Have a drink of water.
Leave it in the sun !
as a draftsman, one comes to work in the morning,
and has to retension the Drawing, after lunch , at about 2 oclock all the tape pings of.,
as its shrunk again in the sun.
So some silly twit ivents plastic paper which is more thermally stable, and wears out pen nibs and has other foibles.
then someone invents air- conditioning 7 legioneers disease.
Its caused by Moisture temprature variations.
the plan bit.
Legioneers disease is like worn out automotive engines.Its caused by dirty filters.
You could put the Air co unit from the printers in your workshop, and the plan should be the right size.
Or visit differnt states with the plan, a steel ruler, and a calculator and log of expansion rates for steel rulers,
If you want to get it spot on .. . . .
Ananamus.
( Gees, it takes a bit to get you blokes to bite , doesnt it )
a bit of latteral thinking encourages alterative solutions ,
development of the concepts etc. . .