Use a damaged chitin with a hammer on an anvil to receive chitin scraps. The number of scraps received depends on your smithing level.
Used to repair Drygore weapons.
At level 60 Smithing, 21 scraps are received for breaking down damaged chitin. This increases by 0.5 for each additional Smithing level past 60, and is rounded down. For example a player with 99 Smithing will obtain 40 chitin scraps for breaking down one damaged chitin.