Solder Touch-ups

Can you go back and solder again after cleaning if you realize a part needs touched up or to add jump rings?

Yes, it is possible.

There are some conditions, of course.

• Clean area back to the bare solder

• Use a small amount of paste flux to avoid lots of clean up of flux. Paste flux will stay pretty much where it is put and does not spread so much as liquid flux does.

• Apply the solder as usual for the area.

• Clean again as for the original soldering, but without metals.

• Rinse in cold water and dry.

• Add the patina immediately

• Polish as usual

Finished!

More complete discussion and information is here.

https://verrier-processes.blogspot.com/2025/11/patina.html

Is Zinc poisonous?

 

Compared to several other metal ions with similar chemical properties, zinc is relatively harmless. Only exposure to high doses has toxic effects, making acute zinc intoxication a rare event. 

Rather than being a toxic metal ion, zinc is an essential trace element. Whereas intoxication by excessive exposure is rare, zinc deficiency is widespread and has a detrimental impact on growth, neuronal development, and immunity, and in severe cases its consequences are lethal. Zinc deficiency caused by malnutrition and foods with low bioavailability, aging, certain diseases, or deregulated homeostasis [equilibrium] is a far more common risk to human health than intoxication.

The Essential Toxin: Impact of Zinc on Human Health, by Laura M. Plum, Lothar Rink, and Hajo Haase

Hazards of Flux Fumes

 

Note:  These health risks are those associated with industrial exposure – frequent and for extended periods.  They do not apply directly to occasional and shorter periods of exposure.

Risks are assessed as acute and chronic.  Acute means immediate reaction.  Chronic means the effects are cumulative and may take years to appear.
 

Composition of Flux

The major components of commercial flux are varying combinations and proportions of zinc chloride (or ammonium chloride), hydrochloric acid, phosphoric acid, citric acid, and hydrobromic acid.  It comes in many forms and many brand names.  It is important to use water soluble flux in stained glass work to enable thorough cleaning.
 
 

 

Zinc Chloride Risks

Zinc chloride inhalation from smoke screen generators or smoke bombs may cause transient cough, sore throat, hoarseness, a metallic taste, and chest pain.  Exposure to high zinc chloride concentrations produces a chemical pneumonitis with marked dyspnoea, a productive cough, fever, chest pain and cyanosis. Pneumothorax and the adult respiratory distress syndrome (ARDS) have been reported. Fatalities have occurred….
http://www.inchem.org/documents/ukpids/ukpids/ukpid86.htm#:~:text=Toxicity%20Zinc%20chloride%20is%20corrosive,anorexia%2C%20fatigue%20and%20weight%20loss.
 

Ammonium Chloride Risks

Exposure to Ammonium Chloride is moderately hazardous, causing irritation, shortness of breath, cough, nausea, and headache. Most exposure is a result of contact with the fume form of this chemical (Ammonium Muriate Fume and Sal Ammoniac Fume), which is a finely divided particulate dispersed in the air. The fumes are capable of causing severe eye irritation. Consistent exposure can cause an asthma-like allergy or affect kidney function.
 
In the event of accidental contact, get immediate medical attention and follow these first aid measures:
·        Skin Contact: Immediately flush skin with water and disinfectant soap and use an emollient on irritated area.
·        Eye Contact: Rinse eye(s) with water for at least 15-20 minutes. Protect unexposed eye.
·        Ingestion: Rinse mouth thoroughly with water. Do NOT induce vomiting.
·        Inhalation: Move to fresh air and administer artificial respiration if needed.
https://www.msdsonline.com/2017/05/05/chemical-spotlight-ammonium-chloride/#:~:text=Exposure%20to%20Ammonium%20Chloride%20is,particulate%20dispersed%20in%20the%20air.
 
 

Hydrochloric Acid Risks

Hydrochloric acid is corrosive to the eyes, skin, and mucous membranes.  Acute (short-term) inhalation exposure may cause eye, nose, and respiratory tract irritation and inflammation and pulmonary edema in humans.  Acute oral exposure may cause corrosion of the mucous membranes, oesophagus, and stomach and dermal contact may produce severe burns, ulceration, and scarring in humans.
 

Acute Effects: 

Hydrochloric acid is corrosive to the eyes, skin, and mucous membranes.  Acute inhalation exposure may cause coughing, hoarseness, inflammation and ulceration of the respiratory tract, chest pain, and pulmonary edema in humans.  Acute oral exposure may cause corrosion of the mucous membranes, oesophagus, and stomach, with nausea, vomiting, and diarrhoea reported in humans.  [Skin] contact may produce severe burns, ulceration, and scarring…. Acute animal tests in rats, mice, and rabbits, have demonstrated hydrochloric acid to have moderate to high acute toxicity from inhalation and moderate acute toxicity from oral exposure.

 

Chronic Effects: 

(Non cancer): Chronic occupational exposure to hydrochloric acid has been reported to cause gastritis, chronic bronchitis, dermatitis, and photosensitization in workers.  Prolonged exposure to low concentrations may also cause dental discoloration and erosion.  Chronic inhalation exposure caused hyperplasia of the nasal mucosa, larynx, and trachea and lesions in the nasal cavity in rats.  The Reference Concentration (RfC) for hydrochloric acid is 0.02 milligrams per cubic meter (mg/m 3) … The RfC is an estimate … of a continuous inhalation exposure to the human population (including sensitive subgroups) that is likely to be without appreciable risk of deleterious noncancer effects during a lifetime.  It is not a direct estimator of risk but rather a reference point to gauge the potential effects.  At exposures increasingly greater than the RfC, the potential for adverse health effects increases.  Lifetime exposure above the RfC does not imply that an adverse health effect would necessarily occur.
https://www.epa.gov/sites/production/files/2016-09/documents/hydrochloric-acid.pdf
 

 
Phosphoric Acid Risks

Phosphoric acid can be very hazardous in the case of skin contact, eye contact, and ingestion. It can also cause irritation if vapours are inhaled. This chemical can cause damage to the skin, eyes, mouth, and respiratory tract. Because of the potential hazards posed by this chemical, it is important to use care when handling it.
 
Repeated or prolonged exposure to phosphoric acid mist can lead to chronic eye irritation, severe skin irritation, or prolonged respiratory tract issues.  In case of accidental exposure to phosphoric acid, follow these first aid guidelines:

Inhalation — Seek fresh air and immediate medical attention.

Eye Contact — Remove contact lenses if present. Immediately flush eyes with plenty of water for at least 15 minutes and get medical attention.

Skin Contact — Wash skin with soap and water. Cover any irritated skin with an emollient. Seek medical attention. 

Ingestion — Do NOT induce vomiting. Never give anything by mouth to an unconscious person. Seek medical attention if any adverse health symptoms occur.
https://www.msdsonline.com/2015/06/17/phosphoric-acid-safety-tips/
 
  

Citric Acid

Citric acid can be a minor skin irritant, causing itchy skin and even minor burns to those that are sensitive to it. Hands should be washed immediately if citric acid comes into contact with bare skin. Protective gloves should be worn during handling to avoid any accidental contact. The acid can also irritate the walls of the throat if ingested or burn the lining of your stomach if ingested in large quantities.
 
Eye Irritation - Citric acid is a severe eye irritant. Accidental contact with the eyes can occur … by touching the eyes after the acid has contacted the fingertips. …  Protective eyewear should be worn when working with citric acid under laboratory conditions. Eyes should be flushed with water immediately if they happen to come in contact with the acid.
https://sciencing.com/hazards-citric-acid-8165149.html

Remember that this irritation is equivalent to squirting lemon juice into your eye.  It is not a chronic risk.
 

Hydrobromic Acid (HBr)

Hydrobromic acid and hydrogen bromide gas are highly corrosive substances that can cause severe burns upon contact with all body tissues. The aqueous acid and gas are strong eye irritants and [tear producers]. Contact of concentrated hydrobromic acid or concentrated HBr vapor with the eyes may cause severe injury, resulting in permanent impairment of vision and possible blindness. Skin contact with the acid or HBr gas can produce severe burns. Ingestion can lead to severe burns of the mouth, throat, and gastrointestinal system and can be fatal. Inhalation of HBr gas can cause extreme irritation and injury to the upper respiratory tract and lungs, and exposure to high concentrations may cause death. … Hydrogen bromide has not been found to be carcinogenic or to show reproductive or developmental toxicity in humans.
https://web.stanford.edu/dept/EHS/cgi-bin/lcst/lcss/lcss47.html#:~:text=The%20aqueous%20acid%20and%20gas,gas%20can%20produce%20severe%20burns.
 
 
 

Precautions to be taken by glass workers

The risks outlined above are related to dealing with concentrated amounts of the materials in industrial settings.  Risk levels are much reduced in the craft setting.  The risks are mainly centred on breathing and eye exposure. 
 
It is important to wear masks of the quality that will deal with inorganic fumes.  In Europe these are designated as FFP2.  In general masks rated at N95, P95, or R95 are the level required for filtering out 95% of particles that are larger than 3microns.  Dust masks are not sufficient protection. 
 

Usually overlooked is eye protection.  The risks outlined here show that risks to eyes are equal to - or in some cases greater than – respiratory ones.  Eye protection is as important as breathing filters.  To fully protect the eyes, goggles of some sort are the minimum requirement.  Glasses will not be sufficient to prevent fumes reaching eyes.

 
For a “one stop solution” a full-face mask may be the simplest solution.  The filters on these are long lasting and replaceable.  They can be put on as one unit and are available in various face sizes.
 

At soldering temperatures, there are no lead or tin fumes created.  It is the fumes from the flux that are the risks in soldering.  These risks are small and can be dealt with by using adequate ventilation, masks, and goggles.

Solder Touch-ups

 

Can you go back and solder again after cleaning if you realize a part needs touched up or to add jump rings?

Yes, it is possible.

There are some conditions, of course.

• Clean the area back to the bare solder.
• Use a small amount of paste flux to avoid lots of clean up of flux. Paste flux will stay pretty much where it is put and does not spread so much as liquid flux does.
• Apply the solder as usual for the area.
• Clean again as for the original soldering, but without metals.
• Rinse in cold water and pat dry.
• Add the patina immediately.
• Polish as usual.

Finished!

More complete discussion and information is here.

When to Apply Patina?

 Is patina able to be applied days later or does it need to be applied immediately?

The best method is to clean the solder with non-metallic mild abrasives. If the bare solder is left for a while, the solder needs to be cleaned again, as oxidisation begins immediately. Any oxidisation inhibits the patina reaction and provides an uneven finish.

Once the solder has been cleaned with non-metallic scrubbing, wash in cold water, dry at once, and immediately apply the patina.

Can you leave the solder silver with polish/wax until you decide which color and go back later? 

It may be possible, but it is not a complete protection against oxidisation. It will, of course, reduce the amount of oxidisation and make the clean up a little easier. But, any polish needs to be thoroughly cleaned off and the solder scrubbed clean, washed, and dried before applying patina. So it may be most simple to cover the soldered panel with plastic cling film (Saran wrap?), or in a sealed plastic bag until it is time to clean the solder and patina.

In both cases the important elements are to

• clean back to bare solder,

• clean with water,

• dry immediately and

• apply the patina acid right away.

Health Risks from Lead/Tin Solder

"Lead solder – is an open window or an open door in my greenhouse studio required, and in either case do I need some sort of extractor device."

The fumes are not from the lead or solder, they are from the flux.  Eye protection is important.  Gentle ventilation is sufficient.  A small fan to create a current of air to the outside will do of there is no other ventilation.

“If you give items away/sell them. What safety advice do you give to people.”

Lead is only dangerous if consumed.  It is not absorbed through the skin, only by transfer from the skin to the mouth.   Once the piece is handled, wash hands before eating, drinking or touching eyes.

“Is lead free solder a better option for small sculptures, which are not jewellery.”

The risks of lead poisoning are greatly exaggerated. If the pieces are not worn, the risks are minimal. If the pieces are not handled, there should be no transfer to the digestive system. Lead free solder is more difficult to work than a lead/tin alloy.

“What gloves are good to prevent cuts. I’m presuming disposable gloves are best for soldering.”

Skin tight cut resistant gloves are best, but are uncomfortable for long use periods. They can be used for soldering too. Honestly, I don’t use gloves for anything, and my blood lead levels have been below the minimum for the 30 years I have been working with lead and solder.

These are my opinons, of course.

The best guidance on health and safety for stained glass workers, is Greg Rawls’ website.  His career was in industrial health and safety until retirement a couple of years ago. He gives sensible, scientifically researched advice, which is not alarmist.

Metal Rods for Strength

I want to stick a steel rod inside the channel of the H section of lead came. Super glue doesn't work long term, any ideas what glue to use?

Some people advocate wrapping the rod with copper foil and use that as a base to solder the foil to the lead came. This relies on the strength of the adhesive just as super glue does. It will fail in the long term.

There is a method suggested by Gene Mallard years ago that I have used successfully. It encases the rod within two overlapping “H” cames and does not rely on glues at all. It is illustrated here:

Finishing Copper foil Projects

What order do you clean/wax/patina?

A question with many answers.

Almost everyone agrees that cleaning all flux and oil residues are the first stage of finishing. Once the panel is rinsed and dry the stage is set for the finish. The solder is then cleaned of any oxidisation by using steel wool, brass wire brush or some other mild abrasive.

However the industry does not use any metal in the cleaning of any surface to be patinated. Never use abrasive or corrosive materials to clean solder lines holding glass.  The most aggressive cleaner used is that intended for fibreglass baths. Do not use metal or scouring pads when cleaning.

Again opinion differs on the order of processes:

Some wax the solder lines and polish before applying patina.

Some apply patina and wax afterwards.

Both claim success with their method.

Comments from industry indicate that the order is:

Clean

Patina

Protect

Fluxed Foil

 If you take a breaks from soldering do you need to clean it right away or is flux okay to sit? 

Fluxes are mild acids. If left a long time, they will corrode the copper foil – not enough to damage it, but enough that the solder will not take to the foil as it should.   A long time is measured in days rather than hours.

If the flux has been left overnight, it probably will be OK.  The test is whether the solder flows as it did before the interruption.  If it does not, then the flux needs to be cleaned off the foil, and the foil polished with steel wool before re-fluxing.

Liquid flux needs to be used before it dries to be active.  Any interruption which will be long enough to allow the flux to become dry will mean a clean up of the surface is necessary before leaving the piece for a day or more.

Soldering Interruptions

Do you have to finish soldering/cleaning all in one go? 

Interruptions in soldering are possible, but they should not be long. The flux is an acid and will affect the copper foil. The acid although mild, will began to cause enough corrosion to make further soldering difficult after a few days or a week. If the recommenced soldering is not working as previously, the flux needs to be cleaned off and the oxidisation layer removed from the foil. The easiest way is to use fine steel wool and carefully polish the foil with it. Then flux the area you think you can accomplish in the time you have.

If there is likely to be a significant time before soldering can begin again, clean off the flux and finish with a neutralising compound, or a solution of baking soda. Dry and cover with a plastic sheet, or if small enough, put it into a sealable plastic bag.

If it is a big job in relation to the time available, only flux what can be achieved in that time. This saves clean up time. Although it may be necessary to polish a thin layer of corrosion from the foil before resuming the soldering.

Cleaning Solder Beads

After soldering, cleaning and drying your piece is essential to good patina results.  Ensure the panel is completely dry, not just the solder lines.  Many people recommend metal wools or brushes, but the information from industry is to use mild non-metallic materials to prepare the solder lines for patination.

Green scrubbies, or more environmentally friendly plastic free scrubbers are a good choice.  A short bristled plastic free brush that is not really stiff will work well too.  

The cleaning solution should not be anything more abrasive than that used on fibreglass bath fittings.  If this needs to be used to be sure of clean solder, the panel must be rinsed again with water that has as few chemicals and minerals as possible.

Omitting this step increases the chances of developing whitish blotches later on the solder lines. However, including this step makes a better base for applying the patina, if you are using any. 

Revised January 2026

Hinges in Sun catchers

How critical is it to reinforce hinge joints?

It is often suggested that straight, or nearly straight, joint lines need to be reinforced. “Restrip” or similar reinforcements within the hinge are often suggested to strengthen the panel.

However, such reinforcement within the bands will do nothing to resolve the hinge problem. To make a panel resistant to folding at the hinge, the reinforcement needs to be at right angles to the hinge. This will resist the bending of the panel most effectively.

If the hinge joint does not extend to the outside of the panel, external reinforcement will be needed from side-to-side to strengthen the panel against bending.

In a hanging item bending at a hinge is not the same kind of problem. What is a concern is that the pieces will separate. Edge reinforcement such as wire soldered to the edge all around the panel. This is because the adhesive is degraded by the heat of soldering and cannot be relied upon to hold the weight below the hinge joints.

Zinc came borders are often recommended as the solution to creating stiffer panels. It certainly has strength advantages, but is generally limited to straight lines or regular curves. For more free form pieces, soldering a thin copper wire to the edges and covering with hobby came provides a strong edge to a hanging panel. The wire also can provide strong hanging points independent of solder lines emanating from the interior.

Vase Cap Attachment

Tinning the brass

Brass transmits heat much more quickly than lead, so a considerable length or the whole of the piece, e.g., a vase cap needs to be heated to avoid the cap acting as a heat sink and so not allowing even tinning of the object.

When tinning any brass pieces, like a lamp cap, rub it with fine grade steel wool until bright, then wash the residue off and dry. Apply flux with a fresh flux brush, and hold the piece with a pair of pliers as a precaution against getting burnt.

At this point you can heat the brass or vase cap with a blow torch at a low heat to warm the whole piece. Begin applying the solder while playing the torch over the vase cap to allow the solder to flash along the brass smoothly.

Alternatively you can work without the blow torch. Apply a bit of solder to the tip of the iron. Touch the piece with your hot soldering iron, let the piece heat up a little, and then start moving the iron slowly and smoothly over where you have applied the flux. This does not provide as smooth a tinning as the blow torch method.

When the whole piece has been covered, wash it, dry, and then inspect for any missed spots or unsightly solder blobs. Apply a little bit more flux and touch with your soldering iron. If you are doing a lot of this kind of work, an 800 degree iron tip will speed up your work.

This method will give a strong solder to solder joint that requires much less time when soldering the cap to the rest of the lamp shade.

Attaching the vase cap

Tinning the vase cap is important to a secure attachment. The whole of the lampshade hangs from the attachment of the vase cap to the solder seams of the shade.

Once the glass of the shade is at least tack soldered, place the vase cap on top centrally covering the void at the top of the shade. Flux and apply solder so the solder seams to make sure the cap is securely fixed to the rest of the shade.

It is a good practice to turn the lampshade over and apply solder from the seam to the inside of the vase cap. For larger, heavier shades, it is important to run copper wires from the underside of the vase cap, near its centre into the solder lines for 5cm/2”. This often means that the wire will need to be bent in several directions to follow the seams, so a thin guage wire is most useful. This also implies multiple wires need to be run from the cap into the seams. I find multiples of three are important to maintain long term stability. So, 3, 6, or 9 wires may be needed. My usual is at least 6.

Choosing copper foil backing

Why are there different colour backings on copper foil?

This is a common question.   The answer has to do with the finished piece, and only matters if you are using transparent glass. If you are using opaque glass that you cannot see through it doesn’t matter so much which type you use.

The backing should be of the same colour as finish to the solder lines. Since you can see through transparent glass, you will be able to see bits of the back of the copper foil, especially at certain angles. It would look peculiar to have a piece with a beautiful black patina, only to catch glimpses of copper when you are looking at it.

Therefore, if you are planning to patina your piece black, use black-backed copper foil. If you are planning on leaving it silver, use silver-backed copper foil. If you are planning to patina it copper, use copper backed copper foil.

You can, of course, be safe and use black backed foil all the time.  Even if the final colour of the solder is other than black, the black will not attract the viewer's eye so much as a contrasting colour.

Choosing Copper Foil

 What foil should I choose?

Choice of foil relates to:

Glass thickness

Thin glass requires thinner foil to maintain a neat solder line of about 3mm. Thicker glass requires thicker foil to maintain the same width of solder line. So 2mm glass might require 4mm foil, and 3mm glass need 5mm foil.

Glass texture

Heavily textured glass usually needs thicker foil, as the thickest part of the glass is greater than the thickness of average glass. This requires a little experimentation to get the one you like best, but usually is one step up in width from your usual. Remember you are looking at only one half of the resulting solder line thickness on each piece of glass.

Desired width of solder line

The desired width of the solder line will also affect the choice of foil. If you like a thin line of solder, you should choose foil that is only 1 or 2mm wider than the thickness of the glass. This will give a solder line of 1 or 2mm wide. Be careful when choosing a thinner width. You still need enough foil on your glass to maintain the strength of the solder bead. If you like wider lines, a foil that is 3 or 4mm wider than the glass thickness will give a 3 to 4mm wide solder line.

Ease of Use

Foil comes in different thicknesses as well as widths. Thinner is easier to form around inside curves, but tears more easily. Thicker is more robust, but crinkles up more on curves and so needs more burnishing. Mostly it is personal choice on what is easiest to work with.

Trimming
Of course is possible to trim the copper foil to be thinner after foiling.  This can be to even up the line, or to thin it.  Gentle pressure with a sharp craft knife will cut the foil to the width you want. You may want to do this when all the pieces are assembled before soldering.  This gives you the opportunity to see the width of the resulting solder line will be.  It is also the time when you can see what the line of the solder bead will be and make adjustments before beginning the the soldering.

Care in the Operation of Soldering Irons

The most important element in the deterioration of soldering iron bits is long idle times. This is where you leave the iron on, and not in use, for a long time.

Have everything ready when you start soldering, so the iron will be used continuously, and will not sit there building up heat, while you get ready to use it again. An idle iron will keep heating to its maximum capacity, and without anything to transfer the heat to, it will start burning off the tinning, after a short while. So if you will not be using the iron for a while turn it off until you are ready again.

Even if you have a temperature controlled iron, idling for a long time at the set temperature does have the same but lesser effect as one without temperature control.  

The other elements leading to deterioration in performance come from lack of cleaning and tinning of the tip. When the coating of solder burns off or is coated with carbon you get poor heat transfer from tip to working surface making it appear that the iron is not heating properly.

An example of a heavy stand

It is important to ensure your electrical supply cord is kept away from the hot end of the iron to avoid burning through the cord.  In another studio the supply was from overhead so the cord was never trailing across the work or the bench.  A solid stand to place the iron into is important to both avoiding damaging the electrical supply and melting other things around.  To assist this, all materials not relevant to the soldering process should be put away before the soldering begins.

Protect yourself from burns from the iron or hot solder.  Always keep your hands away from the hot end of the iron.  Always place the iron into the holder when making adjustments of any kind that interrupts the soldering.  Keep burn relief, such as aloe vera by the soldering station.

Eye protection is important, because the flux fumes often contain chlorine compounds that can affect your eyes.  This is more important than breathing protection.  If good ventilation is being used, that will be enough for lung protection, and will reduce the risk to eyes, even then, eye protection should still be used.

Templates of Openings

 If you have an irregular opening to fill, it is best to take a tracing of the opening. Usually this will be in larger openings and a helper may be necessary to assist.

Materials

The material used to take the template must have a few characteristics:

• It must be stiff enough to have the minimum possible bend over the width or height of the opening

• It must be easy to mark with a pencil or other implement

• It must be easy to cut or shape

• It should be light to make it easy to lift it to the opening for the many adjustments that will be required.

A number of materials can be used: stiff card, mounting board, corrugated cardboard, thin plywood, and many other sheet materials. I have found double walled stiff corrugated cardboard easy to use.

Irregular rectangles

If you have found or can see that the opening is not a true rectangle and cannot determine where any right angles are, you need to take a template.

The objective is to make a piece that will fit into the opening without bending or being too small for the space. It will be the same size as the finished panel and so you will be able to put the finished panel into the opening without needing to trim or expand the panel.

First, trim the sheet of material you have chosen to use to a size a little larger than the measured size. Place the uncut side along one of the long sides of the opening. If the opening is a portrait format, place it on the right or left side as convenient to you.

Next, adjust the bottom by marking a line on the sheet. This is where a second person is very useful. One person can hold the sheet in place on outside of the opening and the other do the marking from the inside –in the case of the rebate being on the outside and vice versa if the rebate is on the inside. The marked line should be as close to the edge of the rebate as possible. The special case of an opening in stone will be dealt with separately.

Then take the sheet to a place where it can be safely cut. A long metal straight edge and craft or “Stanley” knife are often the best aids to cutting straight lines. Replace the sheet into the opening after cutting, and make any adjustments to the size and angles of the sheet at the bottom by marking and cutting as necessary.

When the side and bottom are adjusted, start on the other side. Proceed as for the bottom. When the side is finished, start on the top. Finally, present the whole sheet to the opening to make sure it slips into place with no snags, or bending of the sheet.

It may be that the opening is too large for a single sheet. In that case you will need to work with two or more sheets and try them together for the final fitting into the opening. You can put them together in the window. You can fasten them together with tape or other fasteners to make one sheet. You can also make two parallel lines both at angles and at intervals across the sheet so that when you get back to the studio you can exactly reproduce the full sheet by matching the marks and then firmly fastening them together. This makes transport of large templates much easier.

You will know that a panel made to a template made in this way will fit into the opening, no matter how irregular the opening may be.

Circles

Occasionally the window is circular and sometimes an oval. In both cases a template is important. The circles and ovals are rarely is exact or symmetrical. Take the template in the normal way and then ensure you mark the verticals and horizontals for the opening. You often can use the jointing in the woodwork to help with these. Also mark any other reference points from the opening. Finally, mark which is the outside and which the inside.

Round heads

Round headed openings can be considered as a special case of a circle. The horizontal you must find is the shoulder of the window. This is the place from which the curve springs on each side. The opening is generally vertical up to this point and then begins the curve.

You need to make sure you have marked where this shoulder is on the template. You should indicate any reference points from the frame onto the template.

The join to the lower part of the window must be made obvious. Normally there will be an overlap between the lower rectangular template and this approximate half circle. You need to mark where this overlap occurs, if you do not fasten the two sheets together. This can be done by marking across the two sheets in a few places. This will enable you to join them exactly back at the studio.

Irregular openings

Irregular openings such as trefoils and other tracery need to have templates taken with consideration on how the final panel can be put into the opening. In the cases where the whole of the rebate is exposed, it is normally possible to put the panel in as a single whole piece.

So, the template is taken as for any other opening. It is more complex and time consuming as there are so many more sides than in a simple rectangular or circular opening.

Stone

When the opening is in stone, slight variations occur in the process of taking a template. The main difference is that the rebates are concealed. The rebates are slots into the stone. Thus, the template must slip into the slotted rebate. In these cases, the stiffer the material being used to take template, the better. Usually, thin plywood is the best material, as it has to be manipulated many times and in ways similar to the final panel.

Things are further complicated, as tracery is more common in stone than in timber framed openings. A complex opening shape may require two or more parts to enable the panel to be inserted. The taking of a template will help greatly in figuring out how the panel will be inserted into the opening.

Additionally, when the template is in position, you should mark the visible portion of the opening onto the template. Mark which is the inside and which the outside. Finally, mark on each template which side has the deeper slot as this will help in installation.

Using these methods of taking templates will make restoration or drawing up a new design much easier and more accurate, leading to an easier installation.

Air Brushing on Glass

Air brushing paint and enamels onto glass can give extremely subtle graduations of colour and tone.

Air brushing onto glass is a little different than onto other slightly absorbent surfaces. As glass cannot absorb the moisture from the material being sprayed, the medium needs to be allowed evaporate.  This means that each layer of paint must be allowed to dry before the next layer is applied.  If too much liquid is applied to the glass, it will bead up giving a stippled appearance to the finished result.

The two main media that you can use are water and alcohol.  The advantage of spirits is that it evaporates from the surface more quickly than water.  Also apply in a warm rather than cold place. You can use a hair dryer on low speed and power to assist the drying.  This will reduce the waiting time between applications.  You do not need to use any gum arabic in the mix to help it flow, but a drop of liquid soap will help to break the surface tension of the medium.  This avoids any "beading up" on the super clean glass.  

The consistency of the mix of the paint or enamel with the medium will need to be many times thinner than that used for painting with a brush. Also the air brush will need to be able to cope with the relatively large (in relation to inks and other paint) particles that make up the glass paint. This may require a little experimentation to find nozzle sizes that can cope with the glass paint particles.

Before you begin air brushing you must prepare the glass so it is very clean.  Clean the glass very well with clean water followed by isopropyl alcohol.  After this thorough cleaning and drying, use some of the paint to rub the glass. As the paint is a slight abrasive, it cleans off anything the other cleaning methods could not get off.

The paint should be applied in steady sweeps across the area to be covered at least 10cm/4" from the surface.  Start moving your brush before you switch on the paint and keep moving after you stop applying the paint.  This avoids heavy applications at the start and finish. As there is no absorption of the moisture by the glass (as there would be on paper or board), you must pause after a very few passes.  This is where the spirits show their value, as they evaporate more quickly than water, allowing you to apply the next layer sooner.

One thing you will notice is that the paint will settle within the medium unless you agitate it frequently. So you should make sure the paint is evenly dispersed within the container by agitating it before starting each layer. The movement of the air brush during application will be enough to keep the paint suspended in the medium while you are applying the glass paint or enamels.

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Because air brushing puts very small particles into the air you need to observe various precautions. You need to have a dust mask on at all times you are air brushing. You should do this in a spray booth with extraction if possible. If not, you need a well-ventilated area and very good clean up afterwards.