We are restoring the windows on Southern Pacific 60' "Harriman" coach S.P. 1949, built by Pullman in 1910. This car has 4' 3" wide windows. Each new wooden sash with 3/32" type 2 laminated safety glass weighs about 35 lbs, so a counterbalance is needed for safe window operation. The carbody is still equipped with the original slotted bronze (brass?) brackets inside the walls above the window openings. Each bracket has two open-top slots: one for the for roller sash balance, and one for the curtain roller. We need the roller sash balances. Does anyone know of a source?

Background:
Openable windows on heavyweight passenger cars were originally equipped with sash balances. Sash balances act as counterweights. This makes it easier to open the window, prevents it from crashing down like a guillotine if sash locks (pinch latches), which racks the windowframe joints and can injure a passenger.

Buildings typically used a lead weight - sash cord - pulley system on each side to counterweight the window sash. But this would rattle incessantly on a moving railroad car. So railroad car sash counterbalances used springs instead.

There are two basic types of RR car sash balances: The first type looks like a tape measure, and unreels a steel band pulling against a spiral spring. These are still made by Pullman Mfg. http://pullmanbalances.com/

The second type of sash balance has a roller (like a pull-down roller window blind) with flat chain or flat cloth straps wrapped around each end. The lower ends of the chains or straps are attached to the window sash. As the window goes down, it pulls out the chains/straps, which is resisted by a torsion spring inside the roller.

Does anyone have a source for roller window sash balances?

If not, I am thinking about adapting the torsion-spring-equipped rollers used on pull-down roller shutters. Rollac makes these, maybe others as well. See section 5.8 of their parts catalog, 40mm diameter roller: http://www.rollac.com/Parts_Catalog/Section%2005%20-%20Gears.pdf

Any suggestions?
Thanks! - Doug Debs
Niles Canyon Railway

Another reputable manufacturer of "tape-measure"-style sash balances is Acme Duplex, in San Bernardino, CA: http://www.acmeduplex.com/index.htm

Also, if you has an original roller sash balance from a railroad car, we would greatly appreciate borrowing it. Any length is OK.

- Doug Debs

I am not sure about the origin of the Pullman sash balances. Pullman Manufacturing is currently located in Rochester, New York, and says its been around since 1886. It supplies sash counterbalances to house renovators and makes other products.

I ran into the firm when for work I had to get a replacement counterbalance reel (industrial style) for the lid of a Ulrich Planfile (a fireproof drawing cabinet). Ulrich used to stock replacement reels, but now refers to its supplier. I found Pullman's staff to be helpful both via email and on the phone.

I got the window thickness wrong in my first posting. It is 7/32" thick category 2 laminated safety glass, which has a .030" (nearly 1/32") thick PVB plastic layer between two 3/32" thick glass layers.

- Doug Debs

I did run across sash balances in the 1922 Car Builders' Cyclopedia. There are a couple of versions illustrated and they look reproduceable based on the illustrations and engravings I looked at. Certainly a style of rotary spring like that used in shades looks most adaptable, especially if you can get the correct strength spring or combination of two. Depending on sizes, the Pullman sash balances in pairs look to be a simpler option.

Let us know what you decide on and how well it works, please.

Best,
Mike