Drilled to insert lights.
Drilled to insert lights.
a clay dam
drill glass block.
Purple LED lights with
wire in block
with bubbles and swirls.
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& Bottle Drilling
Drilling in glass block or bottles
is basically no different than drilling in normal glass.
If you use the appropriate speed, use low drill pressure and
plenty of water for lubrication, you won't have any problems.
Glass breakage with carbide bits is fairly common, but with a
good diamond bit, it is extremely rare. There are a few
very important facts and tips that will helpful when drilling
glass block or bottles.
There are numerous different
types and styles of glass block made by many different manufacturers.
Most have some type of design or pattern, however, for drilling
purposes, there are two important characteristics to be aware
of. Glass block can vary significantly as to the thickness
of the glass wall and some glass block is tempered. This
information is rarely disclosed on the block itself, but should
be considered when buying glass block for crafting purposes.
If you are drilling glass block
that has been installed in a wall, you don't have much choice
but to drill whatever is there. However, for craft projects,
it is good to be selective. If the glass block is 3/8"
thick, it will take three times as long to drill compared to
block with a 1/8" thick wall. Additionally, it will
triple the drill bit wear per hole, causing the bit life to be
only one-third as long. Some glass block and bottles are
tempered to increase the strength of the glass. Tempered
glass should be avoided if reasonably possible.
Experienced crafters who work
with glass block and bottles learn to search for different types
and styles to test. After drilling a sample of each, it
is obvious which has a thin wall and if any are tempered.
Also, crafters who are drilling lots of glass blocks or bottles,
normally develop some type of "clay dam" or pan drilling
method, so that it can be drilled under water to improve lubrication
and extend drill bit life. The "clay dam" method
of lubrication is very effective for drilling in glass block
and is simple to use. Under water pan drilling works best
for bottles. "Pumping" the drill is also very
important since even under water, the tip of the bit will go
dry after drilling about 1/8" deep. Water lubrication
techniques are discussed in more detail in the Lubrication Tips & Tricks section.
Glass block normally has a vacuum
inside. Some of the water and glass dust will always be
sucked inside when the hole breaks through. However, it
is easy to rinse out the inside of the block with water as long
as the dirty water inside is not allowed to dry out. The
plug from the hole will sometimes be pulled into the block -
it will usually drop out easily when the inside is rinsed.
However, if too much pressure was placed on the drill as the
hole breaks through, it can cause the plug to have a flair from
the splintering on the rear of the hole. Normally, you
can remove the plug with a pair of needle nose pliers, but the
best solution is to reduce the drill pressure when nearing the
back of the glass to avoid splintering as the drill breaks through.
A Few Final Glass
Light Block & Bottle Tips
A piece of wire from a regular
coat hanger or a small wooden dowel work great for inserting
into the hole to "push" the lights around inside the
block, so that all the corners are filled with lights.
A hand drill works fine using
a starting template and a clay dam - for a few glass blocks.
However, an inexpensive drill press is well worth the cost if
you are making lots of blocks. There are many very nice,
inexpensive drill presses available these days and they make
glass block drilling fast and easy compared to a hand drill.
The most popular diamond drill
bit for glass block drilling seems to be the 1/2" size since
it is about the right size for light strings. We prefer
a 5/8" sized bit because the slightly larger hole gives
a little extra room when inserting the lights or when pushing
them around and allows easy remove of the lights if you change
your mind or need to change a bulb.
Glass blocks sometimes have a
white or cream paint coating around the outside edge to give
better adhesion for building mortar or caulk. Most people
remove the paint, but some just hide it under a ribbon.
If the paint is hard to remove, soaking the block in hot water
usually softens the paint and allows easy removal with a common
kitchen dish scratcher.
Glass blocks come in many sizes, shapes and surface textures.
The ones with a heavy surface textures tend to work best since
they diffuse the light and hide the light string wires better.
Our research has shown that there are at least 15 different surface
textures available (there are probably far more), so a little
searching can result in finding some unusual patterns that make
very nice light blocks. Most people seem to use the standard
8"x8"x3" blocks, maybe because they are easily
available. We have found that the smaller 6"x6"x3"
blocks and even some of the odd shaped triangular, brick shaped
and corner blocks are are also especially nice because of their
unique sizes and shapes. There are no limits to the artistic
possibilities, so don't be afraid to try something different.
A hot glue gun with clear glue
works very well to attach ribbons and bows, or ribbons can be
tied as if you were wrapping a package. Most people
tend to start out with the multi-colored lights then quickly
learn that the white and single colored lights are also beautiful.
The non-multi colored lights are especially nice for light blocks
that can be used all year round. Light strings also come
with various colored wire, so experiment with the white lights
with white wire or the red lights with red wire, etc to see what
Finally, if you ever get a chance
to try the "LED" or "Tiny Lights", give them
a try - especially the big strings of 60 or 100 (it takes a few
more lights because they are so small). Yes, they cost
more, but they create almost no heat and bulbs last nearly forever.
Most importantly, some LED light strings have a light function
controller that gives a special random blinking pattern that
blinks, twinkles and strobes, etc. If you can find the
type with the light controller, the LED strings with the special
lighting affect is really worth the additional cost. Our
experience is that most people who try the LED lights with the
controllers rarely go back to the standard bulb lights.