hey everyone,
I am here for a very specific reason and I am hoping someone can help. I am looking to identify the use of an old Proportional compass which was made in the U.K. back in 1920. It has scales in feet, chains, and miles. I am not sure where best to post a question wit photos about getting more specific information on it's use. As an architect I have used these for drafting, but this is something outside of my normal drafting sphere.?ÿ
?ÿ
Any help would be appreciate.
?ÿ
Robert
?ÿ
The numbers probably refer to common mapping scales in miles per inch or whatever. From the UK, the scales may relate to the Ordinance Survey maps. But you should be able to set them to any proporton you find useful.
http://engineeringtraining.tpub.com/14069/css/Proportional-Dividers-72.htm
This link covers a lot more, but has a section on using them to make a drawing at a different scale from an original.
https://thedesignersassistant.com/tag/proportional-dividers/