For example, when i made a stone frypan it's damagetype is 100% bludgeoning.But when i change the pan_head into a firewood one, it's damage is still bludgeoning but it should be fire.

I assume you found a fix or realized what was going on but I was unable to replicate exactly what you've described. Using the default values, swapping a stone frypan head for a firewood one results in a 20% bludgeoning and 80% fire distribution

I assume you found a fix or realized what was going on but I was unable to replicate exactly what you've described. Using the default values, swapping a stone frypan head for a firewood one results in a 20% bludgeoning and 80% fire distribution

sorry for not replying for a long time, I consumed a lot of time testing what's the excat problem.
The problem is, for example, under default config, if I build an iron broadsword from tconstruct, its damage distribution is slashing 100%, and I change its head part into firewood ,its damagetype become fire 100%. But when I change its head part back into iron, its damage distribution should become slashing 100%, but the distribution won't turn from fire back to slashing immediately, sometimes the broadsword would keep making fire 100% whichever material I put as the head part. I only put ddd,mantle and tconstruct in my modpack

From all my testing and tweaks I have been unable to recreate this. Check on the latest release (1.7). Please reopen if you get the problem in the latest release

From all my testing and tweaks I have been unable to recreate this. Check on the latest release (1.7). Please reopen if you get the problem in the latest release

I tried 1.7 version, and if the modlist still only contain ddd,mantle and tconstruct, the damage distribution work properly.But once I put a tinker's addon( I tried
plustic and tinkers'reforged) and I enter an existing world,
after a tool's head part was changed into firewood, it's damagedistribution is fixed to fire100% and won't change no matter what its head part is changed into any material.