Re: Terry Gap vs. TCBOR...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Brett Miller <brmtesla2-at-yahoo-dot-com> 

Ed,

 > My real interest was whether epoxy cement could
 > stand the temperature.

That's a very good point and I may have some insight
for you on that.  My TCBOR uses PC-11 two part epoxy
(in addition to two brass bolts) to fix the pipes at
their proper distances.  It is an amazing glue, which
can be used to fix a hole in the hull of a boat and
will even cure underwater.  The can says "Marine
Power" on it.  However, it is not designed to
withstand high temperatures..(probably wouldn't fair
too well immersed in Liquid Nitrogen either I'd say)
During runs approaching 3 minutes I have noticed some
softening of the epoxy.  Luckily, both the bolts on
each pipe have ensured that spacing doesn't change.
Nevertheless, I could smell the epoxy in the air.
Just another reason I keep my runs short with that
particular static gap.

In the static gap comparison experiment I am preparing
to perform, I will keep the runs extremely short so as
to prevent this and powerarcing from becoming an issue
and skewing the results of any possible learning
opportunities.

 > In the gaps I've made I mounted the pipes on either
 > ceramic insulators
 > or transite sheet, which could stand pretty high
 > temperatures but the
 > idea of gluing them in place (or using PVC pipe as
 > in some of the blown
 > types) is quite appealing.  Others have reported
 > good success but I've
 > always been too chicken to waste the time.

You probably did the right thing.  I will not be
gluing future gaps, certainly not for any permament
installations.  The TCBOR was something I made as a
starter gap, but ended up using more and more many
more years than I ever thought I would.

-Brett

 > Ed