At least Shappire & Glass are not ideal materials for Pelikan M800

[VonPG]

This Pelikan Pen M800 is made of Optical Borosilicate Glass in body and Shappire in cap.

However, after I made this pen within 48 hours it just broken(I am a very careful people who never drop a pen on the ground for 10 years)

Maybe the only reason to explain it is that thread stroke was too long.

At least I know that Shappire & Glass are too fragile to make a endurable fountain pen. So I remove those materials in my transparent pen making :{

Luckily, a friend made a optium museum acrylic pen body with sterling silver clip for me as “backup”.

 

Some good transparent materials list in pen making

PEI(Pure)   

Acrylic(Optium Museum Rate)   

Pasmo Special Amorphous Polymer Resin(Speical Polycarbonate and it is totally different from normal PC plasitc)

Corning ULE Glass/SCHOTT Zerodur(Can be machined with diamond or other superhard tool knife)

[Honeybadgers]

wait, maybe I missed some context - did you make that out of ground borosilicate? HOW?!

 

My experience with lab glassware would tell me that you cut the threads way too fine as well. A coarser start would prevent a lot of the tightness that may have shattered it.

 

What makes you think synthetic sapphire wouldn't work? I can only imagine how outrageously expensive it would be, but there's a reason high end watch crystals are sapphire, and not borosilicate. Sapphire is quite impact and stress resistant. 

 

I wish pelikan's demos were made from proper acrylic. The injection molded plastic they used for the m205 demo, which I LOVE, just stains like a nightmare and scratches from being posted. 

 

And yet the acrylic barrel of my wing sung 698 that has been inked continuously for 4 years with everything from iron galls to baystate blue has NEVER stained.

 

[VonPG]

48 minutes ago, Honeybadgers said:

 

 

My experience with lab glassware would tell me that you cut the threads way too fine as well. A coarser start would prevent a lot of the tightness that may have shattered it.

 

What makes you think synthetic sapphire wouldn't work? I can only imagine how outrageously expensive it would be, but there's a reason high end watch crystals are sapphire, and not borosilicate. Sapphire is quite impact and stress resistant. 

 

I wish pelikan's demos were made from proper acrylic. The injection molded plastic they used for the m205 demo, which I LOVE, just stains like a nightmare and scratches from being posted. 

 

And yet the acrylic barrel of my wing sung 698 that has been inked continuously for 4 years with everything from iron galls to baystate blue has NEVER stained.

 

No, I made pen body from glass tube(sorry maybe i made some expression problem)

 

Thanks for your suggestion on thread processing. Anyway, I will try it later. 

 

Sapphire is a strong material but it is also weak at Anti-drop.

In addition, I memoried that yesterday I put my school bag on the floor in the library, about 80cm height. Perhaps it is the reason why the sapphire cap and glass body were broken.

 

Quality acrylic now is still the best choice for making affordable demonstrator pen.