New batteries no longer fitting old flashlights

Dr. Jones

Newly Enlightened
Joined
Oct 7, 2023
Messages
162
Location
Princeton, New Jersey
I was doing a little digging (metaphorically speaking) on the standards for dry cell battery sizes, as it's been my experience that a lot of the older vintage flashlights, particularly those from the 1930s and earlier, have clearance issues with some of the modern batteries. Went to the Energizer battery site which provides various specifications and industry standards for their batteries, and also found some old National Bureau of Standards (now termed the National Institute for Standards and Technology) documents online from the 1930s which revealed some interesting information.

I have an Eveready "Daylo" flashlight, circa 1915-1920, and it requires two 'C' cells. However, currently-manufactured alkaline 'C' cells that I've tried are too tight a fit; they will go in, but they have zero clearance with the slide switch, which binds and will not move with them inserted. According to this NBS document from 1937, page 3, Table 4:

https://nvlpubs.nist.gov/nistpubs/Legacy/circ/nbscircular414.pdf

…the nominal diameter of a 'C' cell in 1930 was 15/16" diameter, or 0.938", with some unspecified wiggle room either side (hence "nominal"); I have some old LeClanche cells that are just about that diameter, and they fit perfectly. Now compare this figure to the current specification according to Energizer, here:

https://data.energizer.com/pdfs/e93.pdf

which I'm assuming is pretty well the current industry standard; the diameter now ranges for 0.098" to 1.031", considerably greater than the old figures, and is apparently enough of a difference to bedevil collectors of old flashlights to no end.

However, things get murky rather quickly.

According to this even earlier NBS document, from 1930, on page 3, Table 3:

https://www.govinfo.gov/content/pkg...VPUB-C13-9f2dbdfb173943fb903f35c176e26f9b.pdf

…the diameter of a 'C' cell can vary from a minimum of 31/32", or 0.969", to a maximum of 1-1/32", or 1.031"! What happened to the supposedly-nominal diameter of 0.938" given in the 1937 document? It would appear that the NBS couldn't settle on a specification.

If the above is any indication, it's apparent that there were no hard-and-fast rules regarding battery size long ago, and as long as a given manufacturer's batteries fit their own and possibly other manufacturer's flashlights, all was well. It does, however, appear from a perusal of my own battery collection that the diameters overall seem to have slowly increased as time went on.

I'd like to hear your thoughts and experiences on the matter; do you have any older flashlights that have problems with the dimensions of current alkaline batteries?
 
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Dr Jones, one thing I noticed was the rubber tube lights seemed to have larger ID than brass ones prior to the 1930's, at least for D cell lights anyway. I only have a small number of C sized lights from that period so I don't have much with which to comment about that size. Those C size I have both seem to be about the same, as in only carbon zinc Rayovacs and Eveready cells will fit them. In other words I can fit alkalines in the D size vulcanized rubber barrel kind but not the metal barrel kind.

In the early days of flashlights most dry cells were AA sized wrapped in electrical tape and a cardboard sleeve to print the brand name on.
The vest pocket light for example had a special battery that was the 2aa wrap. 2D flashlight? A cardboard case 2 cells long. 3D, 3 AA batteries end to end wrapped in electrical tape with a cardboard wrap.

Later batteries like C and D cells were called "uni-cells".

There used to be a great resource called flashlight museum dot com but it's gone. Gotalight dot net is still going. David has lots of information along with his friend Steve Gitterman who has an extremely large collection of flashlights and table lights from the first half of the 20th century. I gained much of my know how from those fellows and a book by Bill Utely called "flashlights", which is an extremely detailed history of Eveready (and Daylo)
An interview with Mr Utely
 
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I am already having much success running a '3 C/D' Mag bulb with a single Mag 18650 in an adapter in 2xC class lights. I wonder if I can't just run 2, 3, 4, etc. CR123 with some bulb meant for double the amount of C or D cells?

I don't yet comprehend what amps and watts mean and I'm slowly getting a feel for what PR type bulb goes where. Having a nice consistant out put beats changing Carbon Zincs daily in real use to maintain decent levels of brightness. Both of which are preferable to having the slowly dimming alkalines that are likely to trash a light.
 
There used to be a great resource called flashlight museum dot com but it's gone. Gotalight dot net is still going.

If you remember the URL, the wayback machine may still have some/all of the files, although you may have to look through several different archives. I had to do this when hhscott.com sadly disappeared.
 
Dr Jones, one thing I noticed was the rubber tube lights seemed to have larger ID than brass ones prior to the 1930's, at least for D cell lights anyway. I only have a small number of C sized lights from that period so I don't have much with which to comment about that size. Those C size I have both seem to be about the same, as in only carbon zinc Rayovacs and Eveready cells will fit them. In other words I can fit alkalines in the D size vulcanized rubber barrel kind but not the metal barrel kind.

In the early days of flashlights most dry cells were AA sized wrapped in electrical tape and a cardboard sleeve to print the brand name on.
The vest pocket light for example had a special battery that was the 2aa wrap. 2D flashlight? A cardboard case 2 cells long. 3D, 3 AA batteries end to end wrapped in electrical tape with a cardboard wrap.

Later batteries like C and D cells were called "uni-cells".

There used to be a great resource called flashlight museum dot com but it's gone. Gotalight dot net is still going. David has lots of information along with his friend Steve Gitterman who has an extremely large collection of flashlights and table lights from the first half of the 20th century. I gained much of my know how from those fellows and a book by Bill Utely called "flashlights", which is an extremely detailed history of Eveready (and Daylo)
An interview with Mr Utely
Thanks tons for all the information and background, the interview and the reference to the Flashlight Museum; appears that the wayback machine has it all saved. What a resource! I'd post a link to it, but that's a big no-no on some forums belong to; wonder if it's acceptable here.
 
IMG_5641.jpeg

Check this out everybody!!

One day a box with Rayovac carbon zinc batteries wrapped in an old looking sleeve showed up at my house.

Thanks Doc!!

What a great idea.
 
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