Well, I went ahead and tested it.
Since you did not name the version you’re playing on, I’ve picked a random one I just happend to have (experimental 2021-06-13-0522).
This is how it went:
Spring, Day 81, a little before 17:00 (no splint):
My broken limb shows as ~~%~~
(color: red) in the sidebar.
The player info menu lists it as “Disabled”.
Day 81, 17:00 (with splint):
Sidebar: -----
(color: blue)
Info: “Disabled”, as well as “Started recovery”
... more progress
Day 82, 14:00 (with splint):
Sidebar: #----
(color: blue)
Info: “Disabled” + “Started recovery”
Day 83, ~23:00 (with splint):
Sidebar: ##---
(color: blue)
Info: “Disabled” + “Recovering”
Day 84, ~10:30 (with splint):
Sidebar: ###--
(color: blue)
Info: “Disabled” + “Mostly recovered”
Day 85, ~18:00 (with splint):
Sidebar: ####-
(color: blue)
Info: “Disabled” + “Mostly recovered”
Day 87, 13:00 (with splint):
Sidebar: :....
(color: red)
Messages in the log: Your [BODYPART] has started to mend! (color: green) & The broken limb has mended. (color: green)
Info: [Nothing]
To make my test as accurate as possible, I took off my clothes to stay as cool as possible (I did the same thing for the character ). The temperature of the limb bounced between 2 and -43 and stayed at -20 to -30 for the most time, so your -32 should not have had any influence on the healing process (unless you dip into damaging ranges).
As shown, it took around a week to mend the limb, and whatever time it takes to fully heal from :....
to |||||
.
I did have some factors that did benefit the healing progress, like having enough to eat/drink and I let my character sleep alot (I’d like to do that too, at some point).
I did walk around, and chased and killed some birds as well with no problems. I’ve taken care that my broken limb did not take any more damage though, as that could/will throw you back quite a bit in the recovery process.
So, it seems to work as stated; it takes around 10 days to mend. So, the question remains; what message did you see? Or even easier; what symbols are shown in the sidebar?
For the sake of completion, the following affects the healing rates (in the current versions):
Mending factors
Negative:
- Smoking and Alcohol, and their addictions.
- Being radioactive (unless you’ve mutated the Radiogenic trait).
- Being
Dead tired
or worse.
- Being
Very hungry
and Very thirsty
or worse.
- Having a low health stat.
- Some mutations.
- Taking damage on the broken limb (actually reverses progress).
Positive:
- Sleeping/Resting.
- Enough stored fat & water.
- Having a high health stat.
- Some mutations.