The log mold is an hdpe mold and yes they can leak. Especially the small ones made from thin hdpe because they can and will warp with from heat. It looks like the one from Michael's Craft Store. Just for future reference it will hold 39 oz total batter, so if you use soapcalc just check your total batch weight after all the liquids are added in. (Soap Weight before CP Cure). I picked up a couple of them with coupons for using as test molds, but my 2 lb much thicker hdpe mold is better. Also do not over tighten the bolts as this will cause tweaking of the sides. That could be your problem Krista, you only want to tighten hdpe enough to hold it together. I warped a few of my molds when I first started soaping by over tightening. It really is best to use a slip liner in hdpe molds although the smoothness of the Michael's mold will usually allow the soap to release.