Hmmmm, lissthps, special 'sessions', checkin out the slims.... Now I see why where them thar boyz comes from is called the 'deep south'!!
No definite answer for when to change blades. THe easy answer is when you feel them start to pull. Sometimes i can get 3 days on a blade.. other times just 1 shave...
Yeah...I have to agree with that. It certainly depends on the type of blades for me but even then it varies. I usually like to think I get a good 3-4 shaves out of an Astra Superior. But, sometimes they seem to pull on the second shave and don't cut it. Other times, they seem to be too sharp on the 1st shave,then just perfect for like 4 more. Who knows? Derbys, I rarely get a decent second shave out of them. But, in an adjustable like a Slim or Fatboy, for me they are great - if only for the one shot though. I usually try to get a second shave out of em, but rarely have I finished up without replacing it. (But I need the Derby's for the adjustables. If I put an Astra in a Slim, I can count on multiple nicks - period. But with a Derby I actually can enjoy the shave. They are a little duller, or 'softer', than the Astras and fit the razor well with my face.) For me I know when a blade isn't working right anymore when there is simply too much stubble left after a pass. You can tell when it is cutting right. Then, when you notice you have to make more passes, or it doesn't slice off enough the first time round, I just pull it out, toss it, and pop in a new one - mid shave. I have no qualms about tossing one out even if it is 'in my head'. What the heck? If it isn't feeling right, it probably isn't. No sense shaving with a dull bloody blade - suxxxx. (Also, when a blade is getting dull, the shaving lather tends to get little fatty globs showing up on my face after I pass over with the razor, rather than being cleanly swiped of my skin.) So, no science to it that is for sure! Just getting used to what a blade will do for you and then recognizing when it isn't. Carry on Padawan!
I've been changing blades as soon as i feel some uncomfortable pulling and I know I have a good lather going. Generally, I think as you shave you'll start pick'n out the .. ok this isn't feeling right point. Good luck and heck remember the blades are cheap so change often.
Blades are cheap enough not to be really frugal with - I remember using Fusion blades and I'd really stretch those bad boys
I usually just grab a new one every monday. But if I feel like stretching them, I can get 4 or 5 shaves out of a derby without any problem, and 5 or 6 out of a Shark no problem.
Like others a little experience goes a long way. I get the longest usage out of feathers followed by derby's, then Wilkinson. YMMV
You can "feel" that they are dull painful to shave with not geting smooth shaves at all, for me it's razor burn on the neck
My chin is the number one indicator for me. If I find myself thinking about doing any kind of blade buffing there, I know my blade is ready for the big sharpener in the sky...