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View Full Version : Pine endgrain paring test for chisel sharpness



Brad Swanson
07-07-2015, 10:02 PM
Just finished flattening/sharpening/honing some new Koyamaichi oire nomi at 30 degrees (Shapton 1k ->5k -> 8k -> green compound on leather strop). Took one of the chisels to some Borg pine and made a quick video. Curious if the performance shown in the video is considered acceptable or not for the endgrain test. https://youtu.be/QyMdYvHv-YU Thanks.

Brad

Harold Burrell
07-07-2015, 10:29 PM
It is kind of hard to tell. But from what I can see, it looks good to me. What I look for are "shavings" and not "scrapings".

Kees Heiden
07-08-2015, 3:29 AM
You should also look at the surface left behind. Pine endgrain is difficult because you have hard and soft layers next to each other. So with a dull edge you can cut the hard layer but you are crumbling the soft tissue in between. A sharp edge leaves a waxy looking smooth surface.

Brad Swanson
07-08-2015, 6:27 AM
Yea surface left behind is glossy/waxy. I think I'm there.

David Ragan
07-08-2015, 7:14 AM
I use three methods-
1) my favorite, is shaving hair off my forearm. Gives me a very tactile feel all way around.
2) holding the edge up to the light. Any reflection off the very edge is bad.
3) the least sensitive for detecting a high level of 'sharpness' is the thumbnail test, IMO.

Great advise to look @ the end grain left behind.

Daniel Rode
07-08-2015, 9:23 AM
I'm no expert on sharpness but that's how I test my chisels. If the chisel shaves pine end grain, it's sharp enough for my needs. I like the feedback from this test. By how (or if) it slices through the end grain, I have a good idea how it will perform or if I need to go back to the stones.

Allen Jordan
07-08-2015, 1:08 PM
A good sharpness test is slicing standard printer paper. If you can slice both the long and short sides (short sides are usually harder because of the "grain" of the paper) cleanly, you're good.

Brad Swanson
07-08-2015, 2:15 PM
Indeed, I've filled-up the recycling bin slicing perfectly good 20 lb laser printer paper with the sharpened chisels. They push through the paper with minimal force and cut cleanly.

Tom M King
07-08-2015, 3:14 PM
317008317009It doesn't have to be endgrain to tell-just any scrap laying around if you have to test it. Had these pictures already in here. Large shaving is from a block plane. Tiny ones were too fragile to measure. They aren't very wide because the piece the chisel is being shown on are tenon cheek offcuts from a backsaw, so the surface is not perfectly flat from the saw teeth. Mic is on the block plane shaving in the first picture.

Jebediah Eckert
07-08-2015, 3:18 PM
Wow! I didn't even know they made anything electronic that can measure down to .00005 I picked up a used Starret digital caliper that goes to .001 I may have to up my game now that I know it exists ;)

Tom M King
07-08-2015, 3:33 PM
I think I've had that one since the '80s or maybe '90s at the latest. It was when Mitu was considered decent cheap measuring stuff. Whenever it was, I kind of remember paying around 45 bucks for it new.

edited to add: It might have even been a gift. In any case, I've had it so long that I don't remember exactly when I got it, or under what circumstances.

Patrick Harper
07-09-2015, 9:18 AM
Looks good to me. It's more about the surface left behind, and it sounds like you nailed it. What's the song in the background?

Brad Swanson
07-09-2015, 10:22 AM
Patrick,
That's Gillian Welch (and David Rawlings). Here's a live vid recording. https://www.youtube.com/watch?v=9NPEj63d0jY They are absolutely brilliant, my faves when it comes to folk/Americana.