Toilet Roll Tube Testing Results

I've seen a few paper towel and toilet roll tube testing videos on YouTube and have found some people put great faith in them. So I grabbed a Kirby G5 and G6 and got down to testing what the seemingly "magic" rolling tube can actually uncover.

Testing conditions:

1) Both machines, which normally have HEPA cloth bags, had the bags removed and outer bags zipped up. By the way, before anyone complains about that, my anemometer says that a fresh Kirby HEPA bag only restricts airflow a whopping 2 CFM. So no big deal.

2) Both machines were plugged into a power strip that was plugged directly into a dedicated 20 Amp (2400 Watt) outlet. This was done to ensure exactly the same voltage going to the test subjects. This is a very important step as varying voltages definitely affect the outcome.

3) Both machines had their brush rolls spinning and heights adjusted all the way up and were checked to be at the same height within about 1/32nd of an inch. If the heights were misadjusted (say 1 click), the results usually favored the lower machine.

4) Tests were performed a minimum of 20 times on both medium pile carpet and bare flooring (concrete).

5) The toilet roll tube was placed in three locations; the middle and both ends of the nozzles.

6) Both machines had the same brush roll (152502 oblique loose tufts) and belt installed and were of equal age (new). I realize that belts and brush rolls for this test shouldn't make any appreciable difference as they never touched any surface.

7) I knew beforehand that the G5 had 126 CFM and the G6 had 122 CFM as previously measured on my airflow box.

Medium Pile Carpet Results:
In every instance, the paper tube was either "stuck" or could be "re-stuck" to the G5's nozzle. The 4 CFM difference was readily apparent.

Bare Floor (Concrete) Results:
About 75% of the time, the G5 won, about 25% of the time, the G6 won.

CONCLUSION:
Since a paper tube is VERY light, it can detect VERY small differences in airflow, even becoming finicky on bare floors. The G5 and G6 only have a 4 CFM difference in airflow and that difference only amounts to a little over 3%, which is barely statistically significant. Hence, people claiming massive superiority by performing this type of test could easily be fooling themselves if they pair up two machines with very small airflow differences.

RECOMMENDATION:
Stick to real, measurable airflow/airbox measurements if you care about such things.

Further testing may be done if time permits pairing up my G4 and G6 because they differ only by 2 CFM instead of 4 CFM.

Bill

Photos... < > Photo 1 of 3 View Full Size


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Post# 369353 3/27/2017 at 19:20 (2,579 days old) by wyaple (Pickerington, OH)
Checkrate/Likes 1 I've seen a few paper towel and toilet roll tube testing videos on YouTube and have found some people put great faith in them. So I grabbed a Kirby G5 and G6 and got down to testing what the seemingly "magic" rolling tube can actually uncover. Testing conditions: 1) Both machines, which normally have HEPA cloth bags, had the bags removed and outer bags zipped up. By the way, before anyone complains about that, my anemometer says that a fresh Kirby HEPA bag only restricts airflow a whopping 2 CFM. So no big deal. 2) Both machines were plugged into a power strip that was plugged directly into a dedicated 20 Amp (2400 Watt) outlet. This was done to ensure exactly the same voltage going to the test subjects. This is a very important step as varying voltages definitely affect the outcome. 3) Both machines had their brush rolls spinning and heights adjusted all the way up and were checked to be at the same height within about 1/32nd of an inch. If the heights were misadjusted (say 1 click), the results usually favored the lower machine. 4) Tests were performed a minimum of 20 times on both medium pile carpet and bare flooring (concrete). 5) The toilet roll tube was placed in three locations; the middle and both ends of the nozzles. 6) Both machines had the same brush roll (152502 oblique loose tufts) and belt installed and were of equal age (new). I realize that belts and brush rolls for this test shouldn't make any appreciable difference as they never touched any surface. 7) I knew beforehand that the G5 had 126 CFM and the G6 had 122 CFM as previously measured on my airflow box. Medium Pile Carpet Results: In every instance, the paper tube was either "stuck" or could be "re-stuck" to the G5's nozzle. The 4 CFM difference was readily apparent. Bare Floor (Concrete) Results: About 75% of the time, the G5 won, about 25% of the time, the G6 won. CONCLUSION: Since a paper tube is VERY light, it can detect VERY small differences in airflow, even becoming finicky on bare floors. The G5 and G6 only have a 4 CFM difference in airflow and that difference only amounts to a little over 3%, which is barely statistically significant. Hence, people claiming massive superiority by performing this type of test could easily be fooling themselves if they pair up two machines with very small airflow differences. RECOMMENDATION: Stick to real, measurable airflow/airbox measurements if you care about such things. Further testing may be done if time permits pairing up my G4 and G6 because they differ only by 2 CFM instead of 4 CFM. Bill Photos... < > Photo 1 of 3 View Full Size

Post# 369373 , Reply# 1 3/27/2017 at 23:27 (2,579 days old) by pr-21 (Middletown, OH)
Checkrate/Likes When the Gsix came out, the cloth outer bag was made for hepa filtration (thicker), plus they had paper hepa bags to go in it, which would account for the G5 winning. Don't get me wrong, the G5 is my favorite of all the G series. They corrected this when the G7 came out as the outer bags were designed for better air flow. And of course this all changed again, when Kirby introduced the cloth inner hepa bags. It would be interesting if you did the same test and swapped the outer bags on these two Kirby's and see if the results were the same or different..... Sincerely, PR-21 Bud

Post# 369380 , Reply# 2 3/28/2017 at 02:21 (2,579 days old) by sebo4me (Cardiff)
Checkrate/Likes Well done Bill. Very interesting information! :)

Post# 369705 , Reply# 3 3/31/2017 at 22:25 (2,575 days old) by wyaple (Pickerington, OH)
Checkrate/Likes *Toilet Roll Tube Testing Results #2* Continuing on to see if the infamous toilet paper tube roll can detect as little as a 2 CFM difference, I have pitted a G4 with 124 CFM against a G6 with 122 CFM. The tests were run as stated in post #1, with the exception of the brush rolls being different. The G4 has the older chevron style and the G6 has the newer oblique style. Medium Pile Carpet Results: More than 90% of the time, the paper tube was either "stuck" or could be "re-stuck" to the G4's nozzle. The 2 CFM difference was fairly apparent. Bare Floor (Concrete) Results: Mostly the G4 won overall, but only when the tube was either in the middle or right (non-lighted) side. The G6 won mostly when the tube was located on its right (lighted) side. CONCLUSION: Since a paper tube is VERY light, it can detect VERY small differences in airflow. The G4 and G6 only have a 2 CFM difference in airflow and that difference only amounts to a little less than 2%, which isn't statistically significant. Hence, people claiming massive superiority by performing this type of test could easily be fooling themselves if they pair up two machines with very small airflow differences. RECOMMENDATION: Stick to real, measurable airflow/airbox measurements if you care about such things. Bill Photos... < > Photo 1 of 4 View Full Size

Post# 369709 , Reply# 4 3/31/2017 at 22:52 (2,575 days old) by panasonicvac (Northern Utah)
Checkrate/Likes The G4 would've dominated the G6 if it had a metal fan in it.

Post# 369735 , Reply# 5 4/1/2017 at 12:48 (2,575 days old) by sptyks (Skowhegan, Maine)
Checkrate/Likes Bill, It's probably not possible, but it would be very interesting to do the Baird and toilet paper roll airflow tests between 2 identical Kirby's except one will have the standard white 11 blade Amodel fan in it and the other one would have the older 10 blade metal fan in it. ~Stan

Post# 369748 , Reply# 6 4/1/2017 at 18:41 (2,574 days old) by wyaple (Pickerington, OH)
Checkrate/Likes *Stan,* As far as I'm aware of, isn't the Amodel fan the very one Kirby had NASA design for a few million? Would Kirby actually pay that huge sum for a fan that produces fewer CFM than an old metal fan? I don't have any Kirbys with a metal fan as the oldest one in my collection is a 1987 Heritage II Legend. Bill

Post# 369760 , Reply# 7 4/1/2017 at 21:02 (2,574 days old) by sptyks (Skowhegan, Maine)
Checkrate/Likes *Bill* You are correct, The Amodel fan was designed by NASA for Kirby. I agree with you that the new fan should provide at least as much airflow as the metal fan. Believe it or not, the Amodel fan is 300% - 400% stronger than the metal fan: spinoff.nasa.gov/spinoff1997/ch9.... However, there are several people here on Vacuumland that are of the opinion that the old metal fan provides much more airflow than the new Amodel fan. That's why I thought the toilet paper tube would be a good test to see who's right. This post was last edited 04/01/2017 at 21:32