SMHAEN Master Dubbing Twister

I bought this item some time ago, but just recently used it. After looping the thread through the hook, twisting dubbing and starting to wrap the thread would consistently break where secured in the hook. After checking online I noticed that others have had the same problem. And I ultimately found ragged hook edges. I contacted Smhaen and they suggested lightly sanding the edges with 500 grit sandpaper or covering the hook edges with shrink tubing (though Smhaen couldn't tell me what size). They did say I could return it to them. They did not even offer to pay for shipping. Well, this is a pricey dubbing twister and it should never have left the factory if it was not perfect. I have purchased the sandpaper and shrink tubing is supposed to arrive tomorrow. Customers should not have to repair manufacturing defects. Inferior product and terrible customer service. I will never buy another Smhaen product.