I am trying to engrave a set of polished head covers for a client and I don't understand why I am having problems getting it to engrave. It starts out just fine but then stops engraving after about 1/16". Do I need to put something on the valve cover to avoid the fine polish. I have the same settings in a test with word "test" and it engraved fine a piece of anodized aluminum. The anodized aluminum was blue if that makes any difference. I'm using my 110 lens so I can get the engraving to the size the client requested. Any ideas? In the picture you can see where it started to engrave the logo and then stopped.

Thanks
Terry Wade

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