Summary
Customise then print these and stick them on your keyboard. Patterns and spacings on V2.2 from Marburg Medium braille font standard.
~see instructions~

Please provide suggestions for improvements.

Next version to include better dot height functionality.

v2.3 - 23 July 2015
Added Braille Scale Multiplier to increase braille size.

v2.2 - 7th May 2015
Made Customisable

The scad file has a matrix of all the braille letters that you can use in your own project if you wish (to save you from having to make them yourself)
Instructions
For best results open in OpenSCAD, instructions - https://youtu.be/cukWgTyvWNs

CUSTOMIZER_V2.3.scad
Current Thingiverse Customizer version
The most up-to-date version, tweak the settings yourself. Based on braille worldwide medical standards http://www.pharmabraille.com/

Default size is at minimum key size, you will likely want to increase this.

• Use "Text Drop Down Box Select sets" to create stls of specific character sets (all,alphabetic,numeric,symbols,functions,commands) due to the complicated operations thingiverse might have problems rendering the whole set at once.

• The main settings to modify are Base Height, Key Size & Braille Scale.

• If you want to customise this more, all the braille settings regarding spacing and dot height are accessible if you download the scad file and open it directly in OpenSCAD. You can eliminate rendering problems on thingiverse by using OpenSCAD also.

braille_allKeys_v2.2.stl
default settings, $fn=21
All V2.2 keys. Warning these are at the minimum possible size. use customiser to increase to the size of your keyboard keys in mm.

/////////////// OLD STUFF LEFT HERE JUST BECAUSE ////////
OLD WAYS :(
brailleOpenSCAD_v1.zip
Contains the following 3 OpenSCAD files to create higher quality custom tiles (using Braille Normal font). Along with the original Customer version:

customisable_brailleKeys_v1.1.scad
This one uses thingiverse's built in "write/braille.dxf" font which is lower resolution and only supports alphanumeric & symbols.