19 Jan
2011
19 Jan
'11
12:56 p.m.
On 01/19/2011 06:35 AM, gene heskett wrote:
nah It will pull itself into a black hole of course :)
Silver solder, or just silver bearing solder?
likely both. It is a very well equipped lab. There was a small
hand-torch in there as well. Though I think it was mostly used as a
spare lighter :)
On Wednesday, January 19, 2011 12:12:05 am Robin
Gareus did opine:
I guess Joern's Studio is only 3 or 4 rooms. It's mostly because he
mentioned wall sockets that I suggested this.
It can also be the wall (or ceiling-mounted) type. I think they're
called raceways or just cable-tray.
[..]
On 01/19/2011 03:39 AM, gene heskett wrote:
Ahh, so, here that is called "conduit" and can be metallic or more likely
in recent years, plastic, glued up just like water pipe and smoother to
pull wires through than the metallic stuff. Both need plenty of "snot" on
the wires for a temp lubricant if going very far, and about 3 bends is
still the limit for one pull run. On Tuesday, January 18, 2011 09:16:00 pm Robin
Gareus did opine:
nope. I mean tubes like pipes in the wall or floor that allow one to
easily replace cables that run inside those tubes. It'd still be a major
re-wiring task but at least one can change the wires easily compared to
in-wall mounted cables.
Hi Joern,
If it is an option: use Leerrohre (DE for "empty tubes" ?) to make it
future-proof, rather than to rely on cable-standards. In a few years
you may want to replace coax with optical or whatever.
I think that would translate to wave-guides in English It is
currently running inside the ALICE detector @LHC.
Yikes. If that ever collapses, it will emp into smoke, and and all
electrical stuff for many meters around it. That, it can be said is NOT a
friendly environment. Even your $15 Casio wrist watch is in danger if you
move too fast in that.
The magnetic field you mean? The tricky part is get close enough. You'll
need a few weeks to undo all the screws on the "enclosure" and not get
kicked out in the meantime. Once you get in there you don't need to
move, the electrons inside the watch are already moving fast enough. The
only workaround is to have only short interconnects and lots of bulk in
between them. Luckily this is an OT post:
http://blogs.discovermagazine.com/badastronomy/2010/09/21/dont-cross-the-lh…
I will allow the comment that when fabricating
wave-guide parts and
filters for 7Ghz work, which I have done a few of decades ago, those
were usually silver soldered because the regular tin/lead solders
surfaces oxidized with time much worse, screwing with the skin effect
losses. Silver oxide may look fugly, but is still a pretty fair
conductor when frequencies are in the realm where skin effect reigns
supreme. Just as true inside the wave- guide as it is on the skin of
a coax conductor.
interesting. I do remember a drawer with at least 15 different kind of
solder. Now I know what that silver stuff in there was in there for :) The latter seems to top out
at about 3% siver in an otherwise eutectic allow, but is a noticeably
stronger solder mechanically that doesn't oxidize near as fast. I don't
use anything else myself but it does raise the iron temps needed by
50-100F, which leads to needing to clean the tips more often.
Real silver solder needs a propane or better torch or a tig for heat and
you use a borax based flux that melts and forms an airtight puddle of
liquid glass over the joint so the oxygen is sealed away from the hot
metal, facilitating a nice clean joint when you feed the silver wire in to
make a 'sweat' joint, like the plumbers do for copper piping. But the
borax should be chipped away and removed once it has cooled as its a bit
lossy at those frequencies. Properly done, you get the 'sweat' started,
and pull it along by moving the heat (it crawls to the heat) until you have
the joint level full of silver but no extra beads sticking out. Don't
apply any more silver than what it takes to just seal the joint. Dry fit
accuracies of less than a 5 thou gap work very well, wider gaps are
correspondingly harder to control. You really need a milling machine to do
wave-guide parts correctly.
Thanks robin
Thank you for the lengthy explanation.
ciao,
robin