Donmetal vault doors

[wylk]

From roughly 1921 to 1930 Mosler marketed a vault door construction they called Donsteel (or, sometimes, Donmetal). The door was a sandwich of steel with a copper layer that would draw away the heat of a cutting torch, making it an ineffective tool. This was briefly discussed in another thread ("Old NYC banks get a new life") but I thought I'd start a new thread since Donsteel was just a tangent to the original thread.

I ran across a 1949 advertisement for Conoco motor oil that references Donsteel, but not by name, as an analogy to the extra protection of their oil. It seems strange since Mosler hadn't been marketing Donsteel for nearly twenty years but somebody in Conoco's advertising department must have been impressed by the idea. Maybe he was an old safecracker.

Here is the image from eBay of the ad (the eBay item ID is 230750362144 though it is about to expire), plus an example door at the Courtyard/Marriott in San Diego.

[wylk]

Here's another example, part of the plaque is readable in the full-sized image. Does anybody know where this door is? I've run across suggestions it might be in Japan (http://www.flickr.com/photos/soul72/54067048/). This image also shows up in a lot of places as a "stock" image.

[Dean Nickel]

Against an Oxy/Acetylene torch it would be a good defense Against a thermal lance not so much. But then there were other defenses against that, AKA time locks and glass plates.

As with all security it was a layered defense.

[Doug MacQueen]

I can't remember the vault door in the Dollar Bank and doubt I took a pic but the building itself is one of the oldest around and the interior is like going back in time. I think I know where the other door is and if correct is no longer a bank. Struggling to remember the name of the building which was quite large but not a sky scraper. Regarding the Donsteel, it is somewhat strange that the test was on a block of the metal whereas the doors have it wrapped in considerable thickness of copper or copper heavy alloy. If it really was that good, why bother with the copper. I have an incomplete Xerox copy of a Mosler Donsteel booklet put out 1923 but it has really bad photos and doesn't go into any real detail about the Donsteel. I also found several patents from the early 20's for burn resistant vault linings that sound suspiciously like Donsteel, using magnesium and aluminum oxides. Doug

[wylk]

I can't remember the vault door in the Dollar Bank and doubt I took a pic but the building itself is one of the oldest around and the interior is like going back in time. I think I know where the other door is and if correct is no longer a bank.

Dollar Bank still lists the building, 340 Fourth Avenue in Pittsburgh, as a branch (http://www.dollarbank.com) though of course they might occupy less space these days and have leased part of the interior including one of the vaults. The bank has an entry on Wikipedia, http://en.wikipedia.org/wiki/Dollar_Bank, the building was opened in 1871. I can imagine the interior is quite unique and historic. A short news item regarding the stone lions out front: http://triblive.com/business/headlin...#axzz2JU3loxkj.

One of the pictured doors is probably the money vault, and the other is the safe deposit vault? I'm still assuming both images are from the same bank at the same time. The larger picture is stamped The Mosler Safe Co. so I would tend to believe their description over Dollar Bank's.

[Doug MacQueen]

Google patents "Coles and Donaldson"

[wylk]

Google patents "Coles and Donaldson"

Cool, that did show up quite a few, and they were assigned to Guardian Metals which was a Mosler company. I tried a search on http://freepatentsonline.com for an assignee of Guardian Metals and came up with a few more that did not have Donaldson's name.

[wylk]

Here is a somewhat unusual Donsteel door in that it has two layers of copper, not just one. Plus it is impressively beefy. Notice the bussbar-style wiring under the glass and the contacts at the top of the door for connecting to the alarm system. This door is part of the former state treasury in the Texas state capitol building in Austin, 1100 Congress Avenue. I believe this can be viewed during tours.

This image is from http://www.flickr.com/photos/27285679@N02/2544838527.

[Adrian Weber]

Hey Wylk thanks for this great information and for sharing that ad mate!
Is it in your collection?

I have information on armor being used by Bode Panzer and several drawings including a brochure but I can however not put it online here. Those doors are still in use in a lot a banks here in Germany and I can not risk putting such information online, sorry :(

[wylk]

It is confusing that Mosler described Donsteel/Donmetal as an alloy, when photos clearly show a sandwich construction. It may have been both. The steel layers may have been alloyed to improve torch resistance (by raising the melting point and/or improving thermal conductivity, for example) while the copper layer was an additional measure to improve resistance even further (plus it was a very visible feature to the customers and crooks alike).

Doug, could you post the patent numbers and scan the booklet?