For those of you who won’t be able to attend Handworks in May, you can still find yourself a pair of Studley-like calipers for your shop with the help of the always-digging Jeff Burks.
Jeff did a little research on the so-called “register” calipers, which is the name that some manufacturers (but not all) used for this tool. Below are a good number of links that will help you search for the different brands.
The best link? The last one. It’s to a Japanese company that still makes this tool. Stainless steel. Several sizes. Hardened tips.
The good news on the manufacturing front is that we are hopeful that a modern toolmaker will produce these for sale. The company borrowed our prototype and all our photos and measurements from the Studley version. So keep your fingers crossed.
I’ve been using our prototype in the shop for many months and find it to be a useful apron tool for handwork.
For the most part, I use it as an “adjustable mullet” – there’s a thumbscrew on the back of the tool that locks in a particular thickness. So when I’m raising a panel by hand, I lock the caliper at the groove’s width and use the caliper to determine when I’m finished.
I use the same basic procedure when cutting rabbets and surfacing stock by hand.
You can, of course, use a locking dial caliper to do the same job. Or a block of wood. This is just another way to do it.
— Christopher Schwarz
Links from Jeff Burks:
Illustrated Catalogue of General Machinery and Supplies – Cooke and Co., 1883
A book of tools: Chas. A. Strelinger & Company, 1896
1890 Seeger and Guernsey’s Cyclopaedia of the Manufactures and Products of
the United States has a listing for all the caliper manufacturers in the
U.S. (Scroll to bottom) One of these companies likely made the Studley
Using that list I found an auction for a register caliper on Worthpoint. The style matches the Studley caliper, though it appears to be one of the larger versions. This one was stamped with the name Wm. Johnson Newark NJ. This company was founded in 1834 and operated from a building complex called the Hedenberg Works.
1898 G.W. Davis patent register caliper that piggybacks the earlier design.
1899 Seeger and Guernsey’s added a category for register calipers with one company: Kraeuter Co. Newark, NJ – founded 1860 and also operated from the Hedenberg
Several books printed after 1900 contain illustrations of the register caliper:
1906 Henley’s Encyclopaedia of Practical Engineering.
Niigata Seiki of Japan currently manufactures a stainless steel version of the register caliper under the SK brand name. They are available in multiple sizes with metric graduations and hardened tips.