What are Case yellow handles made of?

airyq

airyq

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In one of the resources from Bernard Levine, the author states that Case yellow handles are made of celluloid. I read in another forum that the Case yellow handles are delrin.

Case yellow handles are just commonly described as composite, which doesn't reveal any thing at all apart from the fact that they are synthetic.

Is delrin a form of celluloid?

What are they exactly? My concern is the fumes said to be released by celluloid handles and its effect of other knives being stored together.

Also, there are several other makers with very similar looking yellow handles, eg. Camillus Yello Jackets, Eye Brand smooth yellow handles. Are these all the same as the Case yellow handles?

Would appreciate any info.
 
The old ones would have been celluloid (pre60's? Not sure). All the new ones are delrin.

And no delrin is not celluloid. The composition makeup is completely different.

No danger there.

Celluloid breaks down after time. The worst place you can store a celluloid handled knife is in a case, or closed in area. Its tends to accelerate the decomposition (and rust the blades). One way to tell an older celluloid handle is to see if the handles have shrunk. knives handled in it tend to decompose differently, as far as time, decompostion, etc. I have some that are only 7 years old that are rusting and the handles have already shrunk. Some say that the darker handled ones take longer to decompose (because of more fillers), but mine are all dark and have shrunk and rusted in just 7 years. If you think you have a celluloid handled one check and see if the handles are not fitting right (they appear to be shrinking, etc.). Chances are it is probably not. Also the area near the spine and top of the blade are the places that the celluloid knives tend to rust.

Hope this helps some.
 
Leatherbird, delrin is plastic.


very true! ping pong balls still are!!! Back in the mid 1800's when celluloid was invented they use to make billiard balls from it!!! Unfortunately, because they were being constantly hit, some actually "exploded", or so it is said.

Its is extremely flammable!!!
 
El Lobo, that was the article that I was referring to. Towards the end, the author states that he tested several brands and found them all to be celluloid. This was what got me worried.

Rev jch, thanks for the info. You have put my mind at ease. My Case yellows are all quite recent, post 2003.

Any idea about the other yellow handles?

Any way to tell when the knife is new? Apart from burning it. Waiting for the handle to shrink or the knife to rust may be leaving it a bit too late.
 
airyq said:
Any way to tell when the knife is new? Apart from burning it. Waiting for the handle to shrink or the knife to rust may be leaving it a bit too late.
Click to expand...

The only thing the article offers is smell.

Maybe if someone knows of a non-destructive test for nitric acid, it could be of some help.
 
Few companys make celluloid these days. Mostly you find it in German knives still. Case does make some, there have been some other limited runs of old knife patterns from different companies with celluloid, but as a whole its really not that common. Celluloid use to be cheap to produce, but it is not anymore (or so I have been told) due to the hazzards involved.

As far as telling if a handle is celluloid, aside from burning, you can see of the handle has shrunk. Of course this is providing that the knife is old and the handle has begun decomposing. If you handle a few celluloid handled knives you start to get a "feel" for them.
 
I emailed Case about the original question - "What are Case yellow handles made of?". I was curious myself. rev_jch is right - they're Delrin.

They also gave me some interesting history along with the answer, so here's the response I received:



Dear Ryan;



Thanks you for your interest in Case knives. There have been three yellow
cover materials used in Case history; celluloid, composition and Delrin.
Case began using yellow plastic in the 1920's and it was celluloid at that
time. The composition that is listed above was used from about 1945 until
1960 at which time we changed to using DuPont Delrin. I don't have much
information about the composition material other than it was easier to work
with than the celluloid. DuPont developed Delrin in the early 1950's and
patented the formulation in 1956.



Delrin is an acetal resin that was developed by DuPont in their efforts to
supply customers with tough heat resistant metal substitute. "Delrin(r)
bridges the gap between metals and ordinary plastics with a unique
combination of strength, stiffness, hardness, dimensional stability,
toughness, fatigue resistance, solvent and fuel resistance, abrasion
resistance, low wear and low friction. This quote is taken directly from
the DuPont Website explaining the characteristics of Delrin.



I hope I have sufficiently answered your questions. [Stuff about Case Collector Club]



Best Regards,





Rich Brandon

Engineering Manager

W.R. Case & Sons Cutlery Co.

[phone # & email removed for privacy]
 
I can add that the "composition" material used during the 50's was similar to celluloid in that it will easily self destruct. In fact, it may be worse than the older celluloid based on the numbers of each that I have observed over the years in a degraded condition.

The older pre-WWII celluloid had a bright glossy yellow color, the edge near the brass liner will be white; this is what collectors call the "white liner" as it refers to the old celluloid handles.

The 50's era "composition" was a much more muted color, the catalogs referred to it as "cream composition"....it was more toward a cream color rather than a definite yellow.
 
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