It does work. However if you have some form of horn dust to mix in it would be better. Be careful, just sanding horn on a piece of sand paper will give you broken abrasive parts too. They do show up. I have used plain Acra-glass liquid for this process with good results. Just go slowly and do not be afraid of making many applications if you have multiple holes. You may not get all of them filled the first time, or they may be in a wrong angle to best fill the hole the first time around. Mix small batches for best results.