Two clamps to use a set of welding clamps the ones with pads looks like vise grips with c clamp on the end. The other is a carpenters vise lowe and Harbor Freight has them for 20.00 mount it on bench. i have bought all kind of clamps and these are the best and don't rough your molds up. I don't heat my molds but i heat my injector and blending block after u get plastic to 350F let it drop to 300f then inject i would melt some scrap and use it till i got it down pat. I have a pancake grill i set my injector on to heat it the hot plate maybe getting it too hot in spots and melting your orings i set my grill on about 200f to warm my injector. Draw into injector slow and push into molds slow and steady. Cub48