Glue advice

Hello all,

I’m looking for a solution to a set of mourning pendants that I’m
building. Each contains a 6mm diameter pyrex glass tube, w/ about a
2mm wall. This leaves a 2mm cavity which is filled w/ ash. The cages
have been fabricated and the caps will be riveted in place.

What I am looking for is a durable, flexible sealant for the 2mm
opening in the tubes. A small metal plug will fill the opening and be
glued in place. A cap will cover the opening, so it won’t be visible.
It needs to be water tight and somewhat pressure resistant-- he dives
occasionally. My first thought, of course, was silicone. It is
flexible and adheres well to glass. I’ve had fish tanks for years,
some over 90 gallons that were siliconed and never failed.

Pasco Industries glue has been reccomended, but I am unfamiliar with
it. I don’t think a cyanoacrylate glue will give me the flexibility,
nor a resin type such as epoxy.

Any ideas?
Thanks, in advance,
Andy Cooperman

E6000 perhaps? UV6800 is recommended for UV protection.

I recently made some goblets from sterling silver, 18K/sterling
bi-metal and kilnformed glass. The glue I used to attach the metal
and glass came from Dymax and is intended for gluing glass and metal.
It’s an ultraviolet glue that can be used with an accelerator instead
of ultraviolet light. The accelerator has a slightly yellow tinge and
so I wouldn’t recommend it with clear glass because the yellow tinge
does show. It didn’t show where I glued the glass to a piece of 18K
bi-metal or to dark glass. This glue isn’t flexible, however.

Their website is

Another glue that glass artists use is called Hxtal, a 2 part epoxy.
I’m not sure how well it works when gluing metal to glass. Here’s a
link to a place where you can buy it

I have no personal experience with Hxtal. Someone on the warmglass
board may be able to provide you with more about it.

A flexible glue that some glass artists use to attach metal to glass
is called E6000. My experience with it is that it doesn’t hold up well
when it gets wet repeatedly.

I hope this helps -

Geri Comstock
Glass Artist/Jeweler

Hi Andy,

Spend some time heRe:
I’m afraid I don’t know enough about these products to advise you on
specifics, but a friend of mine who worked on airplanes recommends
Loctite adhesives for just about everything.


Hi Andy,

I work with lots of different adhesives (lapidary) and maybe I can
help. Here’s some things to remember:

The cyanoacrylates actually need moisture to set and cure. Cleaning
the pieces to be joined with 91% isopropyl alcohol (never acetone)
then breathing on one piece just before applying pressure assures a
solid join, but is usually not necessary. However, the
cyanoacrylates are somewhat sensitive to shock, so a sudden rap can
break the bond on the older formulations. Loctite’s new
"Professional Grade" seems to create a very, very strong bond which
is NOT shock sensitive, and easily withstands heat to 350 F plus.
But the glue is not flexible at all, so shouldn’t be a first choice
for your application. While you can use a thicker cyanoacrylate with
an accelerant, it weakens the join 30-50%, according to Loctite and

The 2 part epoxies are not very flexible, if at all, when cured, and
WILL break down in the presence of high humidity or water. Takes
some time, but they are not reliable if water is involved, including
the shower, trust me, been there and done that!

There is an adhesive from Norland Adhesives, that is clear and cures
with either UV (sunlight works fine) or heat. And as the cure
continues (it joins very quickly but continues to increase in
strength for many days), if glass is involved, the adhesive actually
penetrates the glass surfaces and becomes one with them. This bond
cannot be broken, but is not flexible.

The silicones mentioned, especially the 3M product, will create a
clear (available in clear, white and black) and flexible bond which
is quite waterproof. It would be my adhesive of choice for the job
you describe.

If you Google Loctite and Norland Adhesives you will find vast
on all kinds of adhesives. Considering that many can
withstand heat in excess of 400* F and have a tensile strength
exceeding aluminum, I’m surprised we don’t see wider use of them in
the jewelry world. Old prejudices, I guess.

Hope that’s of some help…I am a long time admirer of your
excellent work!

Wayne Emery
The Gemcutter

Hello Andy,

Sounds like this is an ideal job for caulking. Many companies are now
making clear, water-based caulking (no solvent stink). I’ve used it
similarly for a number of years, thanks to a heads-up from Keith

Hope all is well with you,
Linda Kaye-Moses

Use the silicone. Simple, easy, waterproof, flexible, and it takes
"an act of congress" to get the stuff off once it cures.


The best place that I know for glue advice is,
this gives lots of insight to different glues and what might be best
to use for a particular application. There are plenty of ideas and
backgrounds on certain compounds. The site may be able to give you

Beth Katz
Unique Solutions, Inc.
Paste and Powder Solder for Jewelers and Metalsmiths