I have used PVC pipe and I invested in one "flower" tube mold so far. I really like them. Sometimes it is a b!tch to get the soap out. For some molds I spray a little candle mold release spray, it helps. I'm going to TRY to post a little pic here of the violet soap I made using this tube mold, but not sure if it'll work. I used a straw to hold the soap out of the center and filled the hole with a different colored soap. If I remember correctly, it was difficult getting it out of the tube and the end ended up all smashed but I didn't need the full length to put into the loaf mold, so I lucked out.
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