its thermal mass.
> 
> Dana
> 
> 
> On Thu, Sep 9, 2021 at 11:03 AM Joseph Gwinn <joegwinn at comcast.net> wrote:
> 
>> On Thu, 09 Sep 2021 03:30:35 -0400, time-nuts-request at lists.febo.com
>> wrote:
>> Re: time-nuts Digest, Vol 209, Issue 6
>> 
>> 
>>> ------------------------------
>>>> Date: Wed, 8 Sep 2021 18:54:03 -0700
>>> From: Tom Van Baak <tvb at LeapSecond.com>
>>> Subject: [time-nuts] in-ground clock room
>>> To: Discussion of precise time and frequency measurement
>>>      <time-nuts at lists.febo.com>
>>> Message-ID: <4037f6cb-ade3-8c01-8c36-7edf193274d6 at LeapSecond.com>
>>> Content-Type: text/plain; charset=utf-8; format=flowed
>>> 
>>> I am considering a below ground "clock room" away from the house. This
>>> will be for some low-drift quartz oscillators and also a couple of
>>> precision pendulum clocks. The goal is long-term, unattended, and very
>>> undisturbed operation.
>>> 
>>> For scale, assume the room is 1 meter × 1 meter × 2 meters deep. So
>>> that's vastly smaller than digging a basement, but much larger than
>>> drilling a 8 inch round pipe. Digging down gives some natural isolation
>>> and temperature regulation. A couple tons of concrete gives high
>>> stability vertical walls for the pendulum clocks.
>>> 
>>> If any of you have personal or professional experience with the design
>>> or construction of this sort of thing, especially experience with
>>> precast (utility) vaults or poured concrete, please let me know.
>>> 
>>> In case this gets too off-topic for time-nuts, off-list email to me is
>>> fine (tvb at leapsecond.com).
>> 
>> As others have said, it may not be economically practical to build an
>> underground clock room.
>> 
>> Assuming that you have a basement of other suitable room in your
>> house, I'd suggest an insulated box or room containing a big lump of
>> iron riding on an inner-tube suspension of some kind.   The big lump
>> of iron can be a 500-pound truck engine head or block from a
>> junkyard, steam cleaned (to remove oil) and painted (to keep the rust
>> under control).  Drill and tap holes as needed for mounting.
>> 
>> This box/room plus block can be set up as a temperature-controlled
>> oven with a few extra components, including a PID controller.
>> 
>> Bolt a thick plywood floor to the top of the iron hunk, and attach
>> the clocks to this floor.
>> 
>> Joe Gwinn
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