As part of the discussion that was brought up here about the Kinshiro gauges, I went out to stu's page and to ebay and looked around at the options for mortise marking gauges. Long ago, I had bought one of the really cheap gauges from japan woodworker and decided that it was not worth the trouble to clean up (likely something I wouldn't conclude now, but I didn't know what to do back then to get the blades to slide over each other freely).
So I bought the gauge that costs about $130 on stu's page because it looked like it would mark narrow mortises, and then went out to ebay. I found this gauge. I didn't know anything about it other than that it looked honest, it was cheap, and the irons appear to be very well made. I'd presume this was a workman's grade gauge that came out of miki in droves, but not at $17 like the really inexpensive gauges. After ordering it, the lady doing the sale said her husband had used it and he was a professional. The way the irons are sharpened suggests it, too. You can't see in the picture, but the bevels are perfectly flat and the knife edges are perfectly clean and sharp with no nicks or damage.
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look at those irons!! I bought it for $28, figuring that if the wood was junked in any way shape or form, I could just remake a gauge and those two irons would be worth the cost of admission.
$_57.jpg
It will definitely mark a 6mm mortise, which is the smallest size I normally make. Everything on it is slick just like you'd expect it to be if a professional was using it, the irons are super smooth adjusting against each other and the gauge. And it marks a mortise much more easily than my pin gauge. Kind of wish I hadn't spent $130 on a new one!!
I guess the moral is if you're sometimes cheap like me, look for these on peebay - they don't bring much, and this gauge can't be far off from a really high dollar gauge when it comes to function. And it's shape (and how properly it's maintained) has something to do with the fact that it was used by a professional and not experimented on by someone getting their first gauge.