A push cut?

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How do you define a push cut? I have been conversing with a person and it ends up we call a push cut two different things. His push cut was starting the cut at or near the tip and then pushing the knife forward. In my opinion that is still really a slice. I think of a push cut better I’d say as a press cut. A true push cut is pressed straight with no slicing action at all. However, in reality I do agree a push cut does have a small amount of slice to it but very little. Heck even shaving the blade is angled a little producing a small amount of slice. Is it even possible to cut with a pure pres cut?
 
When I test an edge for sharpness, I push the blade straight into the paper of a newspaper at a 90 degree angle. I use no slicing motion at all. I try to get the blade to push the paper apart.

Slicing paper is easy, but pushing a blade through it requires a significantly sharper edge.
 
Slicing paper is easy, but pushing a blade through it requires a significantly sharper edge.

Yes, a lot of people think this isn't possible or don't do a pure push cut. Simple buy a double sided razor blade and try it iwth that to see how sharp a piece of steel can be. It will go right into paper with almost no force, with no draw and all angles at 90 degrees.

-Cliff
 
A push cut is a push cut - no draw whatsoever. *Can* be done. Do it all the time in the shop to make sure the knife I just finished is sharp.

A good real-world application of the push cut is woodcarving.
 
Most precision craft work is push cut because the knives are very small and if you draw the blade then you quickly run out of blade.

-Cliff
 
After reading this post and believing that it can't be done, I hit the stones to give it a try. I re-profiled my CS Voyager to some angle. I just eye balled it to tell the truth. I was well please with my effort as this was one of my first times trying free hand on a diamond stone. Heck, my grind lines were straight and true even! I then went to my Sharpmaker and went for the 30 deg side. I then stropped for just a bit and to my amazement, I could push cut!!! I never thought this was possible, yet alone by me!
I'm a believer now....but it wasn't newspaper it was just regular computer paper. I guess it probably needs to be sharper for it to be newspaper, but I can see the light at least.

I believe now :-)
 
At first I could just do it about 2 inches from the hold point. I have since been able to improve that and push cut printer paper out to about six inches from the hold point.
 
A push cut is a push cut - no draw whatsoever. *Can* be done. Do it all the time in the shop to make sure the knife I just finished is sharp.

A good real-world application of the push cut is woodcarving.

That is a great example of a push/press cut.
 
One thing to be aware of is that is it very easy to cheat by tilting the knife just a little. To keep yourself honest try giving your knife to a friend, or better yet give him two and let him tell you which one does better on the paper. Don't tell him of course which one was sharper for you.

-Cliff
 
It is also difficult to prevent the paper from flexing slightly witch can produce a small amount of slice. That is why I think it isn't a very good way to test sharpness, but it is a simple and easy way to check the edge, witch for most is good enough.
 
why not take the knife and clamp it upside-down in a vise or something on a workbench, and then pull the paper through it then? the knife wont move and the paper will do its job
 
Do you get somebody to hold the paper taut?

Seems this would take 3 hands to do.


No, the floppyness is what makes it so difficult to cut far away from the point of hold. That is why cutting far from the point of hold is so impressive, as the paper has more give and requires more sharpness to initiate and continue the push cut than cutting right next to the point of hold.

Mike
 
Dan, What did you use to record/encode those videos. For some strange reason vlc player opens up multiple video screens and plays them all simultaneously. MplayerC works fine though....Odd..
 
these play best in windows media player. I encoded them a while back using some "free software"....:D
 
does everyone move the blade that fast? I have a hell of a time getting past 2" when putting the blade against the paper and literally pushing. I got a very clean cut at close to 6" with that chopping like action, starting the motion about 3" above the paper (zdp caly).
 
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