I think that there is just a difference in quality due to the lower price. I have a lot of cheap imported tools that just don't work but kind of live with it, since the price was so low. In this case, I would just try to find the high spot and find out why it is scratching. It may just be a hard spot in the casting, and can be gently persuaded to not be so sharp and proud. I wouldn't return the product. It's a really good lesson, and one that you can well afford to repeat. Just try to make things sort of work. I have posted a few examples, and I'll report some of them here. I bought some Harbor Freight diamond cutoff wheels. I discovered that they would only cut a tiny bit on their perimeter before the thin layer of diamond grit wore away. The disks had plenty of diamonds on their faces for the customer to see, but those did no good for cutting. They were there for cosmetic purposes only. At least the cutters can be used to do some tool grinding, but there aren't really enough diamonds to do much good. I thought the mandrels could be repurposed, but the cheap screw stripped out immediately. I'll never buy these again, but I won't return them. This will cause me to repeat unwanted behavior. I bought a carbide tipped dead center for my lathe from Ebay. I ended up getting sent a mild steel tipped dead center. I know it is mild steel since I gingerly did a file test. I complained to the seller, and they insisted that I send lots of photographic evidence including the file marks. When I sent the photos, they asked me if I would be happy if they returned $1. I said OK. These lathes can do a lot of good work, but as a lot of people on the Internet say, they have shortcomings that need some refinement by the consumer.
