Baird Meter Hose CFM

[wyaple]

For those who have Baird meters or are just curious as to what those performance markings mean (generic 1-10 scale), I have measured the airflow (using the included reducer for the typical vacuum hose size) and am posting the results. This inexpensive gauge (about $30), does a fairly good job of measuring differences in airflow for vacuum cleaners. As the graph shows, the response is even fairly linear, except for Baird level “10”. For that data point, I’m wondering if the spring that holds the yellow disk is getting a bit stretched out.

When the gauge just barely moves the disk, the unlabeled “zero” mark is about 46 CFM. If whatever you’re testing can’t move the Baird meter off the yellow disk’s resting place, you’ve got a very poor vacuum (leaky hose, etc.) If you have a hose that pegs the meter at the “10” mark (with or without a snapping sound), you have phenomenal or even excessive airflow. You may even have various floor tools “stick” to the floor and be difficult to move with this much power.

Generally speaking most bagless vacs, including older Dysons and Rainbows, score around a 3 to 4 (69 to 77 CFM) from the hose end while many bagged vacs (upright or cylinder) score around a 6 to 8 (93 to 104 CFM) with empty bags. Yes, as the bags fill up, you do lose airflow but as I’ve posted previously, if using a HEPA cloth bag, not much is lost.

Out of my slowly growing collection, the best hose airflow comes from any Kirby (about a 9) and my el cheapo Hoover Tempo Widepath (about a 9.5).

Enjoy! And feel free to comment and even post your Baird meter results.

Bill

 

[sptyks]

Bill,


Thank you for posting these Baird meter results. I use my Baird all the time to help me determine when to change the bag on all my Kirby's that use disposable bags.

 

[charleskirby66]

WOW! Thank you so much for posting these results, and for producing such an easy-to-read graphic. You rock! I've been wondering what those whole number values represented on the Baird.

Now if I could figure out what the cylindrical spoke with metal springs around its head is used for, I'll be all set! It looks like the torch the Statue of Liberty is holding, and for the life of me, I can't figure out what that is or how it is used.

 

[wyaple]

I wondered that too until...

I plugged it into the Kirby's exhaust port (filltube). It measures exhaust airflow from my '87 Heritage to my newest G6 perfectly. By the way, since you're measuring exhaust airflow, the scale is different. A "10" reading is somewhere in the 140 CFM range.

Bill

 

[charleskirby66]

Thanks Wyaple

Wow! I can't wait to try it now. I knew it had to have a use, I just couldn't figure it out. So, do you stick the long, tapered end into the fill tube and then afix the Baird meter onto the other end? Do you screw-off the black "cap"? Just trying to figure it out.

 

[wyaple]

Pics of Measuring Kirby Exhaust Airflow

Hope this helps. Let me know what readings you get...

Bill

 

[tolivac]

Interesting idea to use the Baird guage to test exhaust,too!That man is a genius!

 

[charleskirby66]

Brilliant, Wyaple!

Thank you SO much! I didn't get a chance to do this because I got home from rehearsal late. Hopefully tonight, if they don't keep us in dance rehearsal too long!

 

[wyaple]

Updated Baird Hose Results

Since I recently acquired a more powerful machine (Sentria II), I was able to make more accurate measurements of the last two gauge markings, namely the "9" and "10". The results are more in line with what I suspected, the spring is getting a bit over-stretched and reports somewhat non-linear results. BUT, now the graph looks much smoother. For those making heavy, repeated use of this meter, remember that the inside will collect fine dust that will eventually skew the readings. Take a clean (preferably microfiber) cloth and clean out the inside periodically.

Incidentally, my new Sentria II can pull 120 CFM from the hose with no bag and 118 CFM from the hose with the Kirby white HEPA cloth bag. It is the first vac I have that can completely max out the Baird meter at the hose end with a bag installed. Great for above the floor cleaning. What a monster!

Enjoy!

Bill