Proportional Dividers. A Very Useful Tool.

A mid 20th century Alvin 450, a triangle and engineers square, and some one sixth scale miniatures.

Proportional dividers are ancient tools, dating back to Roman era, though as late as 1955 some thought they were a Renaissance invention.  The Alvin 450 is really handy when making miniatures, like the triangle and engineer’s square above, that I made for Fritz Otto Buchbinder.  They allow you to quickly see and measure what a reduction in the actual reduction size would be.  Using one is a much more intuitive than having to divide 100ths of an inch into something. But don’t get me started on numeric measuring!

 

Instructions for how to use a proportional dividers. http://lib.store.yahoo.net/lib/draftingsteals-store/proportional-divider-use.pdf

Other uses are to convert a given length of line into equal parts, divide a circle into equal parts, and even generate angles. All of which are useful for bookbinders. The 450 can generate proportions down to 10:1 for lines, and 20 :1 for circles. A regular dividers can do these things, but it takes some set up time.

They make a great addition to my  dividers collection.  I found them at a flea market, still in a fake leather covered wooden box, with a nifty sliding pin latch, all for $10. They originally sold for $9.75, so they have held their value. New ones are still available, though considerably more costly, having a list price of $216, though commonly found for $132.

Obviously, though, one can never have too many tools. I’m still looking for a used 458 (10 inches long) and a 950 (stainless steel)….

To Describe a Heart

heart
R. Moore The Artisans’ Guide and Everybody’s Assistant: Containing over Three Thousand New and Valuable Receipts and Tables (Montreal: Printed by John Lovell, 1873) My Collection.

Dividers; or, What Problem?

stevens dividers

Some of my dividers.  

Sara Bryant of Big Jump Press wrote a breathlessly enthusiastic ode to dividers last month on her blog. Apart from extolling the virtues of comparison measurement, she wondered aloud if she perhaps was becoming a hoarder beause she has six pairs, and if it might be a problem.

My dear Sara, rest assured, you do not have a problem.

stevens divider

My favorite dividers, a 19th century Stevens & Co. Note the unusual, and extremely elegant position of the adjustment screw above the pivot point.