How a Razor's Gap Dimension Can be Useful

I am on record as saying that the blade-bar (or blade-guard) gap as defined in a recent article (click here) is of little value in understanding the shaving character of a razor. I still assert this is true. The good news about the gap is that it's relatively easily measured using a feeler gauge.

This image is from the following web page:
http://wiki.badgerandblade.com/Image:SHAVE_ANGLE4_jpg

Okay, easily measured, little value: so who cares?

Well, I've thought of a way to put that information to good use. The razor's gap dimension -- something that can be measured with some degree of accuracy -- can actually be used to determine the dimensions of the important aspects of razor design, which have been previously unobtainable to any reasonable degree of accuracy. These aspects are blade exposure and span.

The key is to begin with a good side-view close-up photo of a given razor head with the blade installed and with the camera lens pointed directly down the blade edge. Although measurements can then be taken directly off a computer monitor, it is probably best to print a hard copy of this side view.

Then with a pair of dividers and a high-quality ruler, measurements of the gap, span, and exposure are made.

Once those relative measurements are made, they can then be converted to absolute measurements using an adjustment factor derived by comparing the known actual gap dimension to the gap measurement as taken from the side-view enlargement.

So kudos to those behind the razor blade-guard-gap database, which can serve as the foundation step and can potentially, eventually be converted to a matrix of dimensions on DE razors' big three characteristics: span, exposure, and angle. If that ever becomes a reality, we will all then have a better handle on the shaving characteristics of various razors and how they compare to each other.

Happy shaving (and measuring and comparing)!