Who markets the scale rules shown on page 67 of Vance Bass' article " How To Choose a Scale" and the cover of Oct. 2011 Garden Railways?
www.thescalecard.com
Another very good tool I have found is "handy converter". I bought it about 12 months ago and have found it excellent.
The title is - Stan's handy converter for the model railroader.
www.StansTrains.com Have a look at the demo model on his website
Regards Andrew, Sandbar & Mudcrab Railway
Those were made by C.T.T in Texas. They have been discontinued. http://www.thescalecard.com has scale rulers. http://www.rulers-of-the-world.com is another source. Here is a link to some printable rulers. http://www.hungrylizardstudio.com/ssm/scalerulers.html
Tom
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