constructing a standing tank with filled 60L tanks voids the contents about cataclysm-dda HOT 4 OPEN

I believe this has been reported before.

The reason is that the tank is just an item that's deleted from the world when the construction is finished, and nobody has written any code to deal with any potential contents (there is such code for crafting (by emptying the contents), but not for construction).
Any logic to carry contained items over into a constructed furniture/terrain/appliance would have to deal with the issue of contents not accepted into the "pocket" of the new thing, as well as the case where it would require mixing of items.

Note that the above is not me saying things shouldn't be improved, just trying to explain why it is the way it currently is.

from cataclysm-dda.

it might be possible to reuse the container emptying ui if that happens
say i try make a tank using water and vinegar 60L tanks
it first asks what liquid to store in the tank, then for every other liquid used brings up the transfer ui to move it somewhere else or dump it on the floor

from cataclysm-dda.

It would probably have to be a copy rather than reuse due to how UI and code is intertwined like spaghetti, and you'd still have the same problem as crafting does when performed by a companion (but it would still be an improvement).

from cataclysm-dda.

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. Please do not bump or comment on this issue unless you are actively working on it. Stale issues, and stale issues that are closed are still considered.

from cataclysm-dda.