Custom Glass Reproduction?

[B Jake Moran]

Not sure where I should have put this topic for maximum viewage.  

 

I am looking at a 1957 International Travellall.  An old vehicle probably no one on here is considering.  

 

I looked at it on Tuesday.  A Travelall is an International "Suburban".   The problem with a 1957 Travellall is that the glass on the rear sides are curved and specific.  NOT flat glass.  I owned a 1949 Chevrolet Suburban and the side glass could have been made from "scratch", so to speak.  

 

The rear most glass has a curve in it, specific to a 1957 to about 1960 Travellall.  Caveat here:  I am no International expert.  

 

I saw a 1957 Travellall at a local junkyard that sells projects.  It has no drivetrain, is a 4WD model, a 3/4 ton 1957 Travelall.  The body hails from North Dakota.  A sister 1957 4WD truck, complete, has already sold.  

 

The issue here why this interesting (to me) early SUV is still for sale is the lack of a drivetrain AND cracked rear long windows on both sides.   To me, these are likely non available, although I continue to look. 

 

I think others seeing this rare SUV have said no way, because that rear glass is unobtainium. 

 

I have to believe I am not the 1st to deal with this "glass" issue.   The 2 rear curved glass pieces in the vehicle I am considering are fully intact, and secured now within their gaskets.  They would make great templates, but is that a "thing" with glass?  

 

I am asking - can glass be made even if a "one off" from a core sample?  How is glass made?  

 

I can not believe International, an essentially basic "truck" manufacturer - would contract for rear curved glass in their Travellall, and I was even more dismayed to go look at this vehicle and see long complicated cracks in BOTH of the rear specialty glass pieces.  

 

I would hate to pass on this project because of "glass".  Yet there it sits.  

 

[Gary_Ash]

Curved glass is made by “slumping” the glass in a hot oven/furnace.  Usually a form is made from angle iron. For laminated glass, two sheets of flat glass are stacked and loaded onto the frame, put in the oven, and allowed to slump until the edges are in full contact with the angle iron frame. Then the glass and frame are pulled from the oven and allowed to cool slowly to avoid stress. Later, the two sheets of glass are laminated with PVB plastic for shatterproof glass. It’s likely that some company still has the tooling for the glass, though it may be tough to find them. There are some small companies that will do custom glass, but the tooling is probably expensive and you would need the exact dimensioNs of the opening where the glass goes. Tempered glass is a single thickness of glass but slumped in the same way, then rapidly cooled to stress the outer skin. If you can see cracks, it is most likely laminated safety glass. 

 

You might consider replacing the side glass with acrylic sheet slumped to shape, cheaper tooling and lower temperatures.

[Bhigdog]

I talked a few years ago to a guy that had a pair of custom curved side glass windows made. The first one was $5000. The second $ 250.....just sayin...maybe BS. Maybe not......bob

[EmTee]

I believe I saw a "Wheeler Dealer" episode a few years ago (when Mike & Edd were in CA) where they found a glass shop that cut custom curved glass panels from stock windshields that had the curves that matched the pattern they were trying to replicate.  I think in that episode they cut a new windshield for an old Saab from another, newer car's stock windshield (I forget what car it was made for).

[Shootey]

I assume someone makes the curved rear side glass for 1955-57 Chevy Nomads. I wonder if they could do the International. 

[B Jake Moran]

34 minutes ago, Shootey said:

I assume someone makes the curved rear side glass for 1955-57 Chevy Nomads. I wonder if they could do the International. 

Good point.  And they did not make a ton of Nomads.  

[Rusty_OToole]

If it was me I would first ask if auto glass shops could supply new glass. If that failed  try to find used glass from a junkyard International. If that failed, make new  windows of acrylic or plexiglass. You can form that stuff at home with heat, and it will last a long time if not knocked around. Won't do for a windshield because of wiper rubbing but should last for many years on the side windows.

[Laughing Coyote]

2 minutes ago, Rusty_OToole said:

make new  windows of acrylic or plexiglass.

When I was doing wrought iron back in the day I had a custom handrail job for a very expensive house which included glass panels. The bottom glass panels going up the grand staircase were curved.  The cost of getting curved glass was very expensive.  I had a local company do curved panels that were a plexiglass type material.  Matched the real glass in color.  Couldn't tell.  Cost was way cheaper.  Just an option until you can find the right stuff.

 

[Bhigdog]

Plexiglas, acrylic, or whatever is not glass, nor will it ever be, nor will it ever look close to glass. Do it right or not at all.............Bob

[Rusty_OToole]

7 minutes ago, Bhigdog said:

Plexiglas, acrylic, or whatever is not glass, nor will it ever be, nor will it ever look close to glass. Do it right or not at all.............Bob

And how exactly do we do that?

[Ozstatman]

Forum member TTR says he makes windscreens. Maybe he can provide some advise?

 

Speaking of curved glass, although it was to replace one the flat windscreen sides in my 41 Packard Coupe, guy at the glass shop said if it ever became necessary to replace the curved glass rear windscreen he could do it by cutting out a section from a Holden Commodore front windscreen. Apparently, to his experienced eye, it was about the same shape/curve.

[wayne sheldon]

About forty years ago, I had to have some glass work done. At the time, I was looking at a project that if I got it would need some special curved glass. I talked to a couple local shops that told me they did that all the time, how easy it was (yeah, IF you have the setup for doing it!), and how cheap it was. They also said I could get either ,aminated or tempered, as long as tempered wasn't used in the windshield (tempered might not shatter and can crush a skull or break one's neck!).

Apparently a few shops doing that work kept them competitive (who would have ever guessed?)! But those people eventually retired, and their shops closed down.

Two different local shops told me they were set up to do it, and if I got the project (I didn't), they could have the glass ready to pick up in a week.

 

Just another thing our no-can-do anymore world has lost.

 

The point being, that when these IH Travel-alls were in daily use, replacing the windows was not a problem.

[Bhigdog]

9 hours ago, Rusty_OToole said:

And how exactly do we do that?

What was once made by the hand of man can again be made by the hand of man..........Bob

[B Jake Moran]

I've reached out with a general inquiry to an IH parts and museum business to see if the side glass pieces are even available.   I can do a lot, but heavy dents in the body, not the front clip where whole pieces can be replaced with non dented items, and broken specialty glass is a non starter since I don't care to work with unobtainium stuff.  

[TerryB]

Restorer32 had special curved glass made for either a Detroit or Millburn electric car his shop was restoring. You might want to shoot him a PM for information on how he got it done.

[John348]

Part "B" to this is the window gasket that the glass sits in, is that in good shape to be re-used or is it available anywhere? Even if you locate the glass that could create the next big head ache 

[Frank DuVal]

1 hour ago, Jack Bennett said:

That would not, in the classic car world, be a excessively expensive price for the glass considering I just replaced the front, two piece flat, windshield in a 1951 Plymouth and that cost $500.00 and some change.

WOW! We had both panes replaced on a 1950 Plymouth in about 1981 and it ran $50 each piece. Pretty easy to cut flat laminated glass. Was there an expensive reproduction gasket(s) involved?

[Bhigdog]

2 hours ago, Jack Bennett said:

Hi Bob. I’m betting that is true. Perhaps the $5000.00 included the cost of making a template to bend both pieces, and was added to the cost of the first to simplify accounting for the labor and materials involved in its making. Considering that, the first glass only cost $250.00 and the template cost $4750.00 to make.

Now, to Un-BS the guy who made the glass, I’d call him back and say I needed a couple of more pieces of glass, identical to the pieces you just had made.

Since he now has a newly made template for the glass, and the $4750.00 cost to make one is now mute, the two pieces should run about $500.00 plus S&H.

That would not, in the classic car world, be a excessively expensive price for the glass considering I just replaced the front, two piece flat, windshield in a 1951 Plymouth and that cost $500.00 and some change.

Yes, his explanation was the first piece included the cost of the special tooling. After the tooling was amortized by the first piece the subsequent cost was material and labor. I did not think to ask him if he got the tooling. I expect so but maybe not.......Bob

[Restorer32]

3 hours ago, TerryB said:

Restorer32 had special curved glass made for either a Detroit or Millburn electric car his shop was restoring. You might want to shoot him a PM for information on how he got it done.

It was actually a 1918 Rauch and Lang. We needed 4 pieces of curved laminated glass per the client's instructions. We found a place near Philly that did curved architectural glass. We had to pay to have 3 molds made. One of.the pieces could just be flipped over. Total cost was $5000. We retain ownership of the molds in case anyone needs these windows in the future. Now that we paid for the molds the windows would cost maybe $3000 for.the 4.

[B Jake Moran]

10 hours ago, John348 said:

Part "B" to this is the window gasket that the glass sits in, is that in good shape to be re-used or is it available anywhere? Even if you locate the glass that could create the next big head ache 

John

It is.  I am sure it's hard and I would have to be careful in removal but it may be reusable.  

[Don Jr.]

Hi for more thought, I worked for a large corporation. I was involved in a project that required bending glass. Our glass blowers and toolmakers made a fixture from graphite. Then the glass was placed on top of the fixture inserted in an annealing furnace and programmed to ramp up to softening temperature. We raised the door to peek in and the glass was sagging into the fixture. After the glass settled into the fixture the temperature was ramped down overnight. The next day we opened up the furnace and we had a replacement curved glass. Thinking of a large side glass,  you would need a large fixture made (cost of material, and available machining time). Sagging the glass that large would then need quite a large annealing furnace. So yes making one very expensive but making more to sell would possibly offset initial setup charges. Hope this helps. We started with 12 glass blowers in a big shop area early 1970's and ended up with one person by 2012. Very sad as these men and women were extremely talented people.  Guess it is becoming another lost art. I am glad I was exposed and worked with these great individuals.

[Gary_Ash]

I also tried the graphite mold for bending some glass in a furnace back in the 1970s.  It turned into a giant Weber barbecue when the graphite burned, so we eventually learned to flow nitrogen gas into the furnace.  Ceramic molds work much better but are more difficult to make to precise shapes.  We eventually contracted with Corning Glass Works to make parabolic-shaped glass using pyroceram (Corning ware) molds.  These days, however, if you want glass bent in only one plane, there are lots of companies with the right technology who can do it without high tooling costs.  The difficulty begins when you want glass with 3D curves, then steel or iron tooling is needed. 

Here is one company that bends lots of glass, including some for cars:  https://www.curvedglasscreations.com/

 

See this YouTube video for examples of single plane bending:  

 

Here's how a full windshield is made with 3D slumping and lamination:

 

Edited September 11, 2022 by Gary_Ash (see edit history)

[Bhigdog]

I was wondering what a suitable material would be for the mould. Graphite makes perfect sense. Easy to work, smooth, and hi temp resistant....bob

[Restorer32]

For the windows we had made steel molds were used.

[Bhigdog]

11 hours ago, Gary_Ash said:

 

See this YouTube video for examples of single plane bending:  

Thanks for that, Gary. Very interesting. Totally different than what kind of mold I thought would be required, at least for 2D curves. If it were me and I needed the glass I think I would fab up the mold/form myself, assuming I could find someone to do the actual bending/annealing..........Bob

[TTR]

On 9/8/2022 at 10:52 PM, Ozstatman said:

Forum member TTR says he makes windscreens. Maybe he can provide some advise?

Yes, I have over 25 year experience producing curved, including compound shape windshields, rear windows and side glass for custom, obsolete, one-off, unique, small production applications. Have been commissioned 

to do many for cars shown at GNRS, Pebble, etc.

 

Creating a template, should no existing glass be available for one, can be more complex than most realize.

Some of the custom fabricated templates clients have provided in attempt “to save money” have been beyond mind boggling with countless hours/days/etc spent on something completely unusable, while some have been “sort of close”, but if a a mold or an actual glass were to have been made off them, they wouldn’t had fit even close.

 

Bottomline: Any custom shape, curved windshield, side or rear window can be created or replicated, but not necessarily inexpensively.

 

[Bhigdog]

3 hours ago, Bhigdog said:

Thanks for that, Gary. Very interesting. Totally different than what kind of mold I thought would be required, at least for 2D curves. If it were me and I needed the glass I think I would fab up the mold/form myself, assuming I could find someone to do the actual bending/annealing..........Bob

Or maybe not.......Bob

 

35 minutes ago, TTR said:

Creating a template, should no existing glass be available for one, can be more complex than most realize.

Some of the custom fabricated templates clients have provided in attempt “to save money” have been beyond mind boggling with countless hours/days/etc spent on something completely unusable, while some have been “sort of close”, but if a a mold or an actual glass were to have been made off them, they wouldn’t had fit even close.

 

[Shootey]

I just got my copy of the Griot’s Garage catalog. On page 3 they talk about a restoration shop specializing in 4x4’s. In the picture was an international Suburban. Perhaps they know of parts suppliers. See attachment for info. 

[Guest]

A friend of mine tried to get some Chrysler 300 windshields with the wrap around top reproduced and PPG's comment was  "we couldn't make them consistently when we made them when they were new, we broke as many as we made!" BIG answer NO!

 

  (They are available now in a modified version)

 

[TTR]

18 hours ago, Roger Walling said:

A friend of mine tried to get some Chrysler 300 windshields with the wrap around top reproduced and PPG's comment was  "we couldn't make them consistently when we made them when they were new, we broke as many as we made!" BIG answer NO!

 

  (They are available now in a modified version)

 

I’ve been producing and selling them to hundreds of cars on every continent for over 25 years now.

Mine are generally considered having far superior quality and fit than OEM (which were originally made by PPG).

 

And yes, there are cheaply made (China ) alternatives with less than adequate fit and form available at lower prices, but what kind of true antique car enthusiast would abuse their pride and joy installing something like on theirs that is beyond me.

Edited September 13, 2022 by West Peterson (see edit history)