I am new to 3D printing and to this form. I just got a PowerSpec 3Dpro printer and I am using ReplicatorG to open the .stl files and print. So far I have been able to print a few small things with a somewhat less than exciting level of success but the reason for this post is that I am not able to figure out how to use the 2nd head on the printer. What I would like to do is load the PLA into the right head and load some water solvable material in the left head. When printing I would like it to use the PLA for the model and use the water solvable material as the support structure. I was thinking that this would be self explanatory when I got into the software but the only setting that I can find is one that gives me the option to print from either the left or the right head. Nothing that allows printing from both heads nor any options. Can anyone help with this? I was thinking that this is probably something real easy that I am overlooking or something. Any help would be great. Thanks.