So if you read this you’ll know why I decided to gut my folding rule. I’ve been playing with the idea of making these rules from scratch and after my restoration debacle I figured I’d take a closer look at how Stanley made theirs. Disclaimer: I am not a folding rule expert, these are simply the observations I made while examining the only #62 rule I had at my disposal.
First, some overall dimensions. The length of a 4 fold rule is 24″ broken into four equal sections (6″ per section, duh). Each section 1/2″ wide and 11/64″ thick (I think 11/64″ is an unusual number to land on, but it was exactly that dimension and it does feel correct in use, so 11/64″ it is).
The binding is made from strips of brass that were slightly over 1/32″ thick. They are held to the wooden body with steel pins (~1/16″ diameter) that run through the entire body and are deformed, or swaged, at the ends to prevent them from falling out. One thing I found curious was the location of these pins varied greatly. They were not perfectly or consistently centered along the thickness of the tool and the spacing between pins was also very inconsistent (it averages around 1-1/4″). There were, however, five pins used per section so at least that was constant. This variability makes me assume the pinning was done manually which is surprising for the number of 4 fold rules Stanley turned out, but maybe trying to automate the placement of so many fine holes was unreasonable at that time and manual labor was just easier…
The far ends of the rule are also capped in brass, the side strips run right to the end, but a C-shaped cap is sleeved over the faces for added wear protection.
Finally the hinges. There are two types of hinges used, one for the center joint that acts like a pair of scissors and another used in two places to fold the end sections inward over the middle sections. The scissor joint used is similar to a rule joint used on tables. One section of the ruler has a brass plate pinned to both faces. This is the only time brass pins were used instead of steel. The brass pins are virtually invisible which means they won’t distract the user when reading the markings on the face. These outer plates are sandwhiched (if that’s a word) over a thick piece a brass attached to the opposite half of the rule. The layers are then pinned in the middle and the joint if free to rotate.
The two folding joints are similar, but not the same. There are again two outer strips of brass attached to one section of the rule (it’s actually just part of the edge banding), but the opposing section then has extra brass strips added below the surface of the edge banding. These extend about 5/8″ into the body of the rule and are pinned. Finally, a floating brass barrel takes up the space between the upper and lower brass strips. A steel pin passes through the joint.
The final step would be to add the markings which would be challenging without a stamp. Lasers don’t cooperate with brass and any form of “painted on” markings would wear off, especially where the brass needs marking. A difficult tool to make properly for sure, especially in small batches. As I said in my last post, it’s back to the vintage market to find a functional #62 for the shop.
Have a great day.