u tube mod on MR-1
u tube mod on MR-1
i tried the u tube mod on my MR-1 and wanted to share my experience. it's a much smaller box than the MR-2, and presented some problems. it's being driven by a PCX-40.
the bulkhead for the becket is the same size as the larger units, so 1 1/2" fittings are still what you need. it's obviously located the same distance from the wall of the chamber since the fitting holds on by itself once you get it over the bulkhead.
due to the location of the drain fittings, there is not enough room in the chamber to accomodate two slip x slip 1 1/2" 90's. if you use a street elbow off the bulkhead, you can just make it all fit, but the output is not centered in the skimming tower. this creates a lot of turbulence in the foam head. i also tried using a 45 fitting in place of the 90 to direct the becket output into the tower, this creates a different type of turbulence which appears to be a little more controllable. both configurations pretty much eliminate the microbubbles from the drain.
once the u tube is in place, you can only open the air valve a short way, maybe 1/2 turn max, before overflowing the skimmer. right now i'm running it with the 90 street elbow + 90 elbow, only about 1/4 turn of air, with the water level in the tower just at the bottom of the injector . it's giving a good dry foam, but i don't really have a lot of control with only 1/4 turn being the difference between dry skimming and overflowing.
if anyone has any suggestions about what to try next, i'd love to hear them. should i raise the becket, to get the effect of lowering the water level relative to the becket but still have enough water in the tower to get skimmate? should i get an extension for the tower, so i can jam more foam up there? or maybe just restrict the air intake so i have more control over the low range that it requires now?