wyaple
Well-known member
All,
When I put my 70's Convertible (U4007) on my airflow box, I measured several things. Take a look at what I found:
1) With the brush roll off, installing a "C" bag reduced the airflow by 8.7 CFM
2) With the brush roll on, bag or no bag didn't change the airflow at all.
3) Installing a belt and having the brush roll spinning reduced the airflow by 18 CFM.
The spinning brush roll uses much more CFM via motor drag than a bag, hence you could fill a bag partway and NOT ACTUALLY LOSE ANY AIRFLOW!
GULP!
How many bagged vacs can say that? I'm guessing (and it's a complete guess until I finish testing) that a cloth Hoover "Q" bag might be filled up halfway before any airflow is lost. This is Earth-shattering news to me! A bagged vacuum that doesn't lose CFM for a significant period of time? Even Kirbys with giant HEPA bags can't claim that.
Bill
When I put my 70's Convertible (U4007) on my airflow box, I measured several things. Take a look at what I found:
1) With the brush roll off, installing a "C" bag reduced the airflow by 8.7 CFM
2) With the brush roll on, bag or no bag didn't change the airflow at all.
3) Installing a belt and having the brush roll spinning reduced the airflow by 18 CFM.
The spinning brush roll uses much more CFM via motor drag than a bag, hence you could fill a bag partway and NOT ACTUALLY LOSE ANY AIRFLOW!
GULP!
How many bagged vacs can say that? I'm guessing (and it's a complete guess until I finish testing) that a cloth Hoover "Q" bag might be filled up halfway before any airflow is lost. This is Earth-shattering news to me! A bagged vacuum that doesn't lose CFM for a significant period of time? Even Kirbys with giant HEPA bags can't claim that.
Bill
