Montegrappa "miya" - Repair Stripped Cap Threads

May 16, 2018

Hi all,

I’ve just repaired a Montegrappa “Miya” on which the cap threads were completely stripped.

The cap/barrel threads engagement being only 2.5mm, and the acrylic being very soft, the female threads are prone for stripping.

I really c’ant understand why Montegrappa made such a beautiful pen while neglecting this potential risk.

Below a picture showing the repair.

I’ve made and installed a hard “Peek” threaded ring inside the cap.

The ring is installed in a radial groove I’ve turned inside the cap and is glued in the groove.

Th outside diameter of the ring being 0,3mm larger as the cap entry in front of the groove , I succeeded in pressing the ring through the narrower diameter with a special tool.

The threaded ring then expanded it its seat groove and was secured with epoxy glue.

The ring being now axially secured in the groove and axially/radially with epoxy glue

This worked perfectly and the big benefit is that the Ketron Peek is very hard and wear resistant.

However the thread engagement remaining very limited I suggested the owner not to over-tighten the cap !

Francis

PS : Excuse me for my dirty fingers on the second picture….

http://i62.photobucket.com/albums/h89/fountainbel/Improvements%20to%20modern%20fountain%20pens/2018-05-162015.52.16-1.jpg

http://i62.photobucket.com/albums/h89/fountainbel/Improvements%20to%20modern%20fountain%20pens/3bdf830a-3d24-46cb-b26a-3457b351aae0.jpg

August 31, 2019

Dear fountianbel, very interesting post. I am always interested in and appreciate seeing solution to a pen problem.

I have two Montegrappa Extra 1930 style pens, one is the classic Extra 1930 model, the other the “La Verde Roma” edition commissioned by Rome pen shops Corsani and Novelli. La Verde Roma has the threads that come to a blunt stop when reaching the end where you expect pen to tighten and stop, all feels correct. The Extra 1930 model has the threads that don’t feel like a hard stop when reaching the end. It feels a gradual tightening where the end point is not clear. It doesn’t turn loose and free turn. If I really try to tighten it, it will stop. I never tighten it too hard, for fear that the cap might crack, or thread spcan be stripped. I don’t know if this is by design. So far it’s not a problem, but I would prefer the “hard stop” where you know where it really ends. Much appreciate your opinion.

Kind regards,

como

Hi all,
I’ve just repaired a Montegrappa “Miya” on which the cap threads were completely stripped.
The cap/barrel threads engagement being only 2.5mm, and the acrylic being very soft, the female threads are prone for stripping.
I really c’ant understand why Montegrappa made such a beautiful pen while neglecting this potential risk.

Below a picture showing the repair.
I’ve made and installed a hard “Peek” threaded ring inside the cap.
The ring is installed in a radial groove I’ve turned inside the cap and is glued in the groove.
Th outside diameter of the ring being 0,3mm larger as the cap entry in front of the groove , I succeeded in pressing the ring through the narrower diameter with a special tool.
The threaded ring then expanded it its seat groove and was secured with epoxy glue.
The ring being now axially secured in the groove and axially/radially with epoxy glue
This worked perfectly and the big benefit is that the Ketron Peek is very hard and wear resistant.
However the thread engagement remaining very limited I suggested the owner not to over-tighten the cap !

Francis
PS : Excuse me for my dirty fingers on the second picture….
http://i62.photobucket.com/albums/h89/fountainbel/Improvements%20to%20modern%20fountain%20pens/2018-05-162015.52.16-1.jpg
http://i62.photobucket.com/albums/h89/fountainbel/Improvements%20to%20modern%20fountain%20pens/3bdf830a-3d24-46cb-b26a-3457b351aae0.jpg