Mb 346 - Is This Crazing?

[siamackz]

A friend has given me this rare 346 for restoration. It has many problems, only one of which is the celluloid wear.

 

Question - is this crazing in the picture below?

Edited May 13, 2018 by siamackz

[Charles Skinner]

Have you ever wondered when and why the word "issues" replaced the word "problems?" C. S.

[siamackz]

Have you ever wondered when and why the word "issues" replaced the word "problems?" C. S.

Nope but I learned something today and made a correction, so thanks

[CS388]

Is it on the inside of the barrel? Or the outside?

[siamackz]

Is it on the inside of the barrel? Or the outside?

It doesnt feel different to touch from the rest of the barrel. So I feel like its on the inside. I am wondering if I should take some micromesh and see what happens if I run over it?

[CS388]

Do you mean micromesh the inside of the barrel?

If the crazing is on the inside - and you've got it apart, It could be a good first investigation.

It would be nice if they were just stains (eg). Fingers crossed.

 

The only time I've seen decay, it was on the exterior of a barrel and it was crumbly. Any abrasive paper pulled 'bits' out of it. (This was on a c1930's no-name pen). Certain manufacturer's models were more prone to it, from what I've read, but I've never heard much mention of it on MB pens.

 

Here's hoping it turns out to be something simple.

Good luck.

Edited May 15, 2018 by CS388

[niksch]

Nope but I learned something today and made a correction, so thanks

 

Well, I'm glad you have a sense of humor.

[siamackz]

 

Well, I'm glad you have a sense of humor.

While I have you here, can you tell me your view on whether this is crazing or not?

[siamackz]

Do you mean micromesh the inside of the barrel?

If the crazing is on the inside - and you've got it apart, It could be a good first investigation.

It would be nice if they were just stains (eg). Fingers crossed.

 

The only time I've seen decay, it was on the exterior of a barrel and it was crumbly. Any abrasive paper pulled 'bits' out of it. (This was on a c1930's no-name pen). Certain manufacturer's models were more prone to it, from what I've read, but I've never heard much mention of it on MB pens.

 

Here's hoping it turns out to be something simple.

Good luck.

Thanks, let me see more closely

[Ron Z]

Crazing is a changing of the color of the celluloid which fluoresces, takes on a somewhat transparent appearance, and gets grainy. As the decay advances it breaks down into what resembles granulated sugar. In the more advanced stages the material literally crumbles.

 

Its hard to tell for certain from the pictures, but to me it looks more like the micro bubbles that form in the celluloid when a pen is repaired. A layer of clear celluloid made using solvents to make a slurry is applied to the damaged material, then sometimes the bubbles form as the solvent evaporates out of the material. It is unpredictable, and difficult to overcome. Its also quite common when the repair is done by someone who isn't experienced in celluloid repair. Its as much art as it is science.

[siamackz]

Crazing is a changing of the color of the celluloid which fluoresces, takes on a somewhat transparent appearance, and gets grainy. As the decay advances it breaks down into what resembles granulated sugar. In the more advanced stages the material literally crumbles.

 

Its hard to tell for certain from the pictures, but to me it looks more like the micro bubbles that form in the celluloid when a pen is repaired. A layer of clear celluloid made using solvents to make a slurry is applied to the damaged material, then sometimes the bubbles form as the solvent evaporates out of the material. It is unpredictable, and difficult to overcome. Its also quite common when the repair is done by someone who isn't experienced in celluloid repair. Its as much art as it is science.

Thanks for sharing, Ron! Is this repairable, in your opinion?

[Ron Z]

That's really hard, actually more like impossible, to say without seeing the pen. I've been doing celluloid repair for well over a decade, and many times still find this to be a challenge. Sometimes I can get rid of the bubbles, other times new ones appear while working on the spot. It depends on the pen and the celluloid. Some celluloid, and some colors even within the same brand are more vulnerable than others.

[siamackz]

I took a closer look a with my loupe under good light and it seems like the round spot has cracking like a shattered windshield around it. Very much like crazing. Any way to slow the process down?

[CS388]

If it really is celluloid decay, I don't think it can be stopped?

Until you are sure, keep it away from your other pens, as it can spread.

 

The round spot looks to have scratch marks over it? Could it be a result of an impact?

And, as Ron Z points out, could be old bubbles on the threads?

It seems so local to a couple of threads, I'm hoping it's just residue from some old glue, or sealant etc.

 

Still hoping it's fixable - but, if it is decay, you have to bin that part, quick!

 

Good luck.

[Ron Z]

When liquid celluloid is applied to a divot in the surface of a celluloid barrel, and done either too thick or in too many layers too quickly, the material can crack as the solvent evaporates out of the celluloid. Thin layers, with plenty of time between layers for it to cure, works best.

 

Trying to solvent weld/fill decaying material often exacerbates the problem and may accelerate the decay.

[siamackz]

Thanks guys!