'Gluing' a broken glass antenna insulator.
 

May I insert a practical subject into this news group which
frequently discusses SWRs, the speed of electromagnetic
propagation and other exotica?
Ever see those adverts where a hefty guy wearing construction
Safety Helmet is hanging from one little spot of 'Krazy Glue'
from a steel beam?
Last winter I broke a very nice 8 inch (straight glass not an egg
shell) insulator into two almost equal pieces. :-(
A 'clean' break in the ribbed section, no lost pieces or chips of
glass, the broken two pieces mated perfectly.
So a couple of days ago I 'glued' it with Crazy Glue; one of
those cyano-cryolate (sp?); or whatever the proper name is!. Used
a generous but not too overflowing amount.
At house temp. it 'seems' to have made a very strong join. And,
holding it, so almost, did my fingers when the vapour from the
glue seemed to flow away from the join and collect on them!
However I've escaped.
Whether I will use it again I'm not sure; probably can't depend
on it.
But I thought I might set up a test jig; by hanging from it a
plywood platform a few inches above the ground and loading that
with concrete blocks/bricks etc.
Any ideas comments what the 'strength' of an unbroken one would
be. That is to say what would be a 'normal loading for an
insulator of this type. I've seen pictures of wire antennas with
incredible loads of, say, ice, on them. And often something will
break; but those glass insulators look incredibly strong, unless
you drop one as I did.
Regards. Terry.
A few miles from where, in 1901, Marconi received the first
Transatlantic wireless telegraph signal.

Terry wrote:

May I insert a practical subject into this news group which
frequently discusses SWRs, the speed of electromagnetic
propagation and other exotica?
Ever see those adverts where a hefty guy wearing construction
Safety Helmet is hanging from one little spot of 'Krazy Glue'
from a steel beam?
Last winter I broke a very nice 8 inch (straight glass not an egg
shell) insulator into two almost equal pieces. :-(
A 'clean' break in the ribbed section, no lost pieces or chips of
glass, the broken two pieces mated perfectly.
So a couple of days ago I 'glued' it with Crazy Glue; one of
those cyano-cryolate (sp?); or whatever the proper name is!. Used
a generous but not too overflowing amount.
At house temp. it 'seems' to have made a very strong join. And,
holding it, so almost, did my fingers when the vapour from the
glue seemed to flow away from the join and collect on them!
However I've escaped.
Whether I will use it again I'm not sure; probably can't depend
on it.
But I thought I might set up a test jig; by hanging from it a
plywood platform a few inches above the ground and loading that
with concrete blocks/bricks etc.
Any ideas comments what the 'strength' of an unbroken one would
be. That is to say what would be a 'normal loading for an
insulator of this type. I've seen pictures of wire antennas with
incredible loads of, say, ice, on them. And often something will
break; but those glass insulators look incredibly strong, unless
you drop one as I did.
Regards. Terry.
A few miles from where, in 1901, Marconi received the first
Transatlantic wireless telegraph signal.

Cyanoacrylates (crazy glue) are near worthless in a humid and/or UV
environment- guaranteed to fail.

The anaerobic cements by Loctite create a bond stronger than the glass.
Pick up some rear view mirror cement with its primer.

Dale W4OP

"Terry" wrote in message
...

Last winter I broke a very nice 8 inch (straight glass not an egg
shell) insulator into two almost equal pieces. :-(
A 'clean' break in the ribbed section, no lost pieces or chips of
glass, the broken two pieces mated perfectly.
[snip]
Regards. Terry.

Terry -

I would recommend finding a glass blower (either artistic or commercial)
I may be possible to "reheat" both sections - while still retaining their
shape -
and splice the pieces together in a "plastic state"

w9gb


Do not use Reply
Only reply through ARRL forwarding service to W9GB

On Fri, 11 Jul 2003 09:48:41 -0230, Terry
wrote:
Last winter I broke a very nice 8 inch (straight glass not an egg
shell) insulator into two almost equal pieces. :-(
A 'clean' break in the ribbed section, no lost pieces or chips of
glass, the broken two pieces mated perfectly.
So a couple of days ago I 'glued' it with Crazy Glue; one of
those cyano-cryolate (sp?); or whatever the proper name is!. Used
a generous but not too overflowing amount.

Two problems arise. One is in the amount of handling these pieces met
with your examination. Handling being literal to fingers touching
what they should not. The oils in skin could easily create a poor
bond (regardless of cement chosen). Two is the amount of cement used.
You clearly used TOO MUCH.

At house temp. it 'seems' to have made a very strong join. And,
holding it, so almost, did my fingers when the vapour from the
glue seemed to flow away from the join and collect on them!

This "house temp" description reveals the third point of failure.
Cement joins invariably fail due to differences in the coefficient of
thermal expansion between the cement and the material(s) being
cemented. For glass, the variation of outdoor temperature could
easily see the materials pop apart sitting on a picnic table, much
less in service.

Regards. Terry.
A few miles from where, in 1901, Marconi received the first
Transatlantic wireless telegraph signal.

Hi Terry,

Did Marconi use these 8" monsters? Take this as an opportunity to
enjoy a capricious doubling of your insulator stock.

73's
Richard Clark, KB7QHC

Terry wrote:

Thanks to all who replied and gave advice. Terry.

Richard Clark wrote:

On Fri, 11 Jul 2003 15:06:48 -0230, Terry
wrote:

My next post may be "How to remove Krazy Glue ......?

Hi Terry,

Try acetone.

73's
Richard Clark, KB7QHC

Well me son!
What a nice (and knowledgeable) bunch here?
First I drops it and it breaks!
Then I uses the wrong glue!
And they still gives me good advice.
T'anks. Terry.

Dale Parfitt wrote:


Terry wrote:
Last winter I broke a very nice 8 inch (straight glass not an egg
shell) insulator into two almost equal pieces. :-(
A 'clean' break in the ribbed section, no lost pieces or chips of
glass, the broken two pieces mated perfectly.
So a couple of days ago I 'glued' it with Crazy Glue

Cyanoacrylates (crazy glue) are near worthless in a humid and/or UV
environment- guaranteed to fail.

The anaerobic cements by Loctite create a bond stronger than the glass.
Pick up some rear view mirror cement with its primer.

That looks like a better idea, but be careful - there's more than one
kind of rear view mirror cement. A friend in Sweden was sold a pack of
cement that only cures in the UV from sunlight... up near the Arctic
circle... in winter.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek

On Fri, 11 Jul 2003 09:48:41 -0230, Terry
wrote:

May I insert a practical subject into this news group which
frequently discusses SWRs, the speed of electromagnetic
propagation and other exotica?
Ever see those adverts where a hefty guy wearing construction
Safety Helmet is hanging from one little spot of 'Krazy Glue'
from a steel beam?

I used to work in advertising. Don't believe everything you see :-)

Otherwise, try the web sites for the Wireman, Surplus Sales of
Nebraska or whatever -- they got lots of insulators; the Surplus
folks, in particular, have lots of pretty glass jobs.

Bob
k5qwg