Thanks to guys at /r/fountainpens I got an idea for the gift to my father. I got him a new pen and made accompanying notepad and pen sleeve.
For the outside I used Hermès Clemence leather. Lining leather is Barénia.
Hand sewn using a saddle stitch with linen thread Lin câblé N°532 and 632.
After browsing /r/fountainpens I chose Leuchtturm notepad and Caran D'Ache pen with some spare ink. Thanks again guys, he is retired engineer and he did a lot of technical drawing, I hope he will like it.
First part of the construction were side holders for the pen. I skived the leather to 1/4 of the thickness so clip of the pen can slide through.
Then I lined it with vegetable tanned white lamb leather, because it will be in contact with the metal of the pen (I heard different opinions that chrome tanned leather may or may not causes rust, I wanted to be sure).
Cut to the desired dimensions with skived ends.
I decided to use two holders because the pen is bit heavy and long, so it will get enough support.
Because of the skiving it wont bulge at the joint.
Edge painting, treating with heat, sanding and applying wax for protection.
Cutting out the main panels.
Gluing front and lining leather around the edge before stitching. Recently I got fond of Renia Aquilim glue, which is water based, odor free and still quite strong. Highly recommended.
Cutting ovals to the side panels, so the notepad can easily slide in and out. Curved blade helps a lot.
Creasing edges with the heated fileteuse tool.
Stitching pen holders to the side panel, so the back stitches wont show at the back of the notepad.
Hammering stitches so they lay flat and uniform. For some reason I really enjoy this part.
Gluing side panels to the main construction.
Building the strap, which will be used for the closure.
Since Barénia is stiffer leather, I rather cut out the shape from it then from the flexible Clemence.
Afterwards excess leather is cut off.
Applying multiple layers of the edge color. For the strap I went with the darker blue that match the color of Clemence leather on the front.
Stitching simple piece for the closure of the strap.
Testing the symmetry and placement.
Coloring the edge of the notepad with lighter blue, that will match the Leuchtturm notepad I got for the inside. Multiple layers, heat treated, sanded and waxed.
Testing the fit of the notepad. I really like the Leuchtturm, it has nice paper and numbered pages, I will get one for myself. Tip is from /r/fountainpens.
Marking stitching holes with the pricking iron at my favorite 8 SPI.
Stitching the construction together around the edge.
Double stitches along the closure strap.
At the spine of the notepad I installed small mini-handle from stiffer Epsom leather. Lined with the white lamb.
One can slide hand through the mini-handle or hold it as if it was a mini briefcase.
For the pen I made very simple sleeve from the matching leather.
Gluing and shaping with the bone folder.
Creasing the closure strap.
Edge painting and stitching.
Thank you for looking to the end.
If anyone is interested, here's growing archive of my other experiments with leather: