In domestic thermos small size is screwed on top of the cap, which is often a too strong tightening the cracks or even breaks. Instead of trying to stick together, it should be replaced by a suitable diameter plastic cups.
Recommend to read
AND TO DRAW AND STORE
A thin drawing pen tool is fragile, and inserted in a normal pen, easily spoiled by careless storage. Better to use it with the handle, and with a collet Chuck: and is held securely,...
WITH COTTON — TIGHT
The surfaces are usually not only previously degreased, but cleaned with sandpaper to get the roughness that increases the strength of the connection. The same effect can be achieved if...
