Sal ammoniac is a naturally occurring ammonia salt that is used for "tinning", which means coating with solder. Some metals like copper can be tinned quite easily using just flux, while other metals like the steel jackets on soldering tips take a bit more coercing. That's where the sal ammoniac comes in. The sal ammoniac tinning block has the ability to clean the tip better than flux can so that solder will easily adhere to it.
You need to use a fully heated iron tip, which will cause sal ammoniac to "sublime", which means to go straight from the solid white block and turn into a gas, in this case a choking white ammonia smoke. (So it is best to tin your iron with active ventilation.) Just add solder while rubbing all surfaces of the tip firmly on the block. When all surfaces are nice and shiny quickly turn the iron temperature down before you burn off the nice new tinning job!

Now here's something I learned from a real old timer I worked for twenty years ago. You can break off a chunk from a sal ammoniac block and dissolve it to make sal ammoniac water. (About two or three tablespoons full to a cup of water.)
As you work if you see the bright shine of your clean tip begin to dull a quick dip (actually more of a jab) into the sal ammoniac water cup will quickly restore the shine without causing the corrosive fumes that using flux would.
It is important to learn the correct technique for this. The iron tip must enter and exit the water as quickly as possible without getting the iron barrel into the water. If done properly you will hear a sharp "KISSing" noise as a thermal shock breaks all of the oxides off of your tip and they fall to the bottom of the cup. If you do it too slowly the junk will not break off and your iron will be over-cooled so you will have to wait to resume your work.
When the cup fills up with junk in a few months, throw it away and start over. Sometimes the salt tries to escape. If it starts to crawl out of the cup, just scrape it back in.

Find Sal-ammoniac Here! (Click on Chemicals on the menu at left.)

11/96 Organizing Scrap Glass

Our thanks to Avis Ann Rosenlund for our November tip of the month!

"I keep my small pieces of 'leftover' glass in a file box that is normally used for tax records. It is divided and a solid, durable container that allows you to keep the pieces sorted by general color. i.e. reds, yellows, blues, browns, etc. that you can label on the top of each divider. If you have lots of 'leftover' glass you can use separate boxes for each color and label these. I also find this helps me in going through the glass to find the right piece as it is standing on edge instead of laying flat in a 'junk glass' box. It helps in preventing cut fingers by pawing through the box and also helps in preventing scratches from one piece to another. Helps me.....hope it can help someone else! Avis Ann Rosenlund"

10/96 Fixing Foil Splits

Last month we talked about how to prevent foil splits while foiling, but there will still be times when your foil will split and you either don't notice it until the piece is soldered in, or the curve you are foiling is so extreme that you just can't avoid it. Now you need the cure!

Case one: You have just foiled the piece and are aware of a small split and are fairly sure that any attempt to re-foil the piece will just split again.

In this situation the easiest fix is to wrap copper foil around your piece covering the split, then trim the excess foil even (front and back) using an exacto knife.

Case two: You are soldering the panel and you notice a split in the foil before it gets soldered over but too late to remove the piece.

Thoroughly clean off ALL of the flux from the split area and press foil firmly over the split. Apply a bit of flux and tack the foil lightly in place then trim it even with an exacto knife. Now you can solder the foil down neatly but take care not to heat it too much or rake the iron across the foil because the heat softens the adhesive and the foil may float out of place.

Case three: You have soldered over a split and it shows in the soldered line.

If the split is extreme, you will have to remove some solder and follow the fix in case two above. If on the other hand the solder came close to bridging the gap but did not quite make it use an exacto knife to trim across the points of the foil that stick out. Then re-solder that bit of your line and the crack will disappear.

9/96 Preventing Foil Splits

If you work with copper foil you have probably already had to deal with the problem of cracked or split foil.

What makes foil split and what can you do about it?

If you think back, you will see that just about every time you have had a split in your foil it occurred in the foil of an inside curve.

When you fold the foil down along a straight line it is like folding a sheet of paper in half. It just folds and lays nice and flat. On the other hand, you can't even fold paper in a curve. This is because if you fold something around a curve one side must become longer than the other.

Look at the illustration of the two concentric circles. You know immediately that the line around circle "A" is longer than the circle around circle "B". If you imagine that the orange area represents copper foil wrapped around the edge and folded into the center you will see that the foil has gone from a larger circumference to a smaller one. If you have foiled tight circles or curves you know that this is accomplished by allowing puckers to form (taking up the extra length) and pressing them flat.

Finally consider the half circle piece illustrated. Around the outer curve the foil will have excess length when folded over and you can just crimp it down flat, but the inner curve is just the opposite. After you lay your foil on the edge it has to get longer in order to fold down flat.

The Solution?

Fortunately copper is a malleable metal and will stretch considerably with a little help from you!

First, avoid using the light weight foils on tight inside curves. The thinner the foil the less it can stretch without ripping. (Use .0015 AKA 1.5 mil foil.)

Second, never attempt to just fold the foil of an inside curve flat in one movement, it will rip every time. You must fold it gradually. I use my burnishing tool to fold the foil in stages, gradually stretching it.

Next Month: Fixes for splits. (After the fact)

8/96 Adjusting Fit

When adjusting the fit of your panels use the cartoon as a guide to finding the suspected misfits but never start to adjust a piece of glass until you have compared it to the pattern used to cut the piece. Since patterns are made from tracings of the cartoon and and the glass is cut from the pattern, not the cartoon, variations in the tracing can lead you to adjust the wrong pieces and make matters worse!
It is like a game of "telephone", where players whisper a message to one another and by the time the last player gets the message it has changed completely. In each "generation" the shape of each piece changes slightly.

If you can't even get a hint of where the problem is from the cartoon you can just compare the pieces to the patterns one at a time until you find the problems. Remember that if you did not cut your pattern with a pattern shear or double bladed knife the glass should be slightly smaller than the pattern all the way around. This extra space is necessary to allow for copper foil between the pieces of glass, room for solder to flow between the glass pieces for strength and to allow for slight irregularities in the cut edge.

A properly fit panel will have wiggle room before it is foiled. If you slide your hand across the pieces in an assembly jig you will hear a clickety click as the pieces shift against one another. Most of this room will be taken up after the panel is foiled.

7/96 Try Cutting Glass on a Plexiglass Surface

My favorite surface for cutting glass is ordinary plexiglass plastic sheet in either 1/8" or 1/4" thickness. Working on plexiglass I can move the glass as I cut it enabling me to score any curve or circle without lifting the glass cutter. In fact, when I score a circle I draw the cutter in a straight line toward me and rotate the glass.

You can then "open" the score line all the way around the circle(1) before adding "relief score lines"(2) to help remove the scrap from around the circle.

1) 2)

The resulting circle is much cleaner than those cut using traditional methods.

6/96 Straight Cutting Against a Ruler

Why do I have trouble cutting a straight line using a ruler?
This is truly one of the most frequently asked questions from new students at our studio. It looks like it should be the easiest thing to do. You don't even have to guide the cutter, the ruler does it, right? Yet time after time you score the glass and it breaks wrong. --- What's happening?

There are a lot of different factors that can lead to failure in doing good ruler cuts.

The first one is equipment. The ruler you use should be at least 1/8" thick with a non-slip backing. Otherwise your cutter may tend to run up onto the edge of the ruler and your score will not be effective. (You can add self adhesive cork, or even a few layers of masking tape to make your own non-slip backing.)
The glass cutter is also a factor. While I prefer one of those "newfangled" cutters for most of my work, I still prefer the old-fashioned standard cutter with teeth on the head for cutting against a ruler.

The second factor to be considered is the sheer complexity of the task. What at first appears simple, when analyzed, is much more complicated. Your concentration must be split between your right and left hands. Believe it or not holding a ruler requires attention. It must be held absolutely still which requires even pressure applied to both ends and the middle simultaneously. Add to this, keeping the hand holding the ruler out of the way of the traveling cutter.
Attending to these new tasks can distract you from making a proper score.

Finally there is the score itself. While the ruler may control the direction in which the cutter travels, it can't insure that the cutter is not slightly twisted, in which case you will produce a scratch on the glass rather than a score line!
To make it easier to track true with the cutter, I hold it differently for ruler cutting, very similar to holding a pen. (Reverse these instructions if you are left handed.) I hold it with my thumb on the left side (around the middle of the cutter), my pointer finger resting in the curve on the back of the cutter, and my middle finger extended to press against the right side of the cutter head. With the middle finger I apply pressure to ensure that the cutter travels absolutely straight against the side of the ruler.
To give myself every advantage I tilt the cutter to produce caster.You may have heard of caster when you had your car's front end aligned. In short it is the effect that causes the front wheels of a shopping cart to always find the straight position. If you tilt your cutter as illustrated, you will produce caster and the cutter will tend to travel in straight lines.
missing illustration
In the illustration above the ruler is not shown. It would be located across the bottom of the screen, closer to you than the glass cutter.

NOTE: Perhaps most important in sucessful ruler cutting is getting a chance to practice on scrap window glass until you can do it with confidence!

5/96

Preventing Solder Run Throughs

Our thanks to Richard Cole for our May tip!

When soldering the back of a foiled panel we always try not to damage the smooth soldered lines that we worked so hard on, on the front. To avoid this, I wet a terrycloth towel, ring it out so that its not dripping and flatten it out either full or folded, depending on the size of the piece, but always as flat as possible for the best contact. Don't worry about cracking the glass since the glass and wet towel heat up together at same time, there is NO sudden temperature change so the glass will not crack. I do every panel with this towel method, and believe me it helps!!!!!

4/96

Special Foil Applications

So you've got all your glass cut and are ready to foil your panel. You've decided to use 7/32" foil, a good choice, but before you just blindly begin wrapping your pieces take a look at your panel.

"Sometimes a solder line is just a solder line." (but not always)

Sometimes a solder line is a flower stem, a bicycle spoke, a ship's riggings or what have you! When it is, it deserves special attention.

A flower stem is not just the metal needed to hold your glass together. It is a design element. To make it look like a flower stem it must be wider than your other solder lines so that it will stand out. You can accomplish this by using a wider foil such as 1/4", or even 5/16".

missing illustration The illustration shows the narrower 7/32" foil overlapped by the wider 1/4" foil.

On the other side of things, in situations like bicycle spokes where you want to make those lines finer, apply a narrower foil such as 3/16" foil first. Let it wrap around the corners then apply the 7/32" foil starting right at the corners.

3/96

USE OF GLASS "GRAIN"

Most glasses whether opalescent (having an opaque white base color) or cathedral (any clear colored glass) have some kind of visual "grain". The outcome of your stained glass projects can be greatly enhanced by paying attention to and using this grain as an integral design element. Mark the grain direction that will best suggest the "flow" of a flowers' petals or the wings of a butterfly, right on your patterns before you cut them apart. When tracing your patterns onto the glass, just make sure the lines on the patterns are lined up with the lines on the glass sheet.

When making a border around a panel there seems to be a natural tendency to run the grain in long lines up the side of a panel. This is a holdover from our recollection of wooden frames but is generally not the best way to go in glass. If you run your grain the short way you will benefit in two ways.

	Short grain creates an exciting run of quick color changes up the side of the panel rather than the lazy look of long grain.
	When working with opalescent or streaky glass it can be difficult to find glass that matches to make an entire border. One strip may have a white stripe down it's length, the next no white at all. Short grain cuts across the varying parts of the sheet working all the variations in color into each strip for a more uniform looking border.

2/96

CHOOSING YOUR FOIL SIZE

Good copper foiling technique is just as important to your finished product as good cutting, but you have to know the fine points.

The foil you select will have a great effect on the appearance and strength of your product. We start out with 7/32" as the "default" size on any work under two feet in both width and height. (For larger panels it is necessary to assess the way the glass pieces mesh together. It may be necessary to step up to 1/4" foil for strength if the design has many long straight parallel lines.)

With 7/32" foil your products will not have the amateurish look 1/4" foil often creates, yet it is virtually as easy to apply and solder. 3/16" foil will give a finer line but is difficult to apply, is harder to solder neatly, may be structurally unsuitable for larger work and because the line is so narrow it tends to accentuate your cutting inaccuracies. Of course there are times when other sizes are needed for a special look, for example in a prairie style design, a wider foil looks better.

Tips Menu (with more tips from the archive)

sal1996 Stained Glass Workers' Tips, Archive

The Solution?

1) 2)