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Thread: Suggested starting angle to sharpen new Tojiro DP Gyuto and Petty?

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    Senior Member GeneH's Avatar
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    Suggested starting angle to sharpen new Tojiro DP Gyuto and Petty?

    I have a new Tojiro DP 180mm Gyuto and a 120mm Petty waiting for me when I get home from the office in a couple hours. Assuming I can improve the bevel, how shallow should I take it? This will be a straight V, not convexed. I guess this VG10 core is about a 60-something in the rockwell scale, so does it perform better a little toothy (about 1500 grit, sorry don't have the micron size) or should I smooth it out a bit for starters?

  2. #2
    According to Tojiro the factory angle is between 9 and 12 degrees. Lay a straight edge across each side to see if it's 50/50 or asymmetric.

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    tojiro dp's are said on their website to be 60/40 righty biased. but it really depends on how it's made if it's machine sharpened or hand sharpened. i'd follow what mike9 said.

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    Senior Member GeneH's Avatar
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    Quote Originally Posted by franzb69 View Post
    tojiro dp's are said on their website to be 60/40 righty biased. but it really depends on how it's made if it's machine sharpened or hand sharpened. i'd follow what mike9 said.

    Yikes! I thought they were 50/50 symmetrical blades. I'm a lefty. If it's just the cutting bevel that's biased, I can fix that but not if the whole blade is asymmetrical.

  5. #5
    you can make it 50/50 with no problem or even 60/40 lefty. It will take some work but if you new i would just follow bevels until your comfortable. Watch theorys sharpening gyuto video it explains how you sharpen until you get a burr then flip rather than counting strokes and really is the best way to sharpen.

    If the blade is asymmetrical it may cause sticking on the left side.

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    Senior Member Benuser's Avatar
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    The difference between a 60/40 and a 50/50 is barely perceptible. Would it steer - which is not very likely - I would suggest to convex the left side a bit by thinning behind the edge, and loosen your grip.

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    Senior Member GeneH's Avatar
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    So - How do I tell if the blade, (not the bevel) is symmetrical or not? Do I use the flat side of the handle as a reference? That doesn't sound reliable to me. I'm outa my league here.

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    Senior Member stevenStefano's Avatar
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    I used to find it tricky but not now. Hold it up blade side up and look at it down the choil if you get me. Does one side of the knife look different to the other? If it's 50/50 clearly the sides will look the same but if one side is convex (more rounded) and the other is flat then that shows an asymmetric grind. If you take a photo it would help. I've got a DP damascus and it looks 50/50 to me or close

  9. #9
    Senior Member GeneH's Avatar
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    Quote Originally Posted by franzb69 View Post
    tojiro dp's are said on their website to be 60/40 righty biased. but it really depends on how it's made if it's machine sharpened or hand sharpened. i'd follow what mike9 said.
    I think I found the info you are referring to, "In our factory we edge the blade 60% to the right and 40% to the left, because it is quite difficult to edge fifty-fifty by standard grinding. However it is also possible to edge conversely upon request." http://tojiro.net/en/guide/part_edge.html

    Since it is the edge being discussed, I'm good with that. Easy enough to change, but if the factory has a problem getting and even 50/50 edge, I doubt I could do better. Why would a company say it's "quite difficult" so they proclaim 60/40? Sounds like just a way to justify an uneven bevel, so bias it on purpose one direction.

    The knives arrived - wooohooo! For the life if me I cannot see that the blade itself is asymmetrical. They are the F807 and F801 Western style.
    Last edited by GeneH; 05-13-2013 at 04:39 PM. Reason: 'cause I can't get it right the first time...

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    Did you ever measure that factory angle? I'm skeptical that a Tojiro would have a 9-12 angle, I would think closer to 15.

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