Im going to do a post just like you but for the Derby stick. I bet I can beat 6 months with the Derby stick since its harder than Arko it probably will last longer. Im really excited that you are doing this experiment with the Palmolive. It would be cool if we can find someone to run same experiment with La Toja or Spieck stick But my money is on Derby stick being the King of Longevity, we shall see
Basic formula on Arko was around 0.46 grams consumed per shave. I quit when the stick became to small to hold. Had I loaded that in a bowl, 170 was likely attainable. I consumed 72.3g of the 75g stick for 158 shaves. The nub was converted to hand and face soap for the next week. Just some data so you can make an identical unit comparison if you like.
Just curious on how this experiment is going or went if you are done. I admire your commitment to using just 1 soap until its all used up. I've been trying to use up the last of my bay rum and have been using it for about 3/4ths of my shaves. Been doing this for the last 3 weeks now. While I'm getting great shaves with it. I miss using a rotation of soaps.
Everybody should try using a single soap or cream from start to finish at least once. When I did it and realized how long the soap I had would last, it helped break me of my excessive soap purchases. Years later and I am still working through it all.
I'll have to hop back in with a few Palmolive shaves after the Jeeves Bay Rum is finished. I'll be around shave 9 or 10 when I come back.
