- 1). Locate the cork mutes. These mutes are oblong cork pieces that are stuck on the top, or funnel part, of the trombone mute.
- 2). Remove the old cork mutes. With wear, cork mutes can often break off or start to crumble. Gently remove old cork pieces with sandpaper. Carefully sand down the cork pieces as low as possible without damaging the metal of the mute.
- 3). Saturate a rag with rubbing alcohol. Scrub the cork mute residue and glue to remove the remaining spots.
- 4). Wipe off the trombone mute with a clean rag.
- 5). Apply cork mute glue to the new cork pieces and affix them to the trombone mute.
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