Toy thermometer with movable "mercury" column(made from piece of red filament). Print with no support - they will block the channel.

Prusa

i3 MK3

No

No

0.8

100

Clean "mercury" channel with a knife. Take piece of red filament, straighten and sharpen the end, insert one end into "mercury" channel, another end in the box with a hole in the middle of thermometer. If the fit is too loose then flatten red filament with pliers in a couple of places.

Print "thermometer_scale.ods", cut and glue paper scale. Fasten it to the wall.

If you want to generate your own scale then use OpenOffice Macros from attached "thermometer.txt" file.