AndyK 

Nail polish with sand! Interesting. The seatpost clamp is supposed to be a press fit, the tighter you make it, the more the post end gets wedged into the clamp - but because the surfaces are so smooth, there is not enough grip. A very pretty design that doesn't have the physics to back it up! Maybe some clear nail polish mixed with sand. I really don't care about messing up the inside finish, you never see it. And if the seat post still slips, I'll toss it on ebay for someone else to try their luck.

coloneluw

Kind of a side question, but I have a Rolls on a C-Record post. I am thinking of upgrading to a new saddle. Not sure exactly what I want yet but lets use your saddles as my starting reference. My question is how much 'height' adjustment did you have to do from a modern saddle to a vintage saddle? Are the rails on a modern/slim saddle tighter to the leather? Reason I'm asking is because I am about at my max height with the Rolls.

AndyK 

Good question. The Rolls is much taller than most modern saddles. Going from my Rolls, to a Specialized Alias, I have to lower the post about 2cm, give or take. So, if you go modern, you will need a new post with more room.