Cellulose dinitrate or pyroxylin... or ... how I learned to love the bomb

[Codger_64]

Here is a family portrait of some of my Kastor/Camillus pyrolene handled knives. A couple have slightly deteriated after six years in storage, but not terribly. One example with cracked handles is the one I experimanted with years ago while learning about this material. What sort of plastic is this? Scratch and sniff gave no clues, mild heat and sniff either. But when a flame was applied... Whoa nellie! It went up like a roman candle and was difficult to extenguish. Luckily I has a wet cloth and a cup of water to drop it in. But other than a bit of shrinkage, becoming a bit brittle (and flammable), this solid molded "cell" is pretty stable. Camillus used it in this molded "unbreakable staghorn type" material, as best I can tell, from about 1937 through 1941 or so.

The best article on cell I have read to date:

http://www.oregonknifeclub.org/celluloid_02.html

 

[InTheSticks]

Good info and thanks for the link

 

[Gevonovich]

Best "Title" yet, Michael!!

I don't think I'll scratch and sniff but I may try the Roman Candle bit

 

[MerryMadMonk]

When celluloid outgasses it can do this (same model knife for comparison):

It eats metal

And eats it pretty quickly

I keep my celluloid-handled knives stored away from my other knives and each celluloid-handled knife has its own storage space. I try to check on them at least weekly. Sometimes weekly is not good enough, though. Again, when outgassing starts it can destroy metal in a short period of time. I'd estimate it took about 2-3 days to do the damage to the knife shown above.

 

[Pipeman]

A couple of years ago I was grinding the last 4 inches of an old sharpening steel off to use as a spike in a war club I was making. The heat ran through the steel and the handle started pumping smoke then exploded into flames. I ran it to the door and threw it out into 3 feet of snow. It melted right through the snow and within a few seconds was ash. My basement was full of dense smoke up to my waist. That was the last time I messed with celluloid in the house.


Best regards

Robin

 

[Codger_64]

If you read the link, Dennis Ellingsen made some very salient observations and points. Cell is a unique material and like many materials has it's strong points and weak points. For one, makers back then never envisioned the knives surviving long enough to be deemed valuable to collectors. Then as now, cutleries were in the business for the money, not to make history, not to produce cutlery to be collected and cherished a half century or more later. The Remington study he referenced concluded the average lifespan of pocket cutlery to be three years or so. Historicly, makers depended on this obsolescence to keep the market active, to keep the public demand for new knives going. Cutleries make zero dollars on knives preserved for later secondary market resale.

Collectors as a market influence is a comparatively recent advent, certainly well within my own lifetime. Imagine GEC, Queen or Canal Street trying to survive on a modern market entirely composed of users today. They couldn't do it. Among the steadily declining population of users is a very significant portion who are just looking for a very cheap disposable "fast-food" tool. Thus the proliferation of imported cutlery, last century chiefly from Europe, now for the most part from the Pacific Rim.

So cell is what it is, a volitile, unstable early form of plastic. Some people, for good reason, reject it from consideration for inclusion in their collections. And some of us revel in it for it's historic value and beauty of appearance when it comes down through the years intact. And we accept the fact that it is not permanent. Like the bakelite dash and shifter knobs on my 1936 Nash Lafayette, my first car. Nash did not build it to last forever.

 

[MerryMadMonk]

A couple of years ago I was grinding the last 4 inches of an old sharpening steel off to use as a spike in a war club I was making. The heat ran through the steel and the handle started pumping smoke then exploded into flames. I ran it to the door and threw it out into 3 feet of snow. It melted right through the snow and within a few seconds was ash. My basement was full of dense smoke up to my waist. That was the last time I messed with celluloid in the house.


Best regards

Robin

I know it probably wasn't funny at the time, but that made me laugh Thanks!

 

[Alnamvet68]

If you read the link, Dennis Ellingsen made some very salient observations and points. Cell is a unique material and like many materials has it's strong points and weak points. For one, makers back then never envisioned the knives surviving long enough to be deemed valuable to collectors. Then as now, cutleries were in the business for the money, not to make history, not to produce cutlery to be collected and cherished a half century or more later. The Remington study he referenced concluded the average lifespan of pocket cutlery to be three years or so. Historicly, makers depended on this obsolescence to keep the market active, to keep the public demand for new knives going. Cutleries make zero dollars on knives preserved for later secondary market resale.

Collectors as a market influence is a comparatively recent advent, certainly well within my own lifetime. Imagine GEC, Queen or Canal Street trying to survive on a modern market entirely composed of users today. They couldn't do it. Among the steadily declining population of users is a very significant portion who are just looking for a very cheap disposable "fast-food" tool. Thus the proliferation of imported cutlery, last century chiefly from Europe, now for the most part from the Pacific Rim.

So cell is what it is, a volitile, unstable early form of plastic. Some people, for good reason, reject it from consideration for inclusion in their collections. And some of us revel in it for it's historic value and beauty of appearance when it comes down through the years intact. And we accept the fact that it is not permanent. Like the bakelite dash and shifter knobs on my 1936 Nash Lafayette, my first car. Nash did not build it to last forever.

It could have been worse if you owned a Nash Metropolitan; it was the first car crash that I was in, I didn't have a license yet, I was 14, and it was my best bud's father's car, which my friend "borrowed"..

 

[MarkPinTx]

Planned obsolescence aside, I kind of wonder if they even knew these materials would deteriorate so hideously.

 

[Codger_64]

Planned obsolescence aside, I kind of wonder if they even knew these materials would deteriorate so hideously.

Yes. The process for producing and cureing it for application to a knife handle was very exacting. Sometimes the process was rushed and cell was used before it was fully cured and the deteriation began sooner rather than later. Thus the need for storing cell in special outbuildings away from the factory. Look at how often early cutleries burned. It wasn't always because of accumulated oil and dust.

And an indication of this knowledge also is that as soon as alternative plastics were developed and made available, cutleries turned to those. One of the earlier alternative plastics was styrene. Delrin did not come onto the market until 1960. And when it did, much of the industry shifted to this more stable and inert plastic.