The only time I didn't cover the sinew with snakeskins, then poly, I just used the poly directly on the sinew...after it had dried for months and been smoothed. I actually stained it between sanding and sealing, but let it dry again after staining. The good thing about spray can poly is that you can easily apply more later on, or you can rub on a little car wax or bear grease/beeswax. No matter what you use, covering the sinew with snake or rawhide before sealing works best I think.