Hey...I can proudly say that I finally got the knack for getting smooth tops, so noe I can speak on the subject, unlike before. I also use OK6228 and found that in order for the sides not to look frosted or rustic like, I had to heat the molds a tad. In addition, I did three pours, instead of two and I finally got the beautiful tops I've been striving for. First pour, I'd pour just under the lip of the mold, then when that shrunk up completely, I'd pour into the shrink hole just so it filled to the original pour line, then the third pour would top it off, with no shrinkage and a beautiful smooth top. I know it's more work, but it's the only way I could finally get what I was looking for and besides, I don't make a whole lot of them, only for my own use, so time is not an issue for me.