Mmmm that's strange, maybe another mod is making an interference with this one, try to put this one higher on the mod list, doesn't have any sense. You don't need any DLC I don't have either

i tried it with no other mods enabled as well and had the same result

omg that's strange, I can't replicate the bug, I will update the SDK and reupload, I don't know what to say.

I've got the same Problem. Did you found out anything, is there a fix in sight? thank you.

No, sorry Beliar but I don't know why is this happening to both of you. If it's not because of another mods I don't know where the bug comes from, he was using the improved blacksmith bench, try to use the regular bench. If works on the regular bench I know why is this happening, but I can not think anything better.

I found the solution. It's unbelieveble. After ive got several problems on my server (couldnt skin some animals, couldnt get elephant hide) I found out that the following mod caused all the problems:

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=1286995920&searchtext=weapons

After uninstalling it everything worked fine again, and when i reinstalled your katana mod, it worked! So its not your fault. its the other developers fault. just wanted to say that. Thank you for your cool mod, maybe you can share this to help other people who have the same problem like I had. THANKS :)

Oh!! Thank you for your research! I will notice on the mod description.

JUST IN CASE: The mod was designed to be crafted on the regular Blacksmith station