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kungpao
04-13-2013, 01:00 AM
I'm new to sharpening and looking to finally pass the paper push cut test. I have been working for around 3 months on freehand stone sharpening. I currently have a gesshin 1000 and 5000 grit stone. I seem to be able to pull cut through paper with out a problem after sharpening, but push cuts just aren't happening. My basic technique is to sharpen each side until I feel a burr. After I finish creating burrs on each side, I lightly run my knife in a horizontal swiping motion to remove the burr before moving to the next stone. I then repeat the process and try to strop on an old leather belt after both stones are complete.

Do I need to continue polishing my edge with higher grit stones, or work with a coarser grit stone before the 1000? I feel like I am starting to comprehend what I'm doing but still fall a bit short. Thanks in advance.

Bill Burke
04-13-2013, 01:51 AM
Just keep practicing. if you get the edge right you can push cut paper with a 320 grit edge. A fun thing for you to try is get a piece of college ruled note book paper and cut it into strips two lines wide. take a #11 paper clip and tie a piece of string to it so you can hang it from a doorway at about shoulder height. now put one of the strips of paper in the paper clip so the paper is hanging vertically. take your knife and cut the end off the paper without pulling it out of the paper clip. if you can do this then see how many times you can cut the paper before it gets too short to cut or you pull the paper from the paper clip.

Seth
04-13-2013, 01:52 AM
You might try passing on the old belt; compressing soft leather which pushes the leather up on a trailing stroke could be dulling the edge. 5000 should be providing a good polish to the edge. Maybe just do a cork instead till you get a better strop material.

jgraeff
04-13-2013, 02:00 AM
I'd suspect bevels are not as good as they could be. Try to be as consistent as you can along the whole edge on both sides. Also use cork or wood to deburr then strop and deburr again. You should be able to slice paper effortlessly with a 1k edge. Then go to 5k. But if 1k edge is not good don't move foreword.

franzb69
04-13-2013, 02:13 AM
i'm with jgraeff with this. consistent angles will give you a consistent edge. even a 500 grit edge will push cut paper, albeit roughly but it can do it.

chinacats
04-13-2013, 02:29 AM
Greetings! Practice, practice, practice...

panda
04-13-2013, 04:07 AM
get a piece of crap knife. on your 1k sharpen for 5 minutes on one side, do the other side for 5 mins. flip again and go for 2 mins with less pressure, other side 2 mins. then single stroke push alternating sides each stroke with only the slightest pressure for about 3 minutes. if by this point the knife does not push cut paper, your angles are not consistent enough (and/or not sharpening all the way to the edge). just repeat the whole process over until you get it right, hence using a piece of crap knife you wont care if you wear the hell out of.

Lefty
04-13-2013, 08:32 AM
Keep at it, and buy a Sharpee and a loupe.

Benuser
04-13-2013, 06:46 PM
All excellent advices, I will just add one more. For push cutting the thickness immediately behind the very edge is essential. Sharpen a relief bevel on both sides, at the lowest angle you're comfortable with, until you almost reach the very edge. Verify the scratch pattern with a loupe. If you don't have one, perhaps you do have a SLR standard lens. Then sharpen as you're used to.
Would you have a micrometer: reasonable values for the thickness at 5mm behind the edge are .5-1mm.

kungpao
04-14-2013, 07:13 PM
Thanks for all of the advice. I had a feeling my angle consistency was the culprit. Are there any basic tips to help with keeping my angle straight without using the clip on guides? I'd rather be 100% freehand from the get go.

panda
04-14-2013, 07:27 PM
practice. took me a year before i felt like i actually got it right the first pass.

SpikeC
04-14-2013, 07:29 PM
Practice! And watching really closely at what you are doing. If you go slowly at first and watch how the angle changes as your stoke moves back and forth you can start to build some muscle memory, your arms have to shift a bit as you go back and forth. Try to keep your wrists steady and move from your hips instead of your arms.

Zwiefel
04-14-2013, 09:04 PM
I'm sure that someone will make fun of me for this (and that's ok :doublethumbsup: ) ....but I have watched closely and found that having a wide stance helps (a little wider than shoulder width), with one foot ahead of the other. I'm a lefty so I put my right foot first...helps to keep my body out of the way of my elbow.

SpikeC
04-14-2013, 09:27 PM
Nothing odd about that! A stable base is very important when you want repeatable results!

jazzybadger
04-15-2013, 01:09 AM
I'm sure that someone will make fun of me for this (and that's ok :doublethumbsup: ) ....but I have watched closely and found that having a wide stance helps (a little wider than shoulder width), with one foot ahead of the other. I'm a lefty so I put my right foot first...helps to keep my body out of the way of my elbow.

Hell that's what I do even when I'm just cutting food. Absolutely in agreement with Spike; a solid stance is nothing to mock.

ThEoRy
04-15-2013, 01:44 AM
You may be rounding the edge on that belt. Try a proper felt or leather stropping base loaded with diamond ftw.

kungpao
04-15-2013, 11:29 AM
I've posted in many forums but this one has to be the most efficient and helpful one I've had the pleasure of dealing with.:thumbsup:

Dusty
04-15-2013, 11:59 AM
The best tip that I've gotten for beginning sharpening, was to avoid using too much pressure on the stone. If you're pressing down, then the drag of the knife will drag your angle up and down as you sharpen, build up muscle memory sharpening very lightly.

stevenStefano
04-15-2013, 12:59 PM
I think if you start off with a pretty high angle it should be much easier to get it consistent when you're starting off

jgraeff
04-15-2013, 02:00 PM
The best tip that I've gotten for beginning sharpening, was to avoid using too much pressure on the stone. If you're pressing down, then the drag of the knife will drag your angle up and down as you sharpen, build up muscle memory sharpening very lightly.


i disagree here i think pressure is misunderstood in sharpening. I have found using a bit of pressure speeds up sharpening, also knowing when to use lighter pressure helps as well. On course stones i will use mild pressure and on finer stones i use more pressure and lighten as i finish it.

just my .02 maybe others will comment as well

Bill13
04-15-2013, 02:45 PM
I am curious about how many people use a loupe? I use a 20X and find it very helpful. I do wonder that if/as I get better it will not be needed.

The Anti-Chrysler
04-16-2013, 01:19 AM
Holding a consistent angle seems to be the hardest part for me, and the longer the blade, the tougher it is. However, I can get my paring knives freakishly scary sharp.
Just keep at it.

xuz
04-16-2013, 01:34 AM
I have 30x loupe that I bought couple decades ago and use it occasionally to check my razors. You use it less and less as you get better.

What paper are you cutting? Newspaper, xerox paper, magazine, cardboard, etc all have different grains and some will cut better than others depending on how you cut it.
What kind of knife are you cutting them with? Some will cut better than others.

Pushing cutting a single sheet of Xerox paper is a bit special because you don't push any material aside. That means you don't have to worry about anything other than your bleeding edge. Things like consistent edge angle or geometry that may make difference in the more practical cutting tasks don't make much difference at all. That means you shouldn't be spending 10 minute trying to thin out your geometry or get even angles. As an example, I can sharpened on 1k stone (in 2 min or less) a very dull ~40 degree Mora camping knife with bad geometry to push cut through a printer paper. Just grind the edge real crisp, without burr or wire, and it should do just fine. As someone mentioned before, use a sharpie.

sachem allison
04-16-2013, 01:57 AM
You don't eat paper, sharpen it until it cuts food the way you want it too. Food and paper are many different things and perform differently. You maybe able to push cut printer paper and still not cut cleanly through an overly ripe tomato. I'm not trying to discourage you. Good technique, consistency and practice are the key to good sharpening. At the end of the day you aren't eating the paper.

Zwiefel
04-16-2013, 01:58 AM
xuz reminded me...pushcutting paper/newsprint/etc is actually a skill. Many times a friend has tried to follow me doing it and failed with the the very same knife. Its not a very difficult skill, but a skill nonetheless.

Not sure how that affects the OP.

Justin0505
04-16-2013, 07:04 PM
A few tips in addition to those already mentioned that helped me:
- one hand controls the angle and the other the motion; dont try to do both with both
- don't deburr until the end.
- try skipping the belt, but instead do some trailing strokes (stopping) on you highest grit stone.
- if you do strop on something other than stone, try cardboard instead of the belt. Not too much pressure and an angle slightly lower (more accute) than the edge bevel.

The real value of the paper test imo is to test edge alignment and consistency.
With almost no downward pressure, draw the edge slowly along the paper and see if there are any sections that sound or feel different when they cut.

kungpao
04-17-2013, 01:23 AM
Just wanted to let everyone know that tonight I passed my test! I couldn't have done it with out the input here. I noticed my Kramer Z a little dull after cooking tonight and decided to take it to my Gesshin 5k to get things back in order. I took suggestion and used the sharpie in combination with my DSLR camera and finally truly saw what was happening when I was sharpening. Turns out I was rocking quite a bit with the traditional Japanese method of approach that I originally learned from Jon's videos on youtube.

I am a lefty when writing but am right hand dominate otherwise. I switched hands when sharpening the other side of the knife, and it felt natural and looked much better on the sharpie and DSLR test. I also stopped stropping on the belt and starting using a cork, also notice major difference straight off the bat with that. The paper push cut actually has taught me quite a bit. I can easily feel the small snags while pushing and know where my imperfection are on the blade. I feel like tonight was a break through for my sharpening. Obviously I still need tons of practice and work but notice a major difference and am very happy with the results. Thanks to everyone, and major shout out to Jon from Japanese Knife Imports for high quality stones, holder, and detailed instructional videos on youtube learned a lot from everyone! :laugh::):lol2:

panda
04-17-2013, 01:38 AM
switching hands with each side is a must for me, it just feels awkward as hell flipping it over and going same motion in same hand, besides it gets tiresome/boring that way anyway.

franzb69
04-17-2013, 01:57 AM
switching hands with each side is a must for me, it just feels awkward as hell flipping it over and going same motion in same hand, besides it gets tiresome/boring that way anyway.

i personally do both.