Foil Construction
Foil Construction or also commonly called Tiffany Method is a type of cold glass construction where individual glass pieces are wrapped with a thin metallic tape known as Foil. The result is then Soldered together. Invented in the late 1800's, the use of this method of construction was popularized by Louis Comfort Tiffany hence why this is commonly called "Tiffany Style" glass when being referred to regardless of the actual artistic style.
This page is just a general look at what foiling is, thus if you wish to learn more about a specific step or dive deeper into why, how and what to look out for check out the pages for each individual process.
Foil construction is a type of Leaded Glass assembly where individual pieces of Sheet Glass, glass elements or other non-glass objects are wrapped with Foil and then Soldered together. It's also known as Tiffany Method because of the large influences Louis Comfort Tiffany had by using the method. Commonly he is thought to have invented the process when he actually did not but was rather just a prolific and popular user.
Foil can also be used in many decorative uses like Foil Overlay and for attaching glass to things that otherwise can't be soldered to.
While many of these steps are shared with many other methods of glass construction foil requires a much more precise piece of glass to be shaped. Also as the connection material is attached to the glass separately and then formed in place it allows for much more complex work to be done that couldn't be otherwise achieved.
Differences between Came
One of the main differences between Came is the fact that you do not need to make sure you are capable of bending a large chunk of metal onto the shape of glass. With foil, there's no compromise to the size of the joint across the work due to the complexity of the part.
- Foil is easily used for Overlay.
- Parts can be very small.
- Joints are easily managed and can be easily modified by using different sizes of foil or by trimming the foil with a Craft Knife.
- Foil can't be weather proofed and is not water tight due to the adhesives.
- Finished works are often weaker and require more Reinforcing.
- Easily used for constructing 3D and other odd shapes.
Overview of Foil Construction
This method can be broken down into the following steps.
- Draft or pick a pattern
- Pick the glass
- Transfer the pattern
- Score and Break the glass
- (Optional) Grind the glass
- Wrap each piece of glass with Foil
- Burnish the Foil
- Solder the project together
- Wash the project
- (Optional) Apply finishes like patina, polish or wax.
Grinding glass for foil
While grinding the glass isn't required it can have some benefits!
- Rough, uneven edges do not foil easily and removing those bumps and chunks will allow you to stick the foil on easier.
- Adhesives stick to rough surfaces better, doing a single pass around the part will allow the adhesive to stick better.
- As you are directly working with the edge of the glass it can be helpful to do a quick pass on the grinder to remove the sharp edge. This also helps protect the foil from being cut during Burnishing.
Though if your glass isn't close enough to the pattern you will want to grind them closer. A major part of foil is that where the foil is placed is where your joints will be and they will look exactly like how the foil is placed! You will want to make sure that you have an even base for the foil to be attached to otherwise you will need to trim the foil to look correct.
Wrapping the glass with foil
When wrapping the foil onto the glass your ultimate goal is to try and center the glass on the foil so that the overlap on the front/back are the same. As glass comes in many thicknesses and Textures, foil also comes in multiple widths to accommodate these differences. Not only can these different thicknesses be used on thicker glass but they can be used to control the thickness of the resulting joint for artistic reasons! There's even multiple backing types to help make the foil blend into the finished solder. Regardless of foil type or object being wrapped you are going to follow the same steps.
- Pick a point to start the foil on the part trying to keep the end on the inside of two parts and not the edge. It can also be helpful to start a short section around a corner to help hold the foil in place while working as the adhesive isn't super strong.
- Slowly wrap around the glass while centering the glass on the foil. When you have long straight sections you can speed up the wrapping by lining up the whole edge at once.
- Once back to where you started, cut the Foil slightly longer so it overlaps the starting point. Trying to get it match exactly isn't really worthwhile and can result in holes forming as solder will not stick to glass.
Burnishing the foil
This is a mostly simple step! We are going to fold down the edges and make sure the Foil is smoothly stuck down to the glass. While you can generally do this in any order, this is probably one of the better ones for avoiding any issues or mistakes.
- Take your Fid or burnishing tool and rub down the edge you applied the foil to first. This will help anchor it in place and prevent it from slipping later on.
- Then start by picking the front or back and then a corner if there is one. Corners are special as the foil needs to fold over itself in a specific way or the adhesive will face up and we don't want that! You can see how it wants to naturally fold when looking at it.
- Fold the corner over so the adhesive side stays down, then continue down the edge and keep going around the whole part.
- If the part has a Concave side you will want to carefully roll the foil down across the section to reduce ripping.
- Repeat for the other side.
- Make sure that the foil is applied smoothly and doesn't have any foil sticking up, adhesive facing up or wrinkly anywhere. Creases are ok.
Soldering
Soldering foiled work is a little different than anything else as you are creating the bond between each part and how it will look. It can be a bit of a challenge at first to get it right, though don't worry about it too much! Solder can be reworked infinitely and if you can't see any copper while having a small heap of solder on there it will hold well enough.
There's tons of methods for how to solder a foil project so this is mostly up to you finding what you like to do but it can be beneficial to Tack Solder the whole thing before moving on. This will simply hold the project together and allow you to remove any pins or other things holding the loose glass parts together in the proper shape.