Question: does a liquid or gelatinous substance exist that once outside a body could solidify and be hard enough to be used once as a tool?
The setting is low fantasy without magic, yet with creatures that went down a different path in evolution due to hard environmental pressure.
What I want to achieve
I want a creature to be able to make impromptu tools with materials from inside their body. The solidifying process should start once excreted and be done in seconds or minutes, hours would kill my intentions. They result does not need to be durable, a single use is enough. Basically a biological prototype 3d printer with limited use.
Is that possible without making up some fantasy substance/material? I looked into crystals and solidification but didn't find anything convincing. Sadly they take way too long to form.
If such a substance exists it would be nice if you could state whether there are conditions that need to be met like pressure, heat/cold/electricity or some kind of material that the creature must ingest. The creature can have some special attributes in order to meet these conditions but this is for me to handle.
Im kinda worried that such a solidifying process would generate heat or somewhat pain but im not knowledgeable in this field.
EDIT: Mixing two substances or adding another external factor to harden is a legit approach. Most important is the hardening speed as it needs to be solid in seconds. The result can be crude and only useable once. Fine Detail is not needed. This process would not replace the normal way of making objects, but help in special situations.