Casein Broke just sitting in case???

[PrinterTom]

So I have a very nice Imperial Bamboo fountain pen in a display case on my desk. I was made by a member 5 or so years ago. I came into work today and the casein looks like it exploded???? Does casein expand and contract to the point of exploding? :frown::frown:

 

[brownsfn2]

Did it have a CA finish on it? Casein has been know to expand and contract and if it has a finish on it then it can't "breathe".

 

[PrinterTom]

I can see it on the tube side but I'm having a hard time seeing the CA on the outer side of the blank

 

[brownsfn2]

It is really a strange problem. I am not sure about your climate but we have had some really cold dry weather here. Maybe it is a result of that. Seems extreme though.

 

[PrinterTom]

The pen never left my office. Its in a climate controlled area

 

[brownsfn2]

Must be a jealous coworker. It is really strange. Can you post a picture?

 

[PrinterTom]

image

Please see the picture

 

[ed4copies]

The pen never left my office. Its in a climate controlled area

Many companies now turn the heat off or down significantly over the weekend---it may not be as "climate controlled" as you would assume.

 

[brownsfn2]

Wow. I thought maybe you meant cracked. You really did mean that it blew up. That is really unusual. Aside from having CA on the outside of it I can't think of what else the problem would be.

 

[PrinterTom]

The top you can actually see how much it shrunk at the top and bottom off the pen

 

[PrinterTom]

The pen never left my office. Its in a climate controlled area

Many companies now turn the heat off or down significantly over the weekend---it may not be as "climate controlled" as you would assume.

We are a manufacturing company who runs 24/7 365. It stays the temp unless the unit breaks.

 

[SteveG]

The top you can actually see how much it shrunk at the top and bottom off the pen

It looks like it was a very nice pen, and I am sorry that it is now just bits and pieces!

As mentioned by PrinterTom, it is possible to see on the cap, how much lengthwise shrinkage had occurred. Since the same likely happened around the circumference of the pen, it would explain the resulting self destruction. It is amazing that it took so long for it to happen, but is a cautionary lesson learned. I live in Hawaii, and experience relatively higher humidity. So my rods of Casein could potentially exhibit this same problem. I am not sure how soon I will get to this, but I think I might try to do some tests to see if I can observe any dimensional change by drying the material I have on hand. I do know that typical equilibrium moisture content of hardwood lumber is about 13% in my shop, and that number will go lower if the wood is moved to dry areas of the country and/or is located in a climate controlled environment. I wonder if anyone already knows any data relating to dimensional stability for Casein?

 

[KenV]

Tom - One of the concerns of conservators of collections of wood turned objects is that CA glue is turning out not to be archival. CA glue gets progressively more brittle over time and does not handle shocks well as it gets old. Most of the ages I have heard about are decadal.

The failure of the glue joint between the tube and the casein shell is clear. What cannot be seen in the photos is where the failure is occurring. It could be in the glue, at the surface of the casein or at the surface of the tube.

Casein is a tricky material to work with and has many known weaknesses. One study on ways to improve its performance describes the objectives "..... in order to improve the film-forming defects of casein such as hard, brittle and excessive moisture absorption performance, etc."

Under high magnification you may well find well find that failure is at the casein - glue interface.

Any chance that the pen/box was dropped or jarred hard??

 

[Kragax]

Or somebody was playing with it, dropped it, and put it back.

 

[bobleibo]

Or somebody was playing with it, dropped it, and put it back.

That's what I was thinking. After it sitting there with no problems for 5 years, to suddenly have it "explode" seems a bit suspicious.

 

[PrinterTom]

No I don't think so because there were little pieces that were on the underside of the case that couldn't have been placed there...too many small pieces.