How can I repair an endpin where the wooden ring has been stripped by the screw? I cant quite explain it....lthe wooden ring isnt cracked or anything, but the screw keeps on turning and wont hold the endpin in place...theres also a metal ring surrounding the wooden ring where the screw goes... I dont have money for a new endpin or money to take it to the shop. Sorry if the question is badly written. thanks. any help is appreciated.