Mending Cylinder Glass with Lead
Post new topic   Reply to topic
Historic HomeWorks Forum Forum Index -> Windows & Doors Goto page 1, 2  Next 
View previous topic :: View next topic  
Author Message
SashGuy



Joined: 10 Sep 2010
Posts: 152
Location: Houston

PostPosted: Mon Dec 05, 2011 11:01 pm    Post subject: Mending Cylinder Glass with Lead Reply with quote

I ran across a 1907 last month that had a cylinder glass single light that had cracked and was mended with lead. By the oxidation of the lead, it appeared to have been done quite some time ago.
Was this a common procedure around the turn of the century?
Has anybody performed the process?
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2968
Location: Portland, Maine, USA

PostPosted: Wed Dec 07, 2011 8:06 am    Post subject: Reply with quote

I have not seen or heard of it before, but it seems like a good idea: repair what you've got, rather than replacing it. Did they use ordinary lead came, like is used in stained glass work?

Here is another unusual repair method. On my own barn, here in Portland, Maine, built in 1899, there is a broken pane in the double hung window that was repair with the greenhouse method of glazing. Within one light, there are two pieces of glass, overlapping about 1", with special angled glazing points that look like bent staples. For several years I could not understand why that method was used, and then through deed and tax research I learned that in 1924 there was a 100' long greenhouse attached to the barn. So, obviously, the guys building the greenhouse repaired the broken window.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Vic



Joined: 05 Mar 2006
Posts: 59
Location: NYC

PostPosted: Sat Dec 10, 2011 7:12 pm    Post subject: Re: Mending Cylinder Glass with Lead Reply with quote

SashGuy wrote:
I ran across a 1907 last month that had a cylinder glass single light that had cracked and was mended with lead. By the oxidation of the lead, it appeared to have been done quite some time ago.
Was this a common procedure around the turn of the century?
Has anybody performed the process?


The potental problem is
1- The center of the lead came , called the heart, is about 1/32"-1/16"
thick. So the glass may need to cut down a bit.
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2968
Location: Portland, Maine, USA

PostPosted: Sun Dec 11, 2011 9:46 pm    Post subject: Reply with quote

Vic:

OK, I'm going to give this a try on a single crack across a pane of glass. This crack is on a diagonal, and the glass was cut a little undersized, so there's plenty of room for the heart of a lead came.

Sure, the lead came will show, but it's on a barn and it seems like a good sustainable repair method to reuse the original glass.

Can you briefly suggest a step-by-step method with materials suggestions?

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
SashGuy



Joined: 10 Sep 2010
Posts: 152
Location: Houston

PostPosted: Mon Dec 12, 2011 12:23 pm    Post subject: Reply with quote

johnleeke wrote:
Vic:

OK, I'm going to give this a try on a single crack across a pane of glass. This crack is on a diagonal, and the glass was cut a little undersized, so there's plenty of room for the heart of a lead came.

Sure, the lead came will show, but it's on a barn and it seems like a good sustainable repair method to reuse the original glass.

Can you briefly suggest a step-by-step method with materials suggestions?


Hang on John, Don't expend your subject. I'm taking some photos and will post how this old master did it.

I have two 32 x 30's to do myself for a customer, so, if successful, I'll post the procedure.
Back to top
View user's profile Send private message
SashGuy



Joined: 10 Sep 2010
Posts: 152
Location: Houston

PostPosted: Mon Dec 12, 2011 3:14 pm    Post subject: Reply with quote

I just returned from the home with pictures.

These are posted at http://sashguy.com/lead.htm

There is no came.

I went after this with a magnifying glass, and it was done with flux and solder only.

The patina of the bead appears to be very old, and the bond is such that it does not flex or leak.

Under the seam, and up against the glass, there appears to be some flux residue.

I would guess that they relied on the lead content of the glass and the flux to form the bond.

In my estimation, and the process that I will try, is to;

Remove the sash

Remove the glazing at the break

Clean and buff the glass both sides

Lay a strand of 60/40 flux core solder (for low melting temp)

Run a flat tipped iron slowly down the strand to allow full melt and penetration of the break
(Being careful not to touch the glass with the iron)

Flip it over and perform the process on the other side

Buff it out to smooth the lead surface and remove the flux


I will be doing this later in the week, but if anyone has time to make a run at it, please report back with your findings.
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2968
Location: Portland, Maine, USA

PostPosted: Mon Dec 12, 2011 3:28 pm    Post subject: Reply with quote

Is it possible there is copper, brass or bronze foil under the lead?

How much does the lead rise above the glass surface?

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
SashGuy



Joined: 10 Sep 2010
Posts: 152
Location: Houston

PostPosted: Mon Dec 12, 2011 3:54 pm    Post subject: Reply with quote

johnleeke wrote:
Is it possible there is copper, brass or bronze foil under the lead?

How much does the lead rise above the glass surface?


If there is, I could not detect it. If appears that they did this directly onto t he glass and let the molten solder penetrate the crack. The max rise was less than 1/16"and the bead was very uniform at 1/4"

How they got the solder to remain liquid until it had penetrated the crack will have to remain a mystery until we have mastered it.

I did not detect any heat discoloration such as would have been left by a torch, and would imagine that a flame would have shattered the glass, hence my choice of a flat tipped iron. What puzzles me, is the crest is very smooth to have been formed by an iron.
Back to top
View user's profile Send private message
cabinfeverarts



Joined: 05 Aug 2008
Posts: 114

PostPosted: Tue Dec 13, 2011 11:10 am    Post subject: Reply with quote

Solder will NOT adhere to glass. The best you will get is a blob-y mess. If this is not lead came, then it is a copper foil repair. There is a copper foil tape wrapped around each edge of the two pieces. The copper foil method is not considered waterproof. You can never get the tape smooth enough to completely eliminate water or air penetration. That is the putty's function with lead came. Putty & came is also better for exterior windows because it provides a cushion for the glass. A copper foil repair is more rigid and when there is movement such as wind, the seam doesn't give, so the glass cracks.

So my opinion is if this is the copper foil method, you lucked out in this particular case that the joint hasn't caused further damage or had noticeable leakage. In general, this is not the case. So it's not a good idea to duplicate this type of repair. A came/putty repair would work just fine, but as Vic said there would have to be space to fit the heart of the lead.

But looking at the pictures, it's pretty hard to tell if it's not a lead came repair. The edge of the "solder" or "lead" looks sharp and less rounded. A sharp, boxy edge is probably lead came. I looks like it might even have a little putty pushed under that edge.

_________________
Sidney
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Vic



Joined: 05 Mar 2006
Posts: 59
Location: NYC

PostPosted: Tue Dec 13, 2011 2:12 pm    Post subject: Reply with quote

SashGuy wrote:
I just returned from the home with pictures.

These are posted at http://sashguy.com/lead.htm

There is no came.

I went after this with a magnifying glass, and it was done with flux and solder only.

The patina of the bead appears to be very old, and the bond is such that it does not flex or leak.

Under the seam, and up against the glass, there appears to be some flux residue.

I would guess that they relied on the lead content of the glass and the flux to form the bond.

In my estimation, and the process that I will try, is to;

Remove the sash

Remove the glazing at the break

Clean and buff the glass both sides

Lay a strand of 60/40 flux core solder (for low melting temp)

Run a flat tipped iron slowly down the strand to allow full melt and penetration of the break
(Being careful not to touch the glass with the iron)

Flip it over and perform the process on the other side

Buff it out to smooth the lead surface and remove the flux


I will be doing this later in the week, but if anyone has time to make a run at it, please report back with your findings.


As stated by Cabin, You can NOT solder directly to the glass. I am not aware of any window glass with a lead content. "Lead" glass is soft and used for decorative cut crystal of high quality optical glass. Your photos are not clear enough to see whats going on. One photos looks like there may be putty under the solder. Thus indicating lead came. The surface seems to have a texture. It is not uncommon for the surface of the lead came to be "tinned", that is, floated with solder.
Again as Cabin said this my even be foiled. Hard to tell

John
A copper foil repair, that is wrapping both glass edges with foil and soldering usually will not require much space between the broken glass. However if the glass is large and uneven in thickness, you run the risk of heat breakage when soldering. A lead came repair may not even have to solder at all. Just make sure that the ends of the came go into the sash rabbit. Be aware that the thickness of the came will NOT allow the glass to lay flat against the rabbit. So maybe a shallow grove should be cut into the rabbit to receive the came. Putty under the came. For a bit more strength and better weatherproofing. Take a putty knife and GENTLY fold down the outer edge of the came to the surface of the glass, after putty.
The wider the came face the stronger the came. I'd say 1/4"-1/2" wide came depending on your needs and aesthetics
Back to top
View user's profile Send private message
Vic



Joined: 05 Mar 2006
Posts: 59
Location: NYC

PostPosted: Tue Dec 13, 2011 2:17 pm    Post subject: Reply with quote

Quote:
How they got the solder to remain liquid until it had penetrated the crack will have to remain a mystery until we have mastered it.
.


Assuming that you can get the solder to penetrate the crack without do more damage (doubtful). The hot liquid solder would just flow out the other side, unless you find a way to stop it
GOOD LUCK!
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2968
Location: Portland, Maine, USA

PostPosted: Tue Dec 13, 2011 2:51 pm    Post subject: Reply with quote

Vic, do you see any disadvantages or have any tips on this:

Here is a procedure using the foil method that could work. Wrap foil around the cracked edges with pieces of thin (1/32" or 1/64") cardboard to hold the foil up off of the faces of the pane. Do the soldering. Make the solder thick enough that it holds itself and the foil up off the glass during the next steps. Remove the thin cardboard. Work putty into the space between the foil and the glass with a tooth brush. Clean up with the usual polishing with a dry paint brush and whiting.

Advantages:
- the edges of the cracked glass could be closer together that with using lead came since there are only two thin pieces of foil
- the cardboard would insulate the glass from the heat of soldering reducing the risk of breaking the glass
- the putty provides a water and air seal
- materials cost less than buying a new piece of glass
- keeps the original glass in place which is good preservation
- it's reversible, which is good conservation

Disadvantages:
- the repair shows, but it could be acceptable where appearance does not matter, or where conservation trumps appearance

I think I would do this while reglazing the sash, during the steps of bedding the pane in the putty and setting the glazing points. I would bed the larger piece of glass and set the glazing points in it. Then apply the foil and cardboard to that edge. Then apply the foil and cardboard to the edge of the smaller piece, then bed and set the points in that piece of the pane. Then do the soldering. Then remove the cardboard and work the putty into the joints while finishing up with running the line of putty around the whole pane in the usual way.

What are the method and materials used for sealing lead came to the glass in stained glass work?

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought


Last edited by johnleeke on Tue Dec 13, 2011 3:10 pm; edited 1 time in total
Back to top
View user's profile Send private message Send e-mail Visit poster's website
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2968
Location: Portland, Maine, USA

PostPosted: Tue Dec 13, 2011 3:01 pm    Post subject: Reply with quote

With the lead came method on a single crack, not soldering is a big advantage over lead-foil because it saves time and has less risk of heat-cracking the glass.

How the lead came meets the glazing rabbet will be easy to resolve because the lead is soft and can be easily formed and trimmed. I think thinning down the side of the came that lays in the bedding putty would be easy. The glass is usually a sixteenth off the shoulder of the glazing rabbet anyway.

Lead came would definitely be the slick and quick method.

I'll stop in at my local stained glass shop to see what they have on hand in the smaller sizes.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought


Last edited by johnleeke on Tue Dec 13, 2011 6:26 pm; edited 1 time in total
Back to top
View user's profile Send private message Send e-mail Visit poster's website
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2968
Location: Portland, Maine, USA

PostPosted: Tue Dec 13, 2011 3:06 pm    Post subject: Reply with quote

In comparing these methods with using adhesive, does anyone have projections or actual experience on how long the adhesive repairs last?
_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Vic



Joined: 05 Mar 2006
Posts: 59
Location: NYC

PostPosted: Tue Dec 13, 2011 6:53 pm    Post subject: Reply with quote

johnleeke wrote:
Vic, do you see any disadvantages or have any tips on this:

Here is a procedure using the foil method that could work. Wrap foil around the cracked edges with pieces of thin (1/32" or 1/64") cardboard to hold the foil up off of the faces of the pane. Do the soldering. Make the solder thick enough that it holds itself and the foil up off the glass during the next steps. Remove the thin cardboard. Work putty into the space between the foil and the glass with a tooth brush. Clean up with the usual polishing with a dry paint brush and whiting.

Advantages:
- the edges of the cracked glass could be closer together that with using lead came since there are only two thin pieces of foil
- the cardboard would insulate the glass from the heat of soldering reducing the risk of breaking the glass
- the putty provides a water and air seal
- materials cost less than buying a new piece of glass
- keeps the original glass in place which is good preservation
- it's reversible, which is good conservation

Disadvantages:
- the repair shows, but it could be acceptable where appearance does not matter, or where conservation trumps appearance

I think I would do this while reglazing the sash, during the steps of bedding the pane in the putty and setting the glazing points. I would bed the larger piece of glass and set the glazing points in it. Then apply the foil and cardboard to that edge. Then apply the foil and cardboard to the edge of the smaller piece, then bed and set the points in that piece of the pane. Then do the soldering. Then remove the cardboard and work the putty into the joints while finishing up with running the line of putty around the whole pane in the usual way.

What are the method and materials used for sealing lead came to the glass in stained glass work?

The foil is VERY thin. The strength comes from building up a solder bead. The copper foil is adhesive backed, so it will stick to the card board. The option would be to make your own foil. I don't see the advantage here. Too much work,IMO
Back to top
View user's profile Send private message
Display posts from previous:   
Historic HomeWorks Forum Forum Index -> Windows & Doors Goto page 1, 2  Next 
Post new topic   Reply to topic All times are GMT - 5 Hours
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum