I recently bought a second generation Doric oversize with gorgeous No 9 nib.
When I disassembled the pen for cleaning, I was disappointed to find that the slider was broken and that the little tabs which kept the slider in place was missing:
I decided to sen it to a nibmeister I know in Spain but he told me that it was impossible to repair, I then tried to send it to very famous nibmeisters in the USA but it was the same answer...
So I decided to repair it myself.
The first thing I did was to weld little pieces of 900 silver just on the little prongs that hold the nib in place, but the repair was not solid enough and broke.
Then I tried this technique which worked for me resulting in a working slider which does not breaks (after a month of use): here is the result:
The first step was to "re-create" the little prongs that hold the nib in place. I decided to laminate a silver coin in 900/1000 silver to a thin sheet: here are the steps, I used the gas torch to soften the silver to roll it to a thin sheet:
I then cut the sheet with office scissors to a little rectangle and then to a thin stripe:
I then cut this strip again with office scissors in 4 and checked if they fitted into the original little tabs which were underside the nib which secures the slider in place (seen at the right in the pic):
The second step was to prepare those strips to be welded to the original slider. For that I decided to glue the tabs to a piece of fire brick. This piece of firebrick should be of the same width of the gap between the two slits of the nib:
To cut the brick I smashed it with a hammer first:
Then I used a rock file (tungsten carbide file) to shape it:
Here is the result:
Then I temporary glued the 4 little strips I made in the first step to the piece of shaped brick, the distance between the strips must be the same between the prongs of the slider:
To allow the strips to stay in place when using heat (when welding) I put some plaster around the base of the piece of fire brick using a cut "bottle cap":
When the plaster was dry I removed the plastic cap:
I the left this rest for 5 days to let the plaster completely dry.
The Third step was to prepare the slider to be welded to the little strips: I filed it down with a narrow file to create a shallow depression of the thickness of the strips:
I then checked if those "depressions" fitted the gap between the 4 stripes I glued to the piece of firebrick:
The Fourth step was to hold my breath and prepare myself to welding with a little gaz torch arghhh !!:
I put some solder flux on the place where the slider touches the strips (not too much and not underside the slider):
I then put on the droplets of solder flux some extra thin tabs of brazing material:
I used the little gaz torch to weld everything... and here is the result!:
I cleaned the oxidyzation with steel wool.
The Fith step was to recreate the missing little tab that secured the slider under the nib: I used the same laminated sliver sheet I already used for the strips that I cut with office scissors. To create the holes in this little piece of metal it was impossible to drill because the drill bit were too thick. I used a chisel narrowed to the width of the strips to create the holes:
I then filed down the piece of metal to the size of the original tab and created nicer holes with a thin jeweler saw:
The final step was to get everything together:
I cut the excess of length of the strips and adjusted them to fit into the slits of the nib, and I folded the freshly made prongs underside the freshly made tabs and here we go!!!
Be careful you can fold the metal only once or twice, when you try to do more it breaks!!!
Thank you, hope this will help doric lovers!