Foil

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Foil is an adhesive backed thin sheet of metal, for doing Foil Construction and widely used in 3D Soldered Art and Suncatcher sized works, though there is no limit to what can be made with it. Foil is almost exclusively made from bare copper that has a pressure sensitive adhesive applied to the back but any solderable and malleable metal could be used in its place. The adhesive isn't strictly required but not having it makes for a much more difficult time. It is most commonly available for purchase as a 36-yard roll of specified width and backing color e.g. 7/32" Black backed.

Foil is normally applied by centering it on the edge of the glass so that it overlaps onto the front and back faces evenly, then it is pushed down onto the faces and Burnished. There is almost no limit in the ways foil can be applied, Foil Overlay is a common example of alternative uses.

Foil has a shelf life! Sealed it will be fine for 3-6 years, but once opened foil will only last a few years before the adhesive dries out and it will no longer stick decently.

Foil Parameters

Foil has a few parameters that are important to consider when looking for a suitable material to use in glasswork.

Thickness

Thickness is important as the thicker the foil the stiffer it is and harder it is to wrap around complex geometry. Thicker foil is less prone to tearing at the edge as the material is stronger. Depending on the shape being foiled Foil Saddles might be required to get a complete foil line.

Width

Width controls how thick of a glass can be wrapped and how thick the resulting solder lines will be on the front and back of the finished work.

Backing Color

Backing color doesn't really mean much except in cases where the glass is Cathedral, Opalescents or Clear as the backing of the foil will show or reflect back into the glass. Though it doesn't have that large of an effect in the end, it mostly comes down to the makers preferences. For example, if a project uses clear/tinted glass and black Patina it may be preferable to use black-backed foil.

Normal Foil Parameters
Parameter Common Values
Thickness 1.00 or 1.25 Mills
Width 5/32, 3/16, 7/32, 1/4, 5/16, 3/8, 1/2 inch

(3, 4, 5.5, 6, 8, 10, 12.7mm)

Foil can also be found in sheets of various size.

Backing Color Black, Silver or Copper (without any backing color)

Common Issues

Problem Issue Solution
Foil does not stick to glass
  • Glass is dirty/oily.
  • Foil is old.
  • Clean the glass more thoroughly and avoid touching the edges.
  • Replace the foil.
Foil is tearing on curves
  • Foil is too thin
  • Foil is being pushed down too fast
  • If using 1.00 Mill foil or thinner, try thicker foil.
  • Reduce the rate that the foil is folded over the edge by doing multiple passes or use Foil Saddles
Foil is not taking solder
  • Foil is dirty
  • Foil is old
  • Flux was not adequately applied
  • Clean off any debris from the foil or cut out bad sections, like where the adhesive keeps the roll from unwinding.
  • Replace foil.
  • Apply more Flux and rub it around with the brush.

Tips

  • Storing your foil in an airtight bag/container can extend the life of it.
  • Binder clips can be used to help keep foil rolls from unwinding while not in use by clipping them over the roll.
  • Thread shears can be used to cut the foil faster and more reasonably than regular scissors.
  • Foil can easily be trimmed with any Craft Knife.
  • Sheet foil can be cut on most Cutting Machines.