You aren't actually sharpening the blades, just honing them. This is essentially the same process you perform on a honing steel for your kitchen knives. The leather is used instead of a steel due to how thin the blades of your razor are. If you don't have a strop you could also use an old pair of jeans. Either way I wouldn't use your arm as if something did go wrong with the cartridge you could end up with severe cuts. I've had plenty of those cheap cartridges gillette mounts their blades in break and expose their innards.
By using a strop I typically get a cartridge to last for a couple of months before I toss it. They could probably last longer, but that's enough for me. I buy blades maybe once every couple of years due to a combination of stropping and growing a full beard each winter.
I've also tried moving to a safety razor but I dislike shaving enough that I'm not willing to spend that much time on the process each morning so stropping the modern blades is a happy middle ground of savings and convenience.
You aren't actually sharpening the blades, just honing them. This is essentially the same process you perform on a honing steel for your kitchen knives. The leather is used instead of a steel due to how thin the blades of your razor are. If you don't have a strop you could also use an old pair of jeans. Either way I wouldn't use your arm as if something did go wrong with the cartridge you could end up with severe cuts. I've had plenty of those cheap cartridges gillette mounts their blades in break and expose their innards.
By using a strop I typically get a cartridge to last for a couple of months before I toss it. They could probably last longer, but that's enough for me. I buy blades maybe once every couple of years due to a combination of stropping and growing a full beard each winter.
I've also tried moving to a safety razor but I dislike shaving enough that I'm not willing to spend that much time on the process each morning so stropping the modern blades is a happy middle ground of savings and convenience.