Topic: Real Imperial Glass Phoenix or copy?

[krsilber]

Molds were retooled, but that wouldn't account for a change like the position of the head.

May I ask why not?
Regards,
Marcus

But of course you may!    Frank already said it:  "Retooling a worn mould is unlikely to change the overall geometry..."  Retooling involves removing material, but so far as I know you can't add material to a mold, so you can't change the position of something large like the head.  Frank went on to say, "...but it is feasible to replace one or more parts of a mould completely as deemed necessary" and that's a good point I hadn't thought of.

I don't know why they couldn't make multiple molds that are very nearly identical.  You could either use the original model from which the first mold was made, or make a model of an existing piece to base the new mold on.  In reproductions of Depression glass it's often the surface details that are different from originals, not the shape as a whole (though that can change, too).  The details were cut or etched into the mold after it was formed, so it was harder to copy them accurately.  New molds may also have seams in different spots.

It is not wise to assume that a single mould was used, as popular lines might require multiple moulds to be used concurrently and each mould would have differences and some of these could be significant.

From the years that I was active in a Depression/Elegant glass forum and editor of part of the associated image gallery, I don't remember any examples of items that had multiple significantly different forms or dimensions that weren't reproductions.  I'm sure there are some, but they're uncommon.  It's pretty amazing, really, how little change there was even in popular lines that ran for a long time.  (This may not apply to items that had post-mold manipulation like applied handles...or the position of a bird's head and neck.)

Look at the Cambridge swans, they can be dated roughly by their differences I believe.

(Christine)
I just found a post in that forum that talks about Cambridge Type 1 and Type 2 swan molds; could that allude to the differences you're talking about?  Incidentally, there's a photo of a swan mold here that I took at the Cambridge Glass Museum, at the top of [LINK REMOVED] an article that talks about the movement of molds from company to company (or other organisation).  (The photo wasn't so blurry when I took it!  Cool mold, though.)

[Mod:  Links to clicksnipwow removed as site is no longer connected to glass. Please visit http://chataboutdg.com/forums/ and use the search function instead]

[Frank]

It is possible to add material from a mould, cut out a piece and put in a new chunk. While it would certainly be done in some industry, I have no idea if it is/was done in glass moulds. Originals models are often made of wood and cast made from that. Most impressive is seeing masters that are carved for moulds, removing a stage in the process. I have no idea if the castings were made from wax or sand positives. No doubt all of the possible mould making techniques have been used for making glass moulds.

A good way, for American's, to see the impact of multiple molds for a single shape is to pick a particular OI (Owen-Illinois) container shape that have fully documented mold numbers in their catalogs (to facilitate reverse ordering). For examples you will find the mold numbers A-381, A-406 & A-410 on the 2oz Argylle Bull Neck Panel shown here. (US spellings used) (Data and images, not yet on-line, courtesy the Glass-Study).

Many decorative items may well only have one mould, it is all dependant on the rate of production needed.

[krsilber]

There's an article on the National Cambridge Collector's site about the three different types of swan.  In all but the 3" size the different types were reworking of the same mold.

The reason I was over there, though, is an interview with a former Cambridge mold maker.  The original models were made of wood, as Frank said, then plaster casts made of them.  Only the exterior details of the mold were done by the casting company; the interior detail was at Cambridge using hammer and chisel.   "A small item like the Nude stem took three to four weeks to chip out with the hammer and chisel."  Interesting article.

The molds obviously took a long time to make, which would explain why they were retooled whenever possible rather than having new ones made.  The retooling is one reason why sizes (diameter, etc.) are so imprecise and variable.  Apparently some molds required specialized tools to operate, and even when a mold went from one company to the next, if they didn't have the right tools they couldn't make it work.

It is possible to add material from a mould, cut out a piece and put in a new chunk.

  In a cast iron mold?  That will withstand the heat and pressure required in the glass pressing process?  Maybe.

Most impressive is seeing masters that are carved for moulds, removing a stage in the process.

Do you mean for turn molds, and other molds for blowing?  Heisey used wooden molds at least in their early years; they probably switched to iron molds later.

[Frank]

Drat I missed out 'negative', i.e. the same as the mould. Some of the best mould makers were American.

The engineers at glassworks are often the unsung heroes.

[deco.queen]

Just found this when reading another thread, http://www.geocities.com/SoHo/Den/3255/, I didn't know Tiara made it.

[Ohio]

Lancaster Colony ended up with this mold & made them for Fostoria outlet stores & Tiara. IG reissued them from 1964-66 & the 65-66 reissues had the neck moved slightly downward, less upright. Also IG made the 64-66 reissues in multiple colors, more than is listed in some references so you cannot go by color. Below is a Periwinkle Blue Phoenix from IG in 1966. Ken