Inlet/Outlet Sizing questions

[cruizin31]

Apologies if this has been asked before. I have an older 2 hp Griz spinning a 12 inch impeller and a 5 inch inlet. If I plumb the
top hat with 5 inches to the collector and a 6 inch inlet from the machines, will this setup work? My runs are quite short and only 1 machine
is running at a time. I'm trying to figure this out before pulling the trigger on the ducting.

[juicegoose]

Any design is only as good as the weakest part. The 5" run will be the deciding factor. I would say if possible change the 5" inlet to a 6" inlet. It's easily done with a jigsaw.dremel tool and a HVAC fitting.

[cruizin31]

Thanks, Juice. Even with that mod the question still remains, will a 12 inch impeller flow adequate cfm to support 6 inch ducting to the machines.

[juicegoose]

sorry I didn't get back with you. There is a nice guy within the forum that recently duct his entier setup with 6" and says it works great. I can tell you from personal experience that with a 10'-5" section of flex house hooked up to my 50-760 the dust movement in the collection bag was just okay. Now after I upgraded to a 6" opening and put a 10'-6" piece of flex the bag ressembles a freakin snow globe. It's amazing how much more air it seems to be pulling.

The answer to your question isn't super easy. Sure your setup will work with 6" ducting if you design it right. A poor duct design can kill CFM quicker then a underpowered collector will. Keep blast gates as close to the main trunk as possible and keep hoses as large as possible until you have to reduce them and your collector will be fine.