[fireant911]

Thanks island911 & 908/930! In regards to actual usage, this probably isn't the best method to test my designs BUT it is the easiest since I can tweak and existing design and reinstall it in the tree in a relatively short amount of time. I had read about the 'acetone smoothing' which would most likely help seal the part but, I think, that is for ABS material and I am using the standard PLA material.

Yes, I concur, those half cartridges are neat and have many applications! I will continue testing and see if my current design leaks - I can rig up something to do some 'air under water' testing and see how much pressure is required to see bubbles.

I certainly appreciate your input here - thanks again!