If you're talking about the English whittlers there's actually quite a bit more room to work with in that blade well then on the 68 owls. It's quite a bit tighter in there. Pics below for comparison.
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Now if it was the Grinling 38s you were referring to. Well that's on another level all together.
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Now I'm not making excuses for anyone but if they were to take the time to fine tune everyone of them to eliminate the rub I think we'd be expected to pay the likes of secondary prices instead for these.
I think the tang of the pen scrapes just past the tip of the main as it's opening. That tight space coupled with the pressure put on the nick to pull that secondary up might just be enough to get them to touch when they shouldn't. I have an example of both with and without the scratch there. I think it just how it goes with these.
The ugly stag I've noticed on a few.... Ive got nothing lol