slicing 100 ft. of cardboard?

R

rlinger

Joined
Mar 29, 2002
Messages
4,591
I have all of my first knife complete except final shaping of the scales and guard. Being my first and inexperienced not sure how the edge would hold up. So I put an edge on it that would shave and then cut 100 ft. of cardboard. The cardboard was that of a large shipping container (whatever gage that is). After 100 ft. it still shaved and I am not sure I could tell if there was much wear on the edge, however there has to be some.

I don't know if this test proves anything or not except that it didn't dull the edge. Is this type of 'edge retention' test okay for gaining a general idea of the blade's edge retention??? I've read something about a 'brass rod' test but know nothing about that.

The steel is O-1 tempered at 375 F. then refridgerated at 0 F. overnight then tempered again at 350 F.

Roger
 
Cardboard is a very good test for edge retention as it is very ruff on a edge.100 feet is good,Most people keep going until the knife is dull and see how much it will cut before loosing its edge.If you really want to do the test right pit two pieces of tape on the blade with a space between them and only cut with this section of the blade,That really lets you know as you arent using one part then another ,if you know what i mean..
Sounds like you are doing good with the first one,Now lets see some pictures of it finished..
Bruce
 
Roger, seems like 100 ft of cardboard is great. That should get anyone through a hunting season, anyway.

Dave
 
Thanks. I'll try the test again with a fresh edge and keep going til it no longer shaves.

Bruce, as you suggested, I just posted a pic. on this Shop Talk forum of the finished knife (actually its a link to the picture).

Thanks to all of you for the help I have received in my efforts to learn some of this stuff.

Roger
 
Okay, here's what I came up with:

I put a fresh edge on the blade and began the test a new starting at a count of zero ft. of cardboard. In sharpening, I went as far as the fine grit stone. For the first test I only went as far as medium grit.

At 177 ft. of cardboard it still shaved and probably close to as effortlessly as it did before cutting any cardboard (but who knows and its my blade anyhow but it shaved effortlessly). I cut another 26 ft. and tested again. At that point (203 ft.) it would only shave if forced to and did not even grab at it very well when lightly pressed. Somewhere between 177 and 203 ft she dulled.

According to my digital caliper the cardboard appears to be about 5/32 inch thick (reads about .166 inch).

I don't know. What do the experts think?? I have no benchmark to go by except that I think I'm pleased.

Roger
 
Sounds like you got it like it hould be..The only other thing you can do is sharpen it and see if it will chop wood without chipping the edge.If that works then I would say your right on the money with your heat treat..
Bruce
 
Okay. I'll try to try that. I am going to be at the camp tomorrow evening. If I have time to resharpen and do that test before Thursday I will. My dad arrives Thursday evening and I am planning on giving my very first knife to him that evening for his early father's day. I will take my 10X loop with me to check the edge after chopping wood. If it chips it ain't no good anyhow.

Roger
 
Just because it chips doesn't mean it isn't any good.Just a slicer not a chopper.If you have a real thin hollow ground edge it will more than likely chip,A flat ground edge with a Moran (convex) edge is more suited to chopping....Don't give up on it if it doesn't hold to the chopping.Allot of knives are not set up to hold up to chopping but only slicing and skinning.
Bruce
 
Its a flat ground. Maybe I better just lay off this one. Its designed to be a field dresser and meat cutter anyhow (a drop point).

Thanks.

Roger
 
Roger
I make many knives for meat or skinning only
with very thin hollow grinds and this is what
I made them for,if used as a pry-bar there will be
problems, I make machetes too but with different steel
and a different grind and temper.
I think you need a different tool for a
different job,in many cases.
bowies are great for all around jobs but to do a ring job
on a deer I'd rather have a smaller blade the bowie will do the job
BUT,,,
anyway as long as it does what you what it to do
and it does It well that's great.
  the only thing I can add is,, if it sharpens fairly easy
your in the ball park. (the refrigerated at 0)won't help you
on O1,
but your effort is there. tempered at 375 your Rockwell is
going to be high, so I wouldn't do to much chopping with it
but it will work for a good meat cutter for you though I would have
tempered at a littler higher temp.
to bring that rockwell down some.
did you differential temper it? only my point of view here.
very nice looking knife your doing great..
 
Yea, I tried to hit around Rc 62. That's why the 375 temper. It does seem to sharpen rather easy too. I made it as a field dresser - the drop point.

But, wouldn't a refridgerate at -100 F. help the O1 (if I can get some dry ice)?

Roger
 
From what I know about it, O1 was not made to be
cryogenically enhanced and does not
have in it what can be helped
by a sub zero quench.
the argued point would be
if it is helped ( I'm talking at -300 deg )
the benefit you may or may not get isn't worth the
bother.. Most your knife S/S's are made to be cryo'ed
therefore do benefit 30+%, some say -90 deg. will help
but not as good as -300
but o temp won't hurt it that's a sure thing.
  there are many things said on this subject.,..

 just my opinion of what I know here guys, don't shoot me.
  I got wacked the last time on this subject
 so I'm not getting into it to deep.
 
You must log in or register to reply here.
Back
Top