Pics at bottom........Head adapter is done and bench is fully underway. Some small issues will have to be looked at once the bench is calibrated. There is some turbulence with the depression control which moves the verticle collumn a little. It's somewhere in the 1/2 " range is how much it moves. The head adapter was pretty simple to make. The base is the 3/4 melamite along with the two sides. The hole is small enough to let the acrilic tube (6"x 4.125 id) to sit on it and make a seal. A piece of mdf with a hole big enough for the tube to sit inside it is on top of the melamite base and the sides screw into both with "L" brackets. The top is a piece of 3/4" aluminum with a 4.5" hole in it. The tube has a groove machined into the top where it fits inside the aluminum. Duct seal from my electrical stock is cramed around the tube and into the groove. The top is pressed onto the tube to make everything flush. Then all I had to do is glue on a gasket and cut the hole out.
The wet flow recovery is working out pretty good. No liquid is getting into the main cabinet. I will know later in the future if the fluid is making its way to the second chamber in the box. So far I feel it's not if it is not getting into the measuring chambers. I fed in one test session about 20 ounces and most came out. There is some sitting on the sloped part. Not enough pitch for the little left.
There is sometimes a buzz inside the machine. Can it be the plate for the orifice s? It is reinforced. Like I said only once in a while. So far testing can only be done at 10" Seem to only get to 200 at 16 and thats it. This is with 4 shop vac motors in my box. If I stayed at 10 inches, it looks like I can test a head up to 200 to 230 cfm. Then convert. Only thing is knowing how at higher depressions the port can change. All in all, so far so good.