Deburring on cork

[Sambal]

What am I doing wrong?

After sharpening, finishing up with Rika 5000, careful checking for burrs (by touch and with a loupe), further touch up if I see a wire edge or burr, strop on plain leather, and then on a couple of occasions for good measure I deburr on a wine cork as well. And after cutting on the cork to deburr I get a noticeable burr back!

This has happened to my Heiji and Shig gyutos and Watanabe nakiri.

Why do I deburr on cork after stropping? Yes I agree, redundant - just being a bit obsessive. Do I hear OC? Sure, many here would be familiar with this!

But why do I get the burr back after deburring on cork? Too thin an edge (I try to do around 10 to 12 degrees each side)? Deburring on cork too hard (I draw cut on the cork about 3mm deep from heel to tip)? There's a wire edge left that I couldn't detect (I do inspect very carefully and touch up even with the smallest bit of burr I detect)?

Expert help would be gratefully accepted - this has driven me nuts! Please tell me what's going on?

 

[Benuser]

In your case the cork reveals an existing burr. Abrade the burr by strokes along the edge.

 

[schanop]

What Ben said. I used to have similar issue when I started. Basically, edge was too fragile either it was the actual burr, fatigued metal, too thin edge, or combination of those.

 

[malexthekid]

I'm not familiar with stropping on leather etc. But I have found Jon's method (JKI youtube channel) to work very well of stropping on your final stone. Touch wood I haven't had any issue with burr removal so far.

And I follow that up with cutting through cork, or using a tea towel for a few extra "stropping" strokes.

 

[Sambal]

OK thanks guys. Back to the drawing . . . stone.

I still don't understand how deburring on cork would reveal an existing burr as Benuser said though. Isn't this process supposed to get rid of the burr? Could my problem be, as Schanop suggested, too thin/weak an edge that gets degraded when I deburr on cork? If so what to do? Higher angle?

 

[Sambal]

I have to mention that the burr that comes up after deburring on cork is a surprisingly large one, something like a thick wire edge.

 

[Mrmnms]

You might try starting with the cork earlier in your progression rather than just on the 5k

 

[chinacats]

You might try starting with the cork earlier in your progression rather than just on the 5k

+1 You need to completely remove the burr at each stage before moving along and if you are realizing that big a burr at the end, it likely came from a prior stone. Not sure about why it shows up when it does on the cork, but don't think it's too important why/when; moreso that you figure out how to remove it.

 

[Geo87]

Benuser had some advice for me along time ago which helped me a lot: don't think of it as removing the burr, think of it as abrading the burr.

Some burrs won't just fall off easily particularly if you have a huge one left from a coarse stone. try abrading the burr a bit after your coarser stones before moving on to polishing stones. Edge trailing strokes with no pressure and lateral strokes (like on jons deburring video ) work well.

 

[Sambal]

Thanks y'all.

I usually do deburr at every stone step but I guess I must not have done this well enough, thinking I can clean up properly at the final stage. So I'll try deburring better after every grit step. I'll also watch Jon's video again. (Thanks Jon, your vids are really such great instructional pieces! And so generously given too.)

Any other deburring videos I should learn from?

 

[chinacats]

Thanks y'all.

I usually do deburr at every stone step but I guess I must not have done this well enough, thinking I can clean up properly at the final stage. So I'll try deburring better after every grit step. I'll also watch Jon's video again. (Thanks Jon, your vids are really such great instructional pieces! And so generously given too.)

Any other deburring videos I should learn from?

Jon's videos are awesome. If you haven't seen them, Dave Martell has an old three part video still floating around. Also check Rick's (theory) videos and finally Murray Carter's cinder block and cardboard demo.

 

[mhpr262]

I usually deburr my knives on a bit of balsa wood that has been smeared with some polishng compound for buffing wheels (works well when you apply some heat). So far I have found nothing better and it costs just a few cents.

 

[toddnmd]

Jon's videos are great. I bought Murray Carter's sharpening video, and think it was a good purchase.

 

[cheflivengood]

3mm in the cork sounds like too much pressure, only use the weight of the knife and draw back with only your thumb and pointer finger ( this helps use only the knifes weight). careful because the tip will fall so dont do it over something hard or your skin.