CFM, LIFT AND WAND SIZE

[tman7]

I know this topic has been talked about plenty on this board.

I read in a previous post that lift is largely the same at the wand for just about any hose, wand size configuration, but I would be interested in knowing is there really that much more cfm gained by using a 2 in tubed wand vs a 1.5 or 1.75, assuming were talking about glided wands.

Thanks for your thoughts

 

[Larry Cobb]

tman;

I'll jump in.

The wand tube CFM difference between 1.75" & 2" is about the same difference as about 3 feet more of 2" vac hose.

Insignificant.

The wand head design is much more important in extraction efficiency. That's the difference that most cleaners notice.

Look for a design that has good flow at the edges. Generally, this means the slot comes straight up into a vac chamber. The vac chamber should smoothly flow into the next chamber which feeds into the wand tube itself. This connection should be free of sharp edges.

Finally, the tube should be attached to the head at two different places for strength at the connection.

Larry Cobb

 

[AzCleaner]

I'm glad you brought this up because I didn't want to ask even more questions Great explanation though. I do have a question (weird I know). Anyway, when you say the difference is maybe 3CFM between a 1 1/2" and 2" hose. Is that per foot of hose? If so, I would think that the difference would be fairly significant once you start to run 100' - 150' of hose.

 

[tman7]

I think what cobb is saying is that the loss of cfm going from a 2 in tube to a 1.75 in tube is equivalent to adding 3 ft of 2 in hose to a run of vac hose. Practically none.