Thread: anybody know the ratio to figure spine thickness compared to blade width?

title says it all...

Ratios? How to figure out spine thickness? Personally, I just grab my tape measure.

Besides, if the blade has been honed a lot, the original size of the razor will have been reduced.

I think the answer you are looking for is 3.5

blade width = 3.5 x spine thickness.

There is a thread a month or so ago that covered the topic more extensively, if you are interested..

I though it was 3.5 but couldn't remember which direction or if that was the correct number thanks guys.

Originally Posted by Gawker

title says it all...

I don't believe there'a fixed ratio between blade width and spine thickness. It varies with razor design. For example you can have a 5/8 with a thin spine or a thick spine.

Originally Posted by Blade Wielder

Besides, if the blade has been honed a lot, the original size of the razor will have been reduced.

And the spine will wear down as well.

Originally Posted by Joe Lerch

I don't believe there'a fixed ratio between blade width and spine thickness. It varies with razor design. For example you can have a 5/8 with a thin spine or a thick spine.

Maybe we should talk about the deapth or heaviness of the spine when we're talking about the kind of thickness you're referring to, Joe.

X

Originally Posted by Joe Lerch

I don't believe there'a fixed ratio between blade width and spine thickness. It varies with razor design. For example you can have a 5/8 with a thin spine or a thick spine.

There is, and it is the 3.5. It is fixed number, and it is used to retain the sharpening angle at the edge of the razor.

Nenad

I have to go with Joe on this one. There are razors with heavier spines and lighter spines in every size, the ratio would be different between them. The older Fromm razors had a fairly thick spine and were 5/8, the newer fancy Fromm's are thinner at the spine but still a 5/8 razor, the ratio has to be different as the 5/8 is constant.

As a generality 3.5 may be an average but not a hard and fast rule.

Tony

This is a section from the German book “Das Rasiermesser” (The razor) has been written in 1939 and was published by Der Messerschmied Verlag. It goes into detail about production techniques, geometry, and it also addresses the increasing competition with safety razors and electric shavers.

"One of those rules is the to conserve the thickness of the back, which should be the blade width divided by 3,5. The hollow grinder divides the blade in two halfes: the upper part is hollow, the lower part is a biconvex belly. The biconvex part consists of the edge, the thinning and the belly. The biconcave part of sole, the hollowing, the back and the stabilizing piece. The sole is the thin transition between the belly and the hollow part."

I guess there are some small tolerances within this rule...

Nenad

<< should >>

And there you have it <g>

Tony