Soldering problems and tips, chart

PROBLEM	PROBABLE CAUSE
Solder falls through seams to other side when soldering copper foiled pieces.	Soldering iron is too hot or you are holding the iron in one area too long. Put a damp rag or sponge under the area you are soldering.
Beading of seams is too flat.	Not enough solder.
Beading is lumpy -- peaks instead of flowing.	Iron is too cold.
Can't seam to get beading smooth.	Wrong kind of solder for job. Did you flux? Iron too cold or too hot. Too much or not enough solder.
Solder won't stick to copper foil or lead.	Did you flux? Copper foil may be oxidized; clean with vinegar, salt, and water solution. Lead may be oxidized; wipe clean, dry, and rub with fine steel wool or wire brush.
Solder splatters into little balls all over the glass.	Iron too hot; purchase rheostat for your iron. This will control the current to your iron and control the heat output.
Lead came melts and disappears before your eyes.	Directly touching the lead came with a very hot iron. Position solder at joint, iron on top. Let solder flow down on lead came.

Soldering tips from a pro

When we teach beginning stained glass classes we notice that quite a few of our students have issues and questions with soldering.  It is only natural!  It can be quite a daunting task for a student who has never soldered before.  I have come to the conclusion that there are two groups of new stained glass solderers, ones that get it right away and others that need to practice, practice, practice.  So today I thought I'd try to explain to new stained glass artists how to solder properly!

To begin with, you will need the correct foil, solder, flux and soldering iron.  In fact, you will also need a good work surface as well.  We solder our windows on top of a sheet of particle board which we lay on top of our work bench.  We prefer not to solder directly on top of our bench since flux will flow into and onto the work surface you will use.  Not to mention that you can scorch the surface you are soldering on.  We want to keep our work surface clean for making patterns, cutting our glass etc etc, for that reason we keep our table top flux free!

As far as using the correct foil, what we mean by that is,  using clean foil. That means foil that doesn't have the backing glue on the outer copper surface or contaminated with other materials.  If the foil is contaminated carefully clean it with either rubbing alcohol or Goof-Off.  When foiling you need to foil the pieces with equal foil on the front and back side of the piece of glass.  The foil needs to be flattened down with a fid (a flat plastic stick or even a pencil) to make a nice smooth surface for soldering.  If the foiling is flawed or sloppy, the solder job will also look flawed since you can't add additional solder to an area that doesn't already have foil.  So take your time when foiling and do a good job, or it will show later.  When soldering lead came, the came needs to be clean too.

For solder we prefer to use 50/50 solder for lead came and 60/40 for copper foil.

With flux we like to use paste flux for lead came and liquid flux on copper foil.  There are types of flux that seem to sputter when heated.  We try to stay away from those brands of flux.  They can actually become dangerous by allowing small particles of molten solder to become air born and perhaps land on skin or clothing.

We advise glass artists to use soldering irons made for stained glass.  Some irons used for circuit boards do not heat up enough to work properly.  Other irons only have small iron tips which can make it very difficult to solder easily.

Once all of the above conditions are met, it is time to start soldering.  We start soldering on the front side of the window, once completed we flip the window over, solder the back side completely, then flip the window over to repair the front where solder may have flowed from the back to the front.  We flip the window back and forth until we are happy with the soldering.  If the window is to have a zinc frame, we solder it on at this time, as well.

On the front side of the window, when we begin to solder a piece, we like to tack solder all of our glass pieces into place.  By that I mean, we like to put a little solder on every piece just to keep all pieces from moving and distorting the window's shape, as we solder.  We do butt our window up to the outer area of our work surface where we nailed two strips of wood trim into a 90 degree angle (we do this to keep our window square).  As seen in the picture below.

Photo from the Colson Stained Glass Studio

First apply the flux to the entire piece.  We use a small paint brush which can be purchased at most stained glass retailers.  When soldering you want the solder line to look rounded, not flat.  If an area looks flat, add more solder so that the solder line is rounded!  It is not necessary to solder in any specific manner, it is more important to have the correct finished look.  If you end up with rough, dull colored soldered areas, that is indicative of cold solder.  To repair an area like that, add a little more flux to the area and heat up the area with your soldering iron.  You also don't want excessive blemishes and large clumps of solder.  To repair, re-flux and re-solder.  It is not necessary to always add more solder, it is possible to just heat the offending area with your iron and correct the issue.  

When done soldering, both sides, wash off the flux.  Flux can eventually deteriorate the solder if left on the window.  We clean the flux off our windows by using a sponge with a small amount of dish detergent.  

Finally, please watch the soldering video we previously posted SOLDERING COPPER FOIL.  There are other soldering videos on You Tube and online which are excellent to watch and give hints and tips to new glass artists.

Soldering irons for glass art

Again, we always recommend that our students purchase a soldering iron specifically made for stained glass.  There are irons made for soldering pc boards that really won't work well for soldering foil or lead came.

Also when soldering lead came our studio glass artisans at Harrach Stained Glass always use  temperature controlled irons or we plug our irons into a Mini Phaser which is pictured below.  Just plug an iron into the Mini Phaser and control the iron's temperature by using the dial on the front of the unit.

We have found that a lot of glass artists prefer to use 60/40 solder for all of their soldering needs.  At our studio we use 60/40 solder on copper foil and 50/50 on lead came.  We also prefer paste flux for lead came and liquid flux for copper foil.

It is also important to always use an iron stand, to allow the iron to be easily laid down while still hot or plugged in, without burning a work surface!

There are quite a few different wattage irons available, such as 40w, 50w, 60w, 80w, 100w and 175 watts.  Some irons have ceramic heating elements, which are supposed to last longer than non ceramic elements.

Weller

Hakko

Inland

How to repair a broken piece in a leaded glass window.

Occasionally a glass artist will be asked if they can repair a broken leaded glass window but are not sure how to go about repairing the piece.  I think that repairing a leaded glass window is much easier than repairing a copper foiled window.  

To begin with you should tape together what is left of the broken piece of glass.  If necessary make a rubbing of the window.   Tape a piece of white paper on one side of the window,  lightly rub the window with a crayon or charcoal so that you can see the shadow of the lead came lines.

Next, remove the frame.  If you have a zinc came frame, you need to use a temperature controlled iron so that you can turn down the heat.  Then with the temp turned down, heat up and actually carefully move the solder from the soldered areas on the zinc came frame, use paste flux on the joint so that the solder will flow.  This will allow you to "break" or open up the soldered joints.  You'll have to do this on the corners of the zinc frame and the areas where the lead came is soldered to the zinc frame as well, remember to do both sides of your window.  Carefully remove the zinc frame from the closest side to the broken piece of glass, you might have to remove two sides of zinc came.  

Once removed, use your lead knife and cut into the closest soldered joints so that you will be able to open up the window to remove the broken piece of glass.  You will have to cut both sides of the window, in the same spots.  You might only have to cut up one area, but if the piece is large and you can't get into the broken piece, you will probably have to cut up into the window in two areas.

When you have cut both sides of lead came (only on the solder joints), front and back, up to the broken piece of glass, carefully remove or open up the window to where the broken piece is located.  Once there carefully remove the broken piece of glass with needle nose pliers.  Since the piece is cemented in place, it might take some work to pull the piece out.  Use your lead knife to clean out the lead came surrounding the once broken piece of glass.  If the lead came is damaged, you will then need to replace it.

Use the old piece of glass as a template to make a new paper pattern to replace the glass.  Place the broken piece of glass on a piece of paper, trace around it with a pencil, and cut it out with regular scissors.  Glue that piece of paper to the new replacement glass, cut, grind and its ready to replace.

If the piece of glass is too broken, or non existent,  to use as a template to make the new piece of glass, use the rubbing you made of the original window to make the new paper pattern piece.  We like to make a copy of that template first before doing anything else, just in case.  Take one copy of the etching and with regular scissors, cut out the piece or pieces that needs to be replaced.  When cutting, cut close to the center of the lead line that was traced in the original rubbing.

Once new pieces are cut and installed, re solder the once cut lead came joints.  By doing it this way, it is impossible to tell that the window has been repaired!  Then if the piece has a zinc frame, solder it back on before cementing.

Cement, clean and polish the window and it is now repaired!