hello. using the bath on the 7 insight door allows to respawn all the consumables in the game, except for blood shards. however, 1 bloodshard will be spawned randomly in the game, and this is the first one you encounter roaming through the map. in fact, if you go from the hunters dream to central yarnham and then directly into the villa on the left, then all down to the basement, you'll find 2 or 3 twin bloodshard which are spawn due to the bath. normal blood shards can be farmed from the bloody werewolf near the great bonfire lantern. twin blood shards instead with the bath trick. therefore you can get all the weapons at +4. however the only way to max out 1 weapon is to go in new game plus.