I'm using the materials_overwrites.cfg file to change wood's harvest level to -1. Vanilla tools do what I want but Tinkers' tools stay at the regular wood mining level and are still able to mine blocks that my vanilla tools can't.

Sorry for the late answer.

Tools from Tinkers' Construct only read the configuration when they are created. After that point, the harvest level is stored on a per tool basis. So if you change the harvest level based on materials, you have to create new tools in order for the change to have an effect.

I've tried doing what you describe, making the changes, loading up the game and making new tinkers tools but they don't do as I'd expect.

Maybe I'm missing something?

These are the changes I've made to the config files:

block_overwrites.txt
materials_overwrites.txt

But I can still use the wooden tinkers' tools on logs and stone.

On further investigation it seems like some of the Tinkers' tools did actually pick up the new setting while others didn't. I crafted a whole set of wooden tools at the same time and only the Hammer and Mattock are working as I would expect, they can't mine stone or cut wood. All the other tools still show "Mining Level: Wood".

EDIT:

Interesting. I'll look into it.

Tinkers Construct doesn't allow the creation of tools with a harvest level less than zero. I may be able to override this, but as a workaround, you also could increase the harvest level of stones.

Just out of curiosity, what are you trying to achieve?

I want to make wooden tools useless basically. I'm trying to change the progression of things a bit. But that's good to know, I'll need to workaround that.

Maybe a totally different approach: Try to disable the creation of wooden tools, though I'm not sure, if crafttweaker can modify the recipes for the TiC part table (or however the thing is called, which allows to create the tool parts)

As I can't do something from my side, I'll close this issue.