FOILING
DETERMINING WIDTH
Carol Conti: In order for the adhesive on the foil to “take”
to the glass when you foil, make sure your hands are clean and dry and
don’t use hand lotion. Also, make sure each piece of glass is clean
and dry. Copper foil is available in widths of 1/8” to 1/2”.
The width of foil should be matched to the thickness of the glass plus
an allowance of 1/32” or less for overlap on each side of the glass.
The most frequently used width for lamps is 3/16” however 5/32”
is used for slightly thinner glass and 7/32” for thicker glass.
Black-backed foil is used on glass (such as fracture glass) if there is
a possibility of the copper backing showing through.
Sue Gorden: The shade I am ready to foil is made of Oceana and Youghiogheny
glass. The instructions for this shade say to use 3/16” foil. Since
I already have a ton of 7/32” foil, could I use that instead and
use 3/16 on the smaller pieces so the lead lines are smaller?
John Cannon: You can certainly use the 7/32” foil on the glass pieces
and may choose to use the 3/16” on the smaller pieces. If you were
careful to cut and grind the glass and tried to minimize the spaces between
the glass pieces, the increase in foil widths between using 3/16 and 7/32
is a mere 1/64” on each side of each glass piece and on each side
of the gap between the pieces. I believe it is the skill used in cutting,
grinding and fitting all the foiled pieces together that contributes much
more to the finished look of a shade than the difference in using difference
widths of foil. The thickness of lines is really a matter of personal
preference, and like so many things in lamps, each person gets to make
his own choices.
Twyla Morgan: Many years ago, my first glass teacher taught us to try
to keep lead lines at one size on the outside of the shade. This meant,
in some areas, having more of an overlap on the back than on the front.
The width can also be controlled by the size of foil you use. If you have
more of a gap between pieces than you want, you can use a very narrow
foil as long as you have a little overlap on the glass. I keep several
widths available in my foil holder.
RESTORING ADHESIVENESS
Ross Lynch: Every once in a while I get a roll of foil that won’t
stick to the glass. Before I foil now, I preheat all the glass with a
small electric fan heater. This improves the bond between the foil and
glass and be very handy when you foil irregular-shaped pieces. It also
makes it a bit easier to trim back any excess foil later on.
Chaz Smith: To help restore the adhesiveness of foil, use the heat of
your light table to warm the pieces of glass that are to be foiled.
Joni Tornwall: While foiling my latest lamp, I discovered there were some
sections on the roll of foil that did not seem to stick. I tried burnishing
it really good and that seemed to work, but when it was time to solder,
it turned into a nightmare.
Vic Seeted: I’ve had the same problem with “non-sticking foil”
but I think the problem is with the glass and not with the foil. My solution
was to use sandpaper on the edge of any glass piece that I was having
trouble with and then the foil would stick much better.
Julie Stearns: I was taught by Larry Cartales to use isopropyl alcohol
on my glass pieces if the foil doesn’t want to stick.
Vic wrote back: I tried Julie’s hint on my latest project and it
does work! I just wipe those glass pieces with alcohol and it’s
almost like a magnet - the foil sticks to the glass like glue.
Mike Barnes “Just in case alcohol or other cleaning methods don't
help, I have used Tacky Wax on the back of foil in hard to stick areas
as was the case when I used extremely irregular Drapery. I use denatured
alcohol. It's made of ethyl and methyl (denaturant) so you get almost
100% alcohol with maximum evaporation. However, be sure to use it in a
well-ventilated area.”
Ernie Downey:You might consider an alcohol bath. Pour some alcohol into
a shallow pan and pass each piece through it as part of the final cleaning
process. If you have many pieces that the foil won’t adhere to,the
“bath” would eliminate the possibility of any problems.
Bob Tesch: Why does the alcohol help? Because it cleans the glass. When
foil won't stick, the first suspect is unclean glass. Just handling the
edges can put body oil on the glass that is not easy to see.
John Cannon: I agree with Bob. I suspect the non-sticking issue is directly
related to cleaning the glass properly. I’ve found that as you handle
the glass it warms slightly which also allows it to accept the foil better
than cold glass does. The age of the foil may also play a part in this,
but starting with clean glass and burnishing the foil edges against the
glass as foil is applied will go a long way in leaving good foil edges
until soldering can be finished. Another point is that the age of foil
will also play a role in flux not sticking to it if the foil has oxidized.
A light rubbing with fine steel wool will allow the flux to stick and
this will allow the solder to flow and stick to the foil. Without flux
and enough heat, the solder will not coat the foil, but will tend to bead
up on the surface and not adhere properly.
Bill Geller: One added suggestion while we're on the topic of foil: I
have found that old foil does not have great adhesive holding power, so
I wrap the foil in Seran-wrap or put it in a seal-type baggy - expelling
as much air as possible . This type of storage seems to keep the foil
fresh & tacky.”
Chaz Smith:My guess about foil not sticking is that there is moisture
on the glass. Glass stays cooler as the room warms up, and thus is a target
for condensation. The alcohol wipes away the condensation, and then evaporates
itself, leaving the glass dry so the foil sticks. Likewise, heating the
glass dries it which allows the foil to stick. 29
I used to work in at a place that dealt with optical devices. We never
used denatured alcohol on the glass, as it left a residue when drying.
Instead, we'd use pure grain alcohol that was purchased from a liquor
store.
DIFFERENCES IN ADHESIVENESS
Patti Curtin: It’s been my experience that black-backed copper foil
has the best adhesive.That’s followed by regular copper foil. Silver-backed
copper foil has the poorest quality of adhesiveness. So, if you need to
use silver-backed foil, try using the silver-backed silvered foil. The
adhesive is just as good as the black-backed copper foil. There is silver
on both sides of this foil, and it’s a little more expensive, but
it’s worth it in the right application. Personally, I use the black-backed
copper foil unless I’m foiling something very light in color, like
whites or yellows or pinks. The black-backed foil really does leave a
dark shadow, whereas the silver-backed silvered foil doesn’t.
PROTECT ROLLS OF FOIL
Hanka Nowakowski: To care for my unused rolls of foil, I wrap them in
plastic and keep them in an air-tight can with a lid.
PROCESS OF FOILING
Carol Conti: Center the glass on the foil leaving the same overhang on
either side. Wrap the foil around the entire glass piece, pressing it
to the edge with your fingers as you go. Overlap the foil about 1/8th
inch before cutting it off. For glass pieces along the rim or top edge
of the lamp, don’t start the foil along the exposed edge since it
might come loose during soldering or releasing. An inside curve should
be foiled starting at the deepest point of the curve. Start pressing the
foil down on one side of this piece and then carefully repeat on the opposite
side. This helps eliminate tearing the foil.
FOILING RIPPLE GLASS
Mike Barnes: Use 1/4” foil and trim the areas that look too wide
with an X-acto knife. Generally, I also use 3/16” foil, but when
the glass dictates, I’ve had to use 7/32”. Sometimes, when
the foil doesn’t cover the glass properly, I overlay another piece
of foil on that area.
Chaz Smith: I use the 7/32nd foil in 1.5 mill to wrap ripple glass. It
covers the high points. In the low points, I burnish the foil over past
90 degrees so that it folds down towards the glass. That makes the lead
line narrow again. If I come to a flatter area of glass, I trim off some
of the excess width. I find the thick foil is necessary, since the thinner
.001 or .00125 thicknesses tend to tear.
Carol Conti: You might want to cut your own foil strips from sheetfoil
to wrap heavy ripple or drapery pieces. I found that this method of making
individual strips for glass with unique thicknesses will save you time
and frustration in the long run. You could also use additional strips
of foil to achieve the required overlap on the “peaks and valleys”.
Make sure the back edge of this special glass is properly foiled.
FOILING JEWELS, GLOBS & MARBLES
Joan Bengston: It's easier to trim a strip of foil lengthwise with a scissors
while it still has the paper backing on it rather than fussing with an
X-acto knife. Most jewels have a thinner edge that you can fold the foil
around and it's just as stable as the glass. At times when using glass
globs or marbles (on flat panels) that have such broad edges, I grind
a shallow groove around the circumference where the foil is going to go.
I press the foil into the groove and make sure the solder flows down well
between the pieces. That holds it tight so you can't push it out. I put
the almost finished panel up on props before placing the globs or marbles
and then finish the soldering.
FOILING A “VALLEY”
Dick Watson: When foiling glass pieces with a sharp return or “valley”,
try starting your foil in the middle of the valley and allow your usual
overlay. Rather than trying to bend the foil down completely in one go,
gently stretch with several rubs.
BURNISHING
Carol Conti: Use a lathekin (dowls or wooden rollers also work) as a burnishing
tool to press the foil onto all edges. The foil must be pressed as flat
as possible so that no dirt or flux can leak under the foil causing later
problems with soldering or patinating. Always lay the foiled piece on
a clean, flat surface when burnishing.
BURNISHING SURFACE
S.B. Anthony: A computer mouse pad makes a great surface on which to foil
and burnish your glass pieces.
USE THE SEPARATING FEATURE ON YOUR FOIL DISPENSER
Joan Bengtson: As you feed a strip of foil through the opening of your
foil dispenser, take a second to separate the backing from the foil. Following
that, the dispenser will automatically peel off the backing as you work.”
HOLD YOUR DISPENSER IN PLACE
Jennifer Buckner: I use a foil dispenser, but found that it wanted to
slide off the edge of the table while I’m foiling. My solution was
to cut a little square of rubberized mesh shelf liner and put it under
the dispenser. Now, it stays in place.
ELIMINATE OXIDATION ON FOIL
Sandy Stringfellow: I’ve had no problems with oxidation. When I’ve
finished foiling a section of a lamp, I put Saran Wrap over that section
and then cover the whole mold with a big plastic garbage bag. (I don’t
know if the bag did any good, but it made me feel better.)
Joyce Mattson: If your foil is showing the effects of oxidation because
it hasn’t been covered with solder yet, use a piece of fine steel
wool dipped in flux and gently rub away the oxidized area before you continue
to solder.