title says it all...
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.
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.Quote:
Originally Posted by Gawker
And the spine will wear down as well.Quote:
Originally Posted by Blade Wielder
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.Quote:
Originally Posted by Joe Lerch
X
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.Quote:
Originally Posted by Joe Lerch
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
Is there a chance of purchasing a translated copy of that book Nenad?Quote:
Originally Posted by superfly
THis can't be right, as can easily be demonstrated with different 5/8, one with a thick spine and one with a thin one.Quote:
Originally Posted by superfly
A while back we had a thread where I demonstrated how to determine the bevel angle of a razor. It's typically about 11 degrees. Using that value, the ratio of the blade width to the spine would be a around 4:1. However you will find that this angle varies with the blade design, as does the thickness of the spine for a a particular width blade.
From the descriptio it's clear that this is only a particular shape of blade. Only one shape (full hollow?) has that belly.Quote:
Originally Posted by superfly
Tony Miller gave you some examples, and I invite you to compare the spine thickness of a Begischer Lowe with one of the Dovos in the low price range that has the same blade width.
Joe,
I notice it also in the various Dovo models. The tortoise shell one I sell has quite a heavy spine as oppsoed to the basic one in my kits yet both are 5/8.
My Thiers- Issard frame back has a 1/4" thick spine and it is a 6/8.
Tony
The 3.5 to 1 ratio is mentioned in that text on the razorcentral website
http://www.en.nassrasur.com/razorcentral/index.html
but it is not a hard and fast rule as Joe Lerch has shown.
Quote:
Originally Posted by randydance062449
Thanks Randy, I think I'm going to take a while and peruse that site. Info like that is very much appreciated! :D
If you look at the different grinds at that site you'll notice that only the full hollow has a belly.Quote:
Originally Posted by randydance062449
Larry, I have no idea, but i think it is unavailable :(. I found that info on nassrasur website, maybe someone there has a copy of that book? The guy's name that runs that place is Arthur E. Boon.Quote:
Originally Posted by Korndog
http://www.en.nassrasur.com/razorcentral/index.html
ref:
Reichszinnungsverband des Buchsenmacher- und Messerschmiedehandwerks. Das Rasiermesser, sein Werdegang, seine Pflege. Verlag der Messerschmiede, 1939. Out of print.
I'm not sure as to how accessable Mr. Boon would be but Razor Central once had it's own site and then disappeared for a while and now it's being hosted by NassRasur.Quote:
Originally Posted by superfly
NassRasur, is owned and operated by Norbert Schick (he's the guy in the DOVO video) and Norber also specialises in seeking out rare and out of print books :D Soooo..... one would only need to contact Norbert to see if there is any chance of getting a copy of "Das Rasiermesser" because if anyone know's I'd bet he does. If you havent looked around NassRasur, you should. He has a great collection of info there including some neat books for sale. Alas, no mention of a copy of Das Rasiermesser :(