You have the right idea -- change the blade when it’s noticeably duller. But I’m surprised that you get that much life out of a blade. I change my Astras after about six or seven shaves. What kind of blade do you use?
I'm new to wet shaving myself, and the rule I'm using is that when it starts to cut, pull, or generally not run smoothly, it's time to change it. Might not be the 100% correct way, but as cheap as the blades are, I don't feel too badly about changing them out frequently.
I change mine once a week. I can go up to two if I flip the blade over.
I generally will go a week on each side of the blade. I use Astra Platinums.
I get four or five shaves from each blade.
I use my Astra blades only twice. After I've used one, I dry it and wrap it back up in its coverings, with the outside wrapper turned inside out so I know I've used it once (I only shave with a DE about once a week, normally I shave with a straight...)...
I've never had a problem getting a week out of my blades. I never tried going for a longer stint - just what my grampa told me to do. I'm going to try David F.'s idea of fliping the blade over to get an extra week. I use Wilkinson's blades
Right on, Abner. I also use the Wilkinson Sword. Each side goes 6-7 days for me.
By the way, the Wilkinson Sword company has an interesting history. According to their Wikipedia page, they got started making firearms, bayonets, and swords in the 1700s.
Probably best to change the blade when it gets dull.
I've gotten 17 shaves out of the current Astra Blade that is in my DE. I know that I probably won't get that out of every one of the blades, but when trying a new blade I like to see just how far they can be pushed. I got close to 17 out of my last Crystal blade, it was 14 I think to be exact. I'm going to change the Astra this weekend simply because my razor needs to be cleaned after all those shaves, but that thing is still sharp as hell.
Its going to vary with the brand of blade and the thickness/coarseness of your beard is essentially what I'm trying to say. I happen to have a fine beard that is not very thick at all, think my native american heritage for that little gift, so I get a lot more shaves out of a blade then someone with a thick course beard that has to shave everyday, I only shave ever other day.