Hello,There is a small problem with aqua jet cutting. It is difficult to explain for me as a Dutchman in English but a water jet (even with abrasive additives) tends to act as a bullit. At the entrance it cuts a small hole, at the other end there is a "big" gab. Cutting thin materials is no problem but as soon as it gets thicker the jet makes a connical hole. When you cut a round viewport you will end up with a slightly connical one. This requires machining afterwards to meet the neccessary tolerances.Regards,Thijs Struijs