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Opening Cs Tube

SW
Skip Withrow
Fri, Sep 1, 2023 6:06 PM

Hello time-nuts,
TVB asked how I opened the CS tubes, so here it is.  It's is fairly easy
really.
First, find your safety glasses.  There will be bits of metal and cutoff
blade going everywhere.
I use a right angle grinder with a cheap metal cutting blade.
I cut around the tube just to the outside of the end cap weld seam on each
end.  Try not to cut too deep, just enough to get through the case.  You
now have the end caps removed.
Then, make two cuts lengthwise along the central cylinder lined up with the
frame of the internals of the tube.

On the old tubes (non high performance) cutting the window in the microwave
mu metal shield exposes the waveguide nicely.  On the new tubes there are
the two shields and a lot less working room, I have deemed it not worth it.
Regards,
Skip Withrow

Hello time-nuts, TVB asked how I opened the CS tubes, so here it is. It's is fairly easy really. First, find your safety glasses. There will be bits of metal and cutoff blade going everywhere. I use a right angle grinder with a cheap metal cutting blade. I cut around the tube just to the outside of the end cap weld seam on each end. Try not to cut too deep, just enough to get through the case. You now have the end caps removed. Then, make two cuts lengthwise along the central cylinder lined up with the frame of the internals of the tube. On the old tubes (non high performance) cutting the window in the microwave mu metal shield exposes the waveguide nicely. On the new tubes there are the two shields and a lot less working room, I have deemed it not worth it. Regards, Skip Withrow
R(
Richard (Rick) Karlquist
Sat, Sep 2, 2023 7:16 PM

Perhaps some trivia about the CBT may be of interest:

HP had some sort of manufacturing process for the CBT that involved
building tubes and sealing them up and maybe pumping them down,
but without breaking open the Cs ampoule.  Some sort of testing was
done on them.  Then the ones that failed the test had to be
cut open and rebuilt.

Anyway, the model maker (machinist) who managed the engineer's
machine shop handled the cutting open process in the shop he
managed.  It was done using a fairly large lathe.  He was able
to cut open the envelope without any damage to the innards.
IIRC, the machinist was named Norm.  The lathe was probably
bigger than any lathe a time-nut could hope to own.

I tried to get Norm to explain why all this was done, but I
never understood what he was talking about.  He was constantly
cutting open CBT's, it seemed.

Rick N6RK

On 9/1/2023 11:06 AM, Skip Withrow via time-nuts wrote:

Hello time-nuts,
TVB asked how I opened the CS tubes, so here it is.  It's is fairly easy
really.
First, find your safety glasses.  There will be bits of metal and cutoff
blade going everywhere.
I use a right angle grinder with a cheap metal cutting blade.
I cut around the tube just to the outside of the end cap weld seam on each
end.  Try not to cut too deep, just enough to get through the case.  You
now have the end caps removed.
Then, make two cuts lengthwise along the central cylinder lined up with the
frame of the internals of the tube.

On the old tubes (non high performance) cutting the window in the microwave
mu metal shield exposes the waveguide nicely.  On the new tubes there are
the two shields and a lot less working room, I have deemed it not worth it.
Regards,
Skip Withrow


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Perhaps some trivia about the CBT may be of interest: HP had some sort of manufacturing process for the CBT that involved building tubes and sealing them up and maybe pumping them down, but without breaking open the Cs ampoule. Some sort of testing was done on them. Then the ones that failed the test had to be cut open and rebuilt. Anyway, the model maker (machinist) who managed the engineer's machine shop handled the cutting open process in the shop he managed. It was done using a fairly large lathe. He was able to cut open the envelope without any damage to the innards. IIRC, the machinist was named Norm. The lathe was probably bigger than any lathe a time-nut could hope to own. I tried to get Norm to explain why all this was done, but I never understood what he was talking about. He was constantly cutting open CBT's, it seemed. Rick N6RK On 9/1/2023 11:06 AM, Skip Withrow via time-nuts wrote: > Hello time-nuts, > TVB asked how I opened the CS tubes, so here it is. It's is fairly easy > really. > First, find your safety glasses. There will be bits of metal and cutoff > blade going everywhere. > I use a right angle grinder with a cheap metal cutting blade. > I cut around the tube just to the outside of the end cap weld seam on each > end. Try not to cut too deep, just enough to get through the case. You > now have the end caps removed. > Then, make two cuts lengthwise along the central cylinder lined up with the > frame of the internals of the tube. > > On the old tubes (non high performance) cutting the window in the microwave > mu metal shield exposes the waveguide nicely. On the new tubes there are > the two shields and a lot less working room, I have deemed it not worth it. > Regards, > Skip Withrow > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com >