Thakkrad Sigmundson is a Fremennik craftsman from Neitiznot. He is located in the building directly south of the bank on the island, standing in the south-western corner of the burgher's room.
He can cure yak-hides for 5 coins each to make cured yak-hides. To do this players must have started the The Fremennik Isles up to the point where they are preparing for the fight. After the quest, players can have him cure yak-hides by right clicking him and selecting Craft-Goods. An alternative method is to use yak-hide on him which can skip one dialogue screen.