Here's just a little tid-bit that I discovered about the new Thump-It molds. Nothing serious, but it does affect how you clamp.
The molds are smallish but they do need two clamps especially one centered top to bottom right over the sprue and the other straight behind it. While it seems like over-kill, both molds can flash and/or blow out if even a little too much injector pressure is used. This isn't a real problem with either of those I have but this morning I thought with the shop being cold I might need to bump up the pressure and hold time just a hair to get good welds on some tails. I had the molds stacked back to back and one clamp used. Wrongo. After re-claiming the tails and doing a second shot, again with the molds stacked, this time double clamped I had success.
Just something to watch for. Nothing at all a second clamp won't cure.