Larger diameter wand more lift?

[gimmeagig]

Hi,
In a previous thread I was made aware of the possibility that my 1.5" 2 jet wand (with a slot/hole glide)was not that great, so I bought a used Prochem Quad wand ( with a hole pattern only glide) from a friend on this forum and I am amazed at the difference. My inline filter for my vacuum line going back to the truck really gets loaded up lately, even though I pre vacuum very thoroughly every time. So I know that the new wand must be more efficient. I just don't understand what is actually physically happening there. The diameter of the wand tube is 1.75" so that is not that much larger than the previous one but there is a very noticeable difference. Or can the number of jets have something to do with the good results. If I got a 2" wand would that give me even greater power or are there other factors at play here?

 

[roro]

Hi,
The diameter of the wand tube is 1.75" so that is not that much larger than the previous one but there is a very noticeable difference.?

The 1/4" increase in size seems small but it is approx 35% theoretically allowing more air to flow. Going to 2" is an additional 30% approx.

roro

 

[Ryan Allen]

It's a matter of surface area > void. In a larger diameter wand, there is less surface area (i.e. the inside surface of the wand) compared to the airspace (void) inside the wand. In a smaller wand you have a much smaller void, but only slightly less surface inside the wand. It takes more pressure to overcome the friction and gravity of the smaller airspace. So, generally speaking, the greater the surface to void ratio (the more airspace you have inside the surface) the more efficient the pressure of your extractor will be, allowing greater extraction rates with larger diameter wands.

 

[lance]

A smaller diameter wand increases lift (think of it as resistance) and, since lift and air flow are inversely perportional to each other, the cfm's at the wand are decreased.

What matters also, though very hard to see, is the design of the wand head and what is going on at the wand/carpet interface. The Prochem quad jet and TI wand are not only built very well they are designed very well also. That makes a big difference in the recovery of the dirty water.

When someone says or thinks that the wand they use doesn't matter, remind them that it is the only connection between the TM and the carpet. Why then would you want an inferior tool that you use everyday if your goal is to achieve great results (and time savings also.)