Back before safety razors and during world war II, when steel was scarce, people would resharpen their double edge razor blades on a sheet of glass. I figured why not try it on my Norelco shaver that was leaving my face raw, and it worked, Here is how I did it...
You will need a small brush to clean shaver and heads, also a flat piece of glass ( a mirror or picture frame glass will do).
Step 3: Clean housing and cutters
Step 4: Seperate cutter from shield screen
Step 5: Sharpen blades on glass
Continue the figure eight motion 50 to 100 times and towards the end be more gentle with the pressure. Always keep the glass wet. I tried water but the spit works best, it has a lubricating quality.
Step 6: Replace cutter
Do not remove all the cutters at once as I don't think it is a good idea to mix them up.
Reassemble everything and enjoy a great and painfree shave.