On Mar 3, 10:32*am, DT wrote:
In article m,

How did carpenters do this in the olden days?

One way is to use an extensions rule. Stanley made a full set of them. I
have them up to the #510, which reaches 10 feet. They are one of the old
rules I often reach for.

Extension rules have two overlapping rulers which are ruled such that
they read directly at the end of each one. They have an extendable hook
for reaching to the top of a piece. Here are some photos:

http://www.finetoolj.com/newsletter/stanley/july10.html

I'm a plane guy, not a rule guy, and I have lots of Stanley stuff, but
I never saw one of those Stanley extension rules before. Thanks for
posting that.

R