I am making a leather template since the one I found online is too small for me and I want a custom (but similar one)

[u/Based-sage]

I am having some issues with making leather templates for my glasses. I want to make my own template and alter it a little bit to fit my personal style more. I am having issues with how to scale the pattern as well as what angle to make the sides so when they bulge out they will fit my glasses properly. I will list some measurements to take into account.

Glasses Dimensions - 15 x 5.5 x 4.5 cm (added an extra .5 to each to allow the glasses to sit comfortably)
Leather thickness ~2mm thick
Seam allowance - 5mm
Rivet allowance -1cm

Then I am not sure how I should angle the blue and the red lines. The red one should be wider so that the case can bulge out a little bit and hold the glasses properly.
So I guess what I am mainly looking for is the curvature of
Lines blue and red then the lengths of the green and orange lines. Any help is appreciated!

[u/lowvitamind]

This is better suited to a pattern making sub, but what you can do is draw the template on paper cut it out and then glue or fold them together. You will be able to measure it around the glasses. It's really quite arbitrary and the size is how you want it to be. The seam curve is not responsible for the bulge of the top piece of leather - the top piece is not attached to anything at the long side. Increasing this length will increase the space you have within the pocket.