Hard Solder

As used for brazing, hard solder is generally a copper/zinc or copper/silver alloy, and melts at higher temperatures than tin/lead compositions.

In silversmithing or jewelry making, special hard solders are used that will pass assay. They contain a high proportion of the metal being soldered and lead is not used in these alloys. These solders also come in a variety of hardnesses, known as 'enamelling', 'hard', 'medium' and 'easy'. Enamelling solder has a high melting point, close to that of the material itself, to prevent the joint desoldering during firing in the enamelling process. The remaining solder types are used in decreasing order of hardness during the process of making an item, to prevent a previously soldered seam or joint desoldering while soldering a new joint. Easy solder is also often used for repair work for the same reason. Flux or rouge is also used to prevent joints desoldering.

Liquid Flux Use

Liquid Flux

It is important to put the minimum amount of liquid solder on the copperfoil seams. A surplus of liquid flux will bubble and splatter, leaving holes in the solder bead. Cutting your flux brush about in half, at a slight angle will reduce the amount of flux on your brush and ease the application.

Pour a small amount of flux, just enough for the task at hand, into a small container. Don't pour the leftovers back into the flux jar, it will contaminate the rest. Do not use the lid of your current flux jar, as it should be sealed at all times so it won't become sticky by evaporating.

When finished soldering, wash off the flux by washing it with warm water and a very little dish washing liquid and a soft sponge, then rinse with water. Clean your flux off right away after you finish soldering. Flux will oxidize your solder seams if left over time. It also becomes more difficult to remove when it has begun to dry.


See also:
Flux, an introduction
Fluxes, a description
The Purpose of flux
The action of fluxes
Soldering fluxes

Combination Grozing/Breaking Pliers

Description
The jaws of grozers are serrated and used to gently remove small pieces of glass which remain after the glass has been scored and broken. They are normally supplied with one straight jaw and one curved making them combination grozing and breaking pliers.

Use as breaking pliers
When used as breaking pliers the flat side should be up and the nose of the jaws almost touching the score line. The breaking pressure should be down and slightly to the side to bend and pull the piece away from the main piece of glass.

Use as grozers
When used a grozers – to gently wear away some small part of glass - the curved jaw should be up. The plier jaws should be used slightly open, and a downward motion of the plier does a “rasping” of the glass edges, taking away small bits of glass. With experience, a lot of glass can be removed quickly shaping the glass with a fair degree of precision. The edge can then be tidied by a grinder if required.

Waxing up Recipe

Beeswax alone isn't good for waxing up glass pieces on a glass easel, but combining it with Venice Turpentine makes a secure fixing material.

Recipe
250gm block of beeswax
2 teaspoons of Venice Turpentine

Method
Bring the two elements just to a simmer, stir it well and cool.

This produces a tacky material that when warmed in the hand sticks to the glass and the easel. When it cools it sticks firmly.

Use a palette knife to loosen the wax from the easel.

Hanging Panels - Hooks

If you wish to attach hooks to the panel so that the appropriate chain length for its setting can be attached later, you need to use brass or other strong metal that can be securely attached to the frame of the panel.

An easy solution is to use brass chain links. Cut one link from a suitably heavy chain at the centre of the long side of the link. Straighten one part of the opened link with two pair of pliers or a vice and pliers. Solder the straight leg with the open part of the hook facing outwards, to avoid the chain (which is pulling inwards) from slipping out of the hook. The open part of the hook should give only enough room for the chain links to be inserted between the frame and the opening of the hook

Hanging Panels – Chain, Wire, Line

The choice of hanging material is both aesthetic and practical.

Whatever material is chosen must be strong enough to support the panel over a long time.

Chain is reliable and can be obtained in many sizes, styles and metals. You can use a split ring to join the chain to the loops on a panel, or directly if the panel has been fitted with hooks.

Twisted picture wire is a reliable material too. It normally is twisted brass with at least one steel strand embedded. It can be soldered at various points around the panel and at the place where the eye if formed to insure that the twists will not come undone.

Fishing line can be used. You should use the highest test you can find. 50 pound test is sufficient but still not obtrusive. However, it is subject to deterioration with constant light exposure, and so should be renewed every 4-5 years. Also you need to be careful in the knots you use. It is very slippery and a surgeon’s know should be topped up with a second for security.

Fine cable enclosed in plastic can also be used. This is fine enough that it can be tied, but should be joined with knots that cannot slip.

Refining Edges

You can make the freshly cut glass safer to handle by gently wiping the edges of the cut piece with the waste piece. This removes the sharpest edges without chipping the glass.

After the glass is scored and broken, you can remove small, unwanted chips with grozing pliers. The serrated jaws of these pliers are used to gently nibble away at the jagged edges.

Rough edges can also be smoothed with a carborundum stone. You rub the stone along each edge, upper and lower, to remove any sharp edges. You can remove more glass with the stone if you wish by a little more aggressive grinding action or just a longer light rubbing of the stone against the edges.

A diamond smoothing pad removes glass in much the same way as a carborundum stone, but does it more quickly with the coarser grades. You can use a number of grades to get an almost bright polish to the edges. These pads must be used with water.

A glass grinder is used by many people. Many models of grinders are available. The grinding surface of the bit is covered with fine diamonds, which grind away unwanted glass very quickly without chipping the edges. In addition, they are water-fed which keeps the glass from cracking due to heat, prolonging the life of the diamond bit, and preventing the powdery ground glass form flying around.

A glass grinder is not a substitute for accurate cutting.

Silhouettes in Leaded Glass

There are also times when you may want to have a silhouette, you can cut it out of lead foil and solder it into place. This allows intricate shapes to be made when a dark representation of the shape is required. If the panel can be seen from both sides, the overlays should also be on both sides. This can be applied to copper foil too.

Representing Acute Angles in Leaded Glass

False lines are used in leaded glass where the design calls for an angle that cannot be cut into the glass. This includes right angles and even more acute angles. E.g., the petals of a fuschia flower. The design would call for an angle of about 60 degrees. This is impossible to achieve through cutting. So the glass is cut in a curve and the cames on the side and bottom of the petal have their hearts cut out so they overlap each other. The overlap is then trimmed to the shape of the outside of the petal. When soldered, the appearance is of the glass being cut at the angle required for the flower.

Dams for Drilling

For those who find putty or plasticene too insecure, it is possible to use a plastic bottle with the bottom and top cut off, and secured with hot glue. This will provide a non-slip dam for the water while drilling.

Glass Painting Tools

The tools needed for glass painting are few and relatively common, although the blender is specialised. The minimum you need are:

Glass palette –
A slightly etched glass sheet on which to grind and mix the paints

Palette knife –
A paint knife with a flexible metal blade used to mix and pile the paint

Tracing brush –
A thin and long-haired brush used to apply paint to glass. Sable is considered superior, as it can hold a lot of paint allowing long lines.

Badger blender –
A wide and flat brush made of badger hair used to blend or evenly disperse a layer of paint on the glass, or to stipple a fine layer for a pin-hole effect

Stippler –
A round, thick brush used to apply wet paint and create a stippled matt

Soldering Irons and Rheostats

People often want to have variable temperatures for decorative soldering.

It is often recommended to use a rheostat in circumstances where the soldering iron does not have an internal temperature control. The rheostat reduces the current reaching the iron. The degree to which you have to do this is related to the speed or amount of work you are doing with the iron. With reduced current, the iron can not build up to its previous temperature so quickly. Therefore, it is a matter of individual practice on the rheostat setting you use.

Temperature controlled soldering irons attempt to maintain a set temperature. This is controlled by the combination of the microchip in the iron and the tip. So to adjust your temperature all you need is a few different tips. For example, a number 7 tip lets your iron heat to 700F degrees. For decorative soldering your need tips of lower temperatures, usually a number 6 or 600F degree is enough of a reduction for most decorative stuff. A number 8 tip (800F) will let you work at a higher temperature if you work quickly.

You can buy an iron (not temperature controlled) and a rheostat but buying tips for the temperature controlled iron is cheaper. A rheostat is NOT a temperature controller. A rheostat actually reduces the power supplied to the iron, thereby making it take longer to heat or re-heat after a period of soldering. Many people advise that using a temperature controlled iron with a rheostat can damage the thermostat. Using an iron without a rheostat, provided you work relatively quickly, you will probably be able to solder all the joints in a small or medium panel without stopping to let the iron 'catch up'. In this case the temperature is controlled by the heating power of the iron balanced by the cooling effect of making the soldered joints.

With a temperature-controlled iron, if it is left idle, it will quickly reach its maximum operating temperature - just as quickly as an uncontrolled iron of the same power. When you start soldering, the cooling effect will trigger the temperature controller to provide full power until the operating temperature is reached again. Using an iron with a rheostat, you will need to slow down a little if you are to do that same panel without stopping to let the iron re-heat. In this case the temperature of the iron is controlled by the (reduced) heating power of the iron balanced by the same cooling effect of making the soldered joints.

Without a rheostat, if an iron is left idle, it will eventually reach its maximum temperature. This is usually too hot for soldering lead, but OK for joining other metals. With a rheostat, if an iron is left idle with the rheostat set to (say) '6', it will still reach its maximum temperature but very much slower than the one without a rheostat.The big advantage of the temperature-controlled iron is that you know it will never get too hot for the work you are doing, and that it truly provides that 100 watts (or whatever) power to keep it hot even when you are soldering at top speed.

Soldering Irons

GeneralHistorically soldering tips were copper, placed in braziers. One tip was used, when the heat had transferred from the tip to the solder (and depleted the heat reserve) it was placed back in the brazier of charcoal and the next tip was used.

Much later gas irons were in common use. These used a gas jet to heat the soldering bolt/tip. They are very fast, but require significant amounts of experience to properly regulate the temperature.

Currently, electric soldering irons are used; they consist of coil or ceramic heating elements, which retain heat differently, and warm up the mass differently, internal or external rheostats, and different power ratings - which change how long a bead can be run.

SelectionThe soldering iron used must be of a high enough wattage to readily melt the solder and be able to reheat fast enough to maintain the necessary melting temperature. The tip can't be so small it can't maintain the heat and not so big it covers more area than wanted.

For soldering leaded panels a 100w iron with a 3/8" temperature controlled tip that maintains a constant 370°C (700° F) is suitable.

For copper foil a higher temperature controlled tip is used. This normally runs at 425°C (800°F). Sometimes a tip of ¼” is used where more delicate beads are being run.

If a lot of soldering is required that has sustained heat requirements, you might consider a 200W iron. These can deliver heat more quickly and evenly than those with lesser wattage.

Silver Stain as a Colour Modifier

Silver stain can also serve a useful purpose to modify the colours of glass. If you add a silver stain pattern to a piece of light blue glass, for example, the result will be a green pattern. This creates all sorts of creative opportunities, particularly when used in conjunction with etched flash glass.

It is also possible to use the silver stain successfully with other paint and enamel colours to warm the colours.

Silver Stains - Mending Mistakes

If the stain did not take, there are techniques to try and improve the colour.

One is firing the silver stain face down on a sifted and smoothed out bed of whiting or thick ceramic fiber paper.

Another is to re-apply your stain and fire again between 675°C (1250°F) and 760°C (1400° F). The higher heat will help the silver stain "take" to the glass. Fire the silver stain face down because the higher temperature will melt the high fire tracery and matting resulting in kiln-wash sticking to the painting.

A third method is to use hydroflouric acid to remove the stain and so start again with clear glass. Remember this is an extremely dangerous chemical.

After a second successful firing, be sure to discard the loose whiting or shelf paper from your kiln-shelf as any residual silver stain absorbed during the firing can result in yellow spotting on your glass on later firings.

Firing and Cleaning Silver Stain

After the silver stain has completely dried, the glass is ready to fire in the kiln. Remember to fire silver stained items separately from other painted glass. The maturing temperature is between 509°C (950°F) and 565°C (1050° F). Place the glass on the kiln shelf with the painted side down and the silver stain facing up. Fire between 509°C (950°F) and 537°C (1000° F) for softer glasses, and to between 537°C (1000° F) and 565°C (1050° F) for harder glasses. The higher temperatures in each range will result in darker colour.

After firing and cooling remove your glass from the kiln. The glass will look exactly as it did when you first placed it in the kiln, as though it hasn't fired. In fact, the firing process will have done its job, but first you must remove the residual layer of gamboge gum. Simply spray with window cleaner and wipe off. Underneath, your glass should be stained some lovely shade of golden yellow.

Hanging Panels – Perimeter Wire

Often it is most secure to have the bottom of the panel supported, rather than relying on attaching hooks or loops to the edges of the panel.Panels with “H” lead came are the easiest and neatest to form a wire around. You can use twisted brass picture wire (which has a steel strand embedded) for this purpose or solid copper wire. When using picture wire, form a loop at one end by twisting the strands. In this example I am using solid copper wire.

Make a loop as described.


Open the leaves of the came at the top and solder the wire with the loop to the heart of the came. Use as little solder as possible and keep it away from the leaves, as solder on the leaves makes folding the leaves back very difficult.

Continue the wire around the side. Pull the wire tight and tack solder the wire at the bottom of the side. Continue the wire around the bottom and do the same at the other side.

Pull the wire tight to the top of the panel. Bend the wire over at the height you wish the loop to appear above the panel. Twist or bend the wire and solder it to the side of the came’s heart.

Close the flanges of the came over the wire and you have a neat finish to the edges.

You can, of course, decide to hang the panel from the wire going around the panel. In this case you eliminate the loop forming at each side of the panel’s top. I solder the wire ends together at the bottom, in addition to soldering the wire to the came at each corner. This provides me with the certainty that the wire will not come loose.

This can also be used to provide the hanging supports when placing the panel in a wooden frame. It takes the strain off the frame but still provides firm support of the panel.

Applying Silver Stains

Introduction
Contrary to its name, silver stain actually stains the glass yellow. Silver stain is available in shades from pale yellow to deep orange. Today the use of silver stain remains a popular choice for the glass painter with no other pigment matching its delicacy and wholly translucent quality. Silver stain is composed of silver nitrate and gamboge gum, a resin from Southeast Asian trees. It is sold in powdered form and is mixed only with water. A separate set of tools is required for silver stains as the stain itself is terribly corrosive to brushes and other tools.

Application
To use, the artist mixes the powdered stain on a glass palette to a thin consistency. This can either be applied thinly in a free-hand manner to the back side of the glass painting, or applied and quickly blended to smoothness with a badger blender for a more even result. Always apply the silver stain to the back side of the glass - in other words, the opposite side from the one that bears the tracery and matting you have previously completed. There are several reasons for this, but the primary one is that the silver stain will metallise the black and brown paint work during firing if applied to the same side. This metallising results in a strong bluish and opaque haze on the tracing and matting.

During application, be sure to work rapidly and evenly, finishing before the wet stain has a chance to completely dry. Also remove the excess stain while the stain is still damp. Scraping off the run-over will prove to be quite a challenge if you let it dry. When you have completed these steps, immediately wash your tools.

Tempered or Toughened Glass

Toughened or tempered glass is a type of safety glass that has increased strength and will usually shatter in small, irregular pieces when broken. It is used when strength, thermal resistance and safety are important considerations.

Toughened glass is made from annealed glass by a thermal tempering process. The glass is placed onto a roller table, taking it through a furnace which heats it to above its annealing point. The glass is then rapidly cooled with forced draughts of air to below its annealing point, causing it to harden and contract, while the inner portion of the glass remains free to flow for a short time. The final contraction of the inner layer induces compressive stresses in the surface of the glass balanced by tensile stresses in the body of the glass.

It is this compressive stress that gives the toughened glass an increased strength - typically four to six times the strength of annealed glass. The pattern of cooling during the process can be revealed by observing the glass with polarised light, which shows the strain pattern in the glass.

See also Prince Rupert's Drops

Soldering 3-D Pieces

When soldering 3-D pieces together, first tack the panels together with a single tack at each end. If it later turns out that there is an alignment problem, it is much easier to dis-assemble a few tacks, with a piece of paper inserted into the space between the pieces of glass and moved up into the molten solder while your iron is at the tack joint. The paper will strong enough to move through the solder, separating the two piece of glass.

Once your 3-D piece is tacked together and looks OK, turn the piece over on its side, and, using 50/50 or 60/40 solder, fill in the inner seams, moving the piece around. Be careful to support the piece with boxes or blocks and by holding it at the top part above where you are soldering, to prevent the piece collapsing.

Once the inside of the piece, say a panel lamp, has been soldered smoothly with 50/50, turn the lamp over. Get a few boxes or similar supports to prop the lamp up against, and make it so that there will be a level solder seam. Using the 50/50 solder again, fill in the seam. It doesn't have to be perfect, at first. Do all of the seam filling first, to ensure the stability of the piece. Then go back with 60/40 solder and, again making sure the lamp seams are level, finish by smoothly soldering each seam.

Perimeter Foils

Foil pulling away from the glass on perimeter

If this is happening to you, there are several things to remember.

Clean all the edges and surfaces just before foiling. This ensures there are no oils to interfere with the contact adhesive of the foil. Avoid hand creams just before foiling as this increases the amount of oils getting onto the glass.

Remember that lots of heat breaks down the adhesive. So do not remain in one place too long. However the adhesive is not the element that keeps the foil attached to the glass in the long term. Instead, think about whether the bead on the edge is thick enough to provide the rigidity required without relying on the adhesive of the foil.

Finally, think about whether an edging came would provide better support and finish to the piece.

Media for Glass Enamels and Paints

Mixing agents
These are the carriers that give "tooth" to the paints and are water-based or oil-based.

Common water-based media are:
· water & gum arabic,
· wine,
· sugar water,
· vinegar

Common oil-based media are:
· clove oil,
· lavender oil,
· damar varnish

Gum arabic
This natural gum (also called gum acacia) is a substance that is taken from two sub-Saharan species of the acacia tree, Acacia senegal and Acacia seyal. It is used primarily in the food industry as a stabliser, but has had more varied uses in the past, including viscosity control in inks. For artists it is the traditional binder used in watercolour paint. It is sold in powder and liquid forms.

Dammar gum
This is obtained from the Dipterocarpaceae family of trees in India and East Asia, principally those of the genera Shorea, Balanocarpus, or Hopea. Most dammar gum is produced by tapping trees, however some is collected in fossilised form from the ground. The gum varies in colour from clear to pale yellow, while the fossilised form is grey-brown. It is used in foods, as a glazing agent, and in the making of incense, varnishing and in other processes. Dammar was first introduced as a picture varnish in 1826 and is commonly referred to as Damar varnish.

Lead Came

Lead came is often just called came. There are two basic types of lead: hard lead and soft lead.

Soft lead is 100% pure lead with nothing added. Soft lead strips need to be straightened in order to remove the propensity to stretch and sag. The advantage of soft lead is being easier to bend and shape to curves and that straightening removes any kinks in the length. Within 50 years it will need to be replaced.

Hard lead has antimony added which stiffens the lead. This results in a stronger finished panel. However this kind of lead deteriorates relatively rapidly. The advantage of hard lead is the added strength and not having to stretch it. It will need to be straightened just before use though. It is still malleable enough to conform to most curves.

Came is available in many shapes, although H, U and C are the most common. The lengths are usually about 2 meters (6 feet). C and U shaped lead is used on the outside of a panel. H shaped lead can be used on both the interior and edge of a panel.

The came’s top and bottom are the flanges and the width of the flange is the nominal size of the lead. These flanges can be flat (parallel surfaces) or rounded (a slight dome on each of the flanges). The central part of the came is called the heart, normally 1.2mm (1/16”) thick.

Lead Knife

Description
The lead knife is used to cut the lead cames. There are many kinds of lead knives on the market. They fall into two basic types – the curved blade and the straight blade.
This is a necessary tool because lead dikes can't achieve acutely angled cuts readily.

Use
The important things to remember are to lubricate the blade, to maintain the proper angle, and to keep the blade sharp.

The blade is lubricated by wiping it through beeswax. Beeswax is slightly sticky so it will adhere to the metal better than ordinary wax. This greatly increases the ease with which the knife will slip through the lead.

The proper angle is maintained by keeping the blade in a line between your eye, the handle, and the blade where it contacts the lead. To push the blade through the came, you need to wiggle the blade from side to side (for a straight edge) or to rock it (for a curved blade) as you apply downward pressure. Too much pressure in relation to the wiggling or rocking movement will cause the lead to be crushed. Too little movement, will make the cutting slow.

Additional use
The lead knife can also be useful in positioning the lead around the pieces of glass, usually by gently pushing on the heart of the lead.

Common Solder Compositions for Stained Glass

Common solders for stained glass are mixtures of tin and lead, respectively:

• 63/37: melts at 183°C (362°F)
• 60/40: melts between 183°C (362°F) and 188°C (376°F)
• 50/50: melts between 183°C (362°F) and 212°C (421°F)
• 40/60: melts between 183°C (362°F) and 234°C (454°F)
• lead-free solder (useful in jewellery, eating containers, and other environmental uses): melts between 118°C (245°F) and 220°C (428°F), depending on composition.

The 63/37 and 60/40 solders are most often used in copper foil work because of their smaller melting range. This allows the solder to set more quickly than the solders with higher lead content. They tend to give smoother beads also.

50/50 and 40/60 solders are more often used in leaded panel work. Their wider range of melting temperatures allows the solder to spread and become flat.