questions about razor spine

Sanch

Active Member
How thin should the spine on a wedge razor be? How thin is too thin to begin with? And finally on a frame back what should the spine thickness be in relation to the frame cross section/diameter ie
1/8"thick blade 3/8" thick frame with blade in center? I hope my questions aren't too vague?
 

rhinoknives

Well-Known Member
I have not made a straight Razor but I do have some information that may help you design yours?

On traditional German & Britsh straight edge Razors, the thickness at the crown of the spine sets the angle when you put the Razor on a stone to sharpen. So that will give you part of the equation & I hope that bit of info was helpful.

I know this from selling Razors & shaving accessories retail for a few years.

Laurence

www.rhinoknives.com
 

ElementFe

Member
I'm in the same position, Sanch.
Just getting ready to try one, though I make lots of other knifey things.
My approach is to just get an average looking razor at a flea market and get out the measuring tools and copy it for starters.
The spines seem to average just under a quarter- since I'm not interested in doing wedges I can't answer that part, have never held and evaluated one.
 

rhinoknives

Well-Known Member
Find some older worn out or rusted American, German or British made ones to get the measurements off of.

I have seen a few new chinese made ones that don't really look like they where made to shave with? More like cheap weapons. lol

Laurence

www.rhinoknives.com
 

cardoso5fr

Well-Known Member
You will find all the answer to your question here
http://straightrazorplace.com/srpwi..._Great_Straight_Info_Razor_Central_Manual.pdf

That is indeed the back thickness and the edge which give the angle on the stone.

That is function of the highness of the straight you do.

For a 8/8 i use between 5.5 and 6.5mm thick steel. For a 5/8 that is between 4.5 and 5.5. There are some rules, but with those thickness that is not bad :D

You make blade highness x 1/4 and you have more or less the right thickness to the back.
 

Drew Riley

Well-Known Member
IIRC, you want somewhere around a 3:1 to a 3.5:1 ratio between your spine and the width of your razor. Equally as important is the thickness (or rather the thinness) of your edge. Some where around .005" is typically a desirable thinness.

You want to made sure that it's thin enough that when you establish your sharpening angle (which as Laurence stated, is relative to width / spine thickness), your bevel doesn't exceed about 1/16th of an inch in width. IOW, if you measure from the point of your edge to where the secondary bevel begins, it shouldn't be wider than .05 to .06 inches or so. Any wider, and you're just increasing the amount of metal that you have to remove when sharpening, which makes things that much more difficult.

Now, you CAN mitigate this (on older razors that have been sharpened a million times, for instance) by raising the spine a little bit and increasing your sharpening angle. This can be accomplished by putting a couple layers of tape on the spine. Obviously this is somewhat of a compromise from a thin sharpening angle, but it makes things a little easier.
 

Sanch

Active Member
I've been"lurking" at SRP it's a great place !!! Have since forged a couple more RSO razor shaped objects thanks for the replies!
 
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