I create this Ikea Lack box mounting for the cheap thermometer from Aliexpress. 

Thermometer link: https://www.aliexpress.com/item/32895158920.html?spm=a2g0o.order_list.order_list_main.15.26281802SKJIsN

15% fill, layer 0,15mm, supports needed for the main front space.

I just drill 5mm hole into the Lack table and I glued it with mammut glue.