[Milsurplus] Re-attaching vacuum tube envelops to their bases

[Larry Christopher]

Hi everyone,

I am new to your group,.  although I don't know much about military 
surplus.
I collect Tektronix tube oscilloscopes from the 50's and 60's, so I am sure
many of the issues and problems will be the same.

In regard to reattaching tube bases, I have just finished a project 
which required that
I remove about 40 crt's from 40 scopes and reattach the base to the 
glass of the tube.

In order to do this, I used:

Elmer's  PROBOND Polyurethane glue.

 I stand the tube on its base and run a bead of the glue around the 
joint. Sometimes, if the old
glue is reallly flaky, I use a sharp instrument like a dentist's pick to 
clean out some of the old
glue. But it doesn't seem to be a requirement for a good bond.

Once the bead is all around the tube, the tube needs to be kept upright 
on its base overnight. The
glue foams up and fills the joint nicely. After all has hardened, I use 
and Exacto knife and sometimes
a razor blade to trim the bead flush with the base of the tube. If there 
are gaps that would permit
moisture to get into the tube base, I redo the glue operation to seal them.

These tubes have quite a bit of voltage on some of the base leads, and 
so far I have had no problems.

Any questions, please email me.

Larry Christopher
Surrey BC Canada