Edge thickness

  • Thread starter Thread starter AF
  • Start date Start date

AF

Joined
Jan 14, 2000
Messages
6,015
I picked up a Livesay RTAK recently. I love the knife. My next biggest knife, a Fallkniven A1, now appears small. In particular, I think the handle and sheath are very well designed.
The one thing that has frustrated me is the thick edge. I want to knock down the shoulders and reprofile the actual edge.
How much can I take it down before the edge will lose much of its durability?
 
Every edge is a compromise between durability and cutting ability. Only YOU know, what the the purpose of your knife might be....
The people at Fallkniven probably did some thinking, too (and stay on the safe side).
Happy sharpening
smile.gif



------------------
D.T. UTZINGER
 
As usual, Herr Utzinger is absolutely correct. One thing that would help us advise you more knowledgeably is if you would put a dial caliper on the edge of the knife and tell us what the thickness is. Walt
 
AF: Do testong on your own. If you chop wood with it, don't take it too thin at all!!!! If it chops light brush sharpen away. I sharpened my benchmade folder until the very tip started to chip out (it was veeeery tiny, but noticeable.) From there I backed up the sharpening angle a bit. Do the same with the RTAK.

P.S., do you have a belt sander?

------------------
"Come What May..."
 
...chuckling... Belt sander, you might need it...I had to spend a couple hours with diamonds to get what "I" wanted (much smaller blade though).

1095 is fairly tough. But as Messers Utzinger and Crayola have said, your usage will be the key. On that size knife, err on the side of caution.

(That being said, I talked to Newt today and placed another order...
smile.gif
)


Steve-O

[This message has been edited by Steve-O (edited 01-08-2001).]
 
Your edge will loose a very small amount of durability for every degree of edge profile you drop, and gain about the same amount of "true" sharpness.

I have a Battle Mistress that I have not dropped at all and last friday I chipped the blade out in three places rather significantly. I could be wrong but I think Cliff mentioned that the edge is around 30-33 degrees.

Now, I was using the blade full force to chop down two eight foot tall lemon trees. For nearly four hours the knife did not chip while delimbing both trees to stumps.

The only reason it did chip out was that I used it to chop the roots out and struck plenty of rocks full force.

I think that your knife is, just by guessing, thinner at the edge than the Battle Mistress. So as the above have all mentioned it's all in the use. If all your going to do is chop wood you could probably thin the edge out some.

The good thing is, is that if you thin it out too much you can always use a steeper angle next time you sharpen until the edge is strong enough for the use that you put it through.

Later, Jeff
 
Thanks for the input, folks.
At the very least, I think I should be able to round down the shoulders. This should improve cutting ability without changing the edge angle- so the edge would not be weakened.
I'd like to hear from Talmadge(I think he has an RTAK) or another RTAK owner who obsesses about edges. I don't know the exact angle the RTAK is ground.

-Andrew
 
I don't have an RTAK, but I've heard a few things about RTAK edges. First, they appear to vary from batch to batch, and even knife to knife. Second, there is ample evidence that some of the RTAKs come out with a really really thick edge. It wouldn't surprise me at all if you have room to shave the edge down a few degrees, or even more than a few degrees. I'd go out and buy the hardest wood I could find, chop it hard, and if your edge holds up, starting shaving it down a few degrees at a time. Sorry I can't give any more exact advice, but that's the process I'd follow.

Joe
 
Thanks Joe-
I don't know why I thought you had an RTAK. I think maybe in an archived post you said that you planned to buy one? It doesn't matter. I'll do some testing myself, as you suggest.

-Andrew
 
You may find that by simply knocking the shoulder off the bevel you will increase the cutting efficiency a lot. That basiclly creates a convex edge which I find works pretty well. Use about a 12-15 degree angle and round over the top of the current bevel as much as you like, down to about half of the present bevel width. You'll be amazed at the difference it makes.

------------------
Jerry Hossom
www.hossom.com
The New Tom & Jerry Show
 
AF:

<font face="Verdana, Arial" size="2">How much can I take it down before the edge will lose much of its durability?</font>

The edge loses durability as soon as you start to remove metal and continues at a constant pace. How thin you can grind the edge depends on the material you are cutting and the method being used to cut it.

The safest way is probably as Joe describes. Thin the edge a little each time and when it starts taking some damage then put an additional bevel across the very edge at a slightly more obtuse angle (just a few degrees).

A note of concern, if you really grind away heavily, and say drop the blade 10 degrees in one shot, you might find that when you hit a knot chopping wood you put a dent in the blade nearly the size of the bevel which will take quite some effort to fix.

It will take some work, say 5-10 sessions. But if you go slow and lower the bevel only 1-3 degrees per session, you will eventually end up with an edge optomized for you without risking excessive harm to the blade.

-Cliff
 
<font face="Verdana, Arial" size="2">Originally posted by GaKnife:
You may find that by simply knocking the shoulder off the bevel you will increase the cutting efficiency a lot. That basiclly creates a convex edge which I find works pretty well. Use about a 12-15 degree angle and round over the top of the current bevel as much as you like, down to about half of the present bevel width. You'll be amazed at the difference it makes.
</font>

That's a good point. It also makes re-sharpening easier, when you have a thinned-out bevel above the edge itself. In fact, I do this ( I call it double-grinding) on a lot of my knives.
 
Back
Top