BulbCollector Forums
BULB DISCUSSION BOARDS => Antique Bulb Discussion => Topic started by: Tim on October 30, 2003, 12:38:00 pm
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A reader wanted me to share these pictures in hopes of sparking some discussion of what I like to call transitional light bulbs. These bulbs could be described as those which exhibit features of two different manufacturing designs or practices. Two examples are pictured below.
The first picture shows an unusual Edison tipped bulb that is inside frosted. Normally inside frosted bulbs are not associated with those having exhaust tips. The second pictures shows the familiar 1890ish Edison long neck bulb, but look close. This bulb has squirted (looped) filament making it highly unusual compared to the more common hairpin shaped filament.
In my own collection I have a tungsten cage filament bulb, exhausted out through the stem in the normal manner of tipless bulbs from this era. The unusual feature is that the bulb also has a small protrusion, or "baby tip" on the top of the bulb, suggesting it's merely there for decoration. Perhaps people weren't quite yet ready for the new tipless bulbs?!
If you have any transitional bulbs that you would like to picture here or comment on then please do!
(http://www.bulbcollector.com/photos/insidefrosted.jpg)
(http://www.bulbcollector.com/photos/ntloop.jpg)
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Tim
Kilokat's Antique Light Bulb Site (http://www.bulbcollector.com)
Mountain Dew Collectibles, Volume I (http://www.dewcollector.com)
[This message has been edited by tim (edited November 02, 2003).]
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Hello Tim,
What a coincidence, I use the same term, "transitional" for identifying this kind of bulbs! In fact, I posted a page about one of my transitional bulbs last June, have you seen it? If not, here's a link (http://sfe-emul.tripod.com/transitional-bulb.html).
Speaking about the b.i.n. auctions from tiqman... I had a low amount of cash (as always!), so I picked just one. It's funny how all (or most?) of his auctions went to all different buyers!
I also have one of those Mazda bulbs with the mini-tip (but it doesn't work); I believe this little tip is a "mounting point" for the glass tube through which air is evacuated and then sealed off. While the glass was still hot, the glass tube would be put over the mini-tip, and then it would puncture the mini-tip through vacuum pressure. This probably means that the mold used for the mini-tip bulbs and the tipped bulbs was the same one, and that the new 100% tipless molds had not been shipped yet to the factory. This is just my opinion, I don't know if it really was that way.
-Yoshi
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Hey Yoshi,
Thanks for the reply and the link - very unusual looking bulb and another good example of what I was talking about. Does anyone else have more odd transitional bulbs?
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Tim
Kilokat's Antique Light Bulb Site (http://www.bulbcollector.com)
Mountain Dew Collectibles, Volume I (http://www.dewcollector.com)
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Hi
I am puzzled as to what is meant by transitional, pipless (or tipless) bulbs were being made in 1900 and pip top bulbs still being made as late as 1930. That is far too long a period to consider transitional - or am I missing something here?
Also, as I understand it, the pip is the remnant of the exhaust tube and while normally on top, could be at the bottom (hidden by the cap) or even on the side (Bulbs intended for use horizontally - I will be posting a full-size pic of that from the VVG catalogue eventually but it can be seen now on the left of the poster at http://www.ysartglass.pwp.blueyonder.co.uk/Bulbs/vvg/vvga5.htm (http://www.ysartglass.pwp.blueyonder.co.uk/Bulbs/vvg/vvga5.htm) ).
Some de-luxe bulbs had a pip ground and polished off too.
Frank
[This message has been edited by debook (edited November 08, 2003).]
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Frank,
My examples are of American made bulbs which follow different timelines in regards to design and manufacturing practices versus those made in Europe which I think you?re referring to. I guess I don't know how to explain this any better than I have above. The pictures posted (and Yoshi?s link) illustrate this subject pretty well I thought. If someone else can clarify this better feel welcome to jump in...
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Tim
Kilokat's Antique Light Bulb Site (http://www.bulbcollector.com)
Mountain Dew Collectibles, Volume I (http://www.dewcollector.com)
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The small fake tip you have on the top of some bulbs is, I believe, just a relic of the way they used to be made rather than for decoration.
The machines which attached the exhaust tube to the top of the bulb originally used to do this on simple smooth-ended bulbs. But it was found that a neater join can be made, and the process done more quickly, if a protruberance was added to the crown of the bulb at the time the whole thing was blown. I estimate from about 1910 onwards, bulbs were blown in the mould with this small tip already on the glass. I have photos of the British Mazda lamp factory in 1911 and some production areas were using pre-tipped bulbs, others still had smooth ends.
If you a buy a 150W European-made ordinary GLS lamp today you can still see evidence of this if the bulb was blown at the Sylvania glassworks in England. (Glass from Sylvania is 68mm diameter, glass from Philips is 65mm diameter for 150W lamps). The Sylvania 68mm moulds are ancient and originally used to be used for making tipped bulbs. The area for blowing the tip on the bulb was filled in probably about 1925 but it was not fully removed, and even today you can still see evidence of its presence on finished bulbs. There is a very slight tip still there, maybe only about 0.5mm tall but very definitely there!
James
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That clarifies it and adds to my knowledge - thanks guys.
Was there really much difference in the timelines of developement between US and Europe? Surely with Edison and Swan combining their patents and later with the general licensing of patents shortly after filing in one or the other contintent, there was very little lag.
Sure there were developments in some countries that did not migrate but most of the major ones appear to have done so.