The Cheerios contest?

[cgallery]

I'm going to propose a little contest. Not between the members here, but rather their dust collectors/shop-vacs. This contest is intended to teach and inform. PLEASE, NO WAGERING!

The question that got this started was someone asking, in another thread, how well a shop vac would work compared to a dust collector for collection on a BT3K.

We all know that shop vacs excel at pressure, and dust collectors at volume. Is a 2.25" port too restrictive for a dust collector? I've recently read about some guys using their dust collectors on 1" tool ports!

I have consulted with NIST and they have approved the following test. Lay your collection hose on the floor or bench, and turn the device on. Place a Cheerio on the floor and start scooting it towards the hose with your finger (NIST suggests the pointing finger), until the hose sucks the Cheerio along the floor and into the system.

Now, how close (in inches) to the inlet do you have to get before the collector/vac does the rest? Try this test several times to get an average and post back here with: (1) Make/model of device (i.e., Shop-Vac 12-gallon), (2) Average inches before inhaling. (3) Any other pertinent information.

Of course, I'm out of Cheerios, but I'll get some more tomorrow and post my the results.

Extra credit would be trying even smaller tool ports. And different length hose runs.

It would also be interesting to see how Fein and Festool and PC vacs compare to Shop-Vacs and Rigids, etc.

If you have a dust collector make sure you use a 2.25" reducer. If you want to let us know how far it worked with larger diameter inlets that is fine, but the 2.25" information is the reason for the test to begin with.

My prediction: The smallest (non-portable) dust collector will out-inhale (distance-wise) any shop-vac by 2:1. But it is just a guess.

[sbs]

Sounds completely unscientific and irrelevant to dust collecting ability.

But fun. I'm in. Off to steal the wife's cheerios...

Oh, but she buys the store-brand cheerios. We'll need to add measurements of average mass and coefficient of friction between cereal and floor for the various varieties of Os and floors to the data requirements. Anybody got a _really_ small spring scale?

[crokett]

sbs raises some excellent points. Here are a few others. Are they actual Cheerios or an off-brand? My wife buys the off-brand that is a bigger piece of cereal. What surface are we sucking them from? I'd imagine the cereal will move sooner on my laminte floor-topped bench than my concrete floor or a plywood floor. These are all questions that must be answered.

[Thom2]

before or after I put the milk on them????




I've got a 4x8 piece of laminated particle board set up as a temporary workbench right now, before I take it down, I may just have to try this.

[cgallery]

Alright guys, these are indeed good questions.

Cheerios are preferred. Generics are okay as long as you specify that they are generics. Any flat, level surface is fine, but tell us what you used so if the #'s start coming in strange we can try to figure out contributing factors.

The trick is to avoid getting caught up in the details. If we need to, we can test again. Let's just get the Cheerios rolling.

[cgallery]

before or after I put the milk on them????




I've got a 4x8 piece of laminated particle board set up as a temporary workbench right now, before I take it down, I may just have to try this.

Warning: While using milk isn't an immediate disqualification, it certainly may contribute to an almost unexplainable odor in your dust collector bags about two days after conducting the test.

[TheRic]

To keep things a little more constant. We could all do the test on the same type of wood, sanded the same. For example Pine plank sanded with 200 grit. OSB has a rough and smooth side, and I have seen those vary from brand. So if OSB is used it should be sanded the same. MDF (unpainted), I would THINK they would have the same friction (close enough for this experiment) without having to be sanded.

[LCHIEN]

Alright guys, these are indeed good questions.

Cheerios are preferred. Generics are okay as long as you specify that they are generics. Any flat, level surface is fine, but tell us what you used so if the #'s start coming in strange we can try to figure out contributing factors.

The trick is to avoid getting caught up in the details. If we need to, we can test again. Let's just get the Cheerios rolling.

I think for the sake of experimental consistency that the surface be something easily reproducible and available to most all. Rather than "any flat level surface". I would suggest a piece of reasonably well planed whitewood pine (such as Lowes or HD sells as 1x4 stock). reasonably well planed means flat and free of surface defects an knots and a good smooth example of what you should expect from a store finish.


Ric's suggestion of sanding this surface with 200 grit sandpaper is great.

Suck along the grain direction and it won't really matter if its a 1x4 or wider. The board should be placed on a level surface to the eyeball - a couple of degrees won't make a big difference.

FInally, there's some discussion whether the length of 2.5" piping before a larger diameter (a reducer + 2-3 feet of 2.5" hose or pipe compared to just a reducer at the end of a 4" hose). makes a difference. A long pipe may lead to more restriction but it may also lead to more "organized" coherent airflow (or am I thinkiing about collimating fiber optic lenses here?).
If I set this experiment up I will have to try both ways!

[Stytooner]

This ain't cheerios, but I did do some testing a few years ago with my home made DC. Once we get past the itsy bitsy cheerio test, perhaps I could interest you in a test that may be a little more challenging.





At any rate, some of you have seen these test results before and can verify that these following photo's were real and unretouched by human hands.







Here are my results for those that haven't seen them before. It is a series of time lapsed photo's. You be the judge as to whether your shop vac can preform as well.












































Not altogether untouched by software manipulation however.

[cgallery]

I think for the sake of experimental consistency that the surface be something easily reproducible and available to most all. Rather than "any flat level surface". I would suggest a piece of reasonably well planed whitewood pine (such as Lowes or HD sells as 1x4 stock). reasonably well planed means flat and free of surface defects an knots and a good smooth example of what you should expect from a store finish.


Ric's suggestion of sanding this surface with 200 grit sandpaper is great.

Suck along the grain direction and it won't really matter if its a 1x4 or wider. The board should be placed on a level surface to the eyeball - a couple of degrees won't make a big difference.

Okay, I'll agree. So we're amending the test so we use a piece of pine at least 3.5" wide and sanded to 200-grit, placed on a level surface.

For the sake of consistency, the inlet should rest on TOP of the test board, rather than on the same surface that the test board sits on.

[Stormbringer]

Two questions/comments:

1) Regarding the difference in surface area. Can that variable be removed if the hose is held from above, and the distance from the ground at which the Cheerio is inhaled, is the determining factor? ie. dust collector pulled cheerios from 14" while shop vac sucked them up at 8". This would remove the questionable smoothness of the surface area from the equation, no? Simply support hose end and measuring stick in the same hand, make mark on the stick if not ruled, and report findings. Just a suggestion.

2) Does it matter if the 4" to 2.5" reducer is placed at the dust collector inlet or 15ft away at the end of the 4" hose run?


Greg

EDIT: Sorry, didn't see the sanded surface area suggestion prior to posting.

[cgallery]

Two questions/comments:

1) Regarding the difference in surface area. Can that variable be removed if the hose is held from above, and the distance from the ground at which the Cheerio is inhaled, is the determining factor? ie. dust collector pulled cheerios from 14" while shop vac sucked them up at 8". This would remove the questionable smoothness of the surface area from the equation, no? Simply support hose end and measuring stick in the same hand, make mark on the stick if not ruled, and report findings. Just a suggestion.

2) Does it matter if the 4" to 2.5" reducer is placed at the dust collector inlet or 15ft away at the end of the 4" hose run?


Greg

EDIT: Sorry, didn't see the sanded surface area suggestion prior to posting.

I thought about #1, but concluded that it would be much more difficult to "lift" the Cheerio than to pull it. So I concluded that the results may be less radical, and harder to compare.

On #2, I think most people put their reducers at the tool rather than the dust collector (let me know if I'm wrong). Performing the test in the same way the tool is used is the most logical, so reducer should go at the end of the run, not at the collector.

[cgallery]

One more idea. Seeing as we're using uniform boards, we may want to place the Cheerio 1" from one end, and then advance the hose from the other end. Once the Cheerio gets sucked in, stop and measure from the current hose location to where the Cheerio started.

[TheRic]

....On #2, I think most people put their reducers at the tool rather than the dust collector (let me know if I'm wrong). Performing the test in the same way the tool is used is the most logical, so reducer should go at the end of the run, not at the collector.

I think Loring is correct that the long length of reduced hose might actually improve the air flow. The air would get a chance to be organized (not a good choice of words but can't think of better at the moment ).
If possible try both ways. Overall length will be a major factor no mater which way it is done.

[cgallery]

If possible try both ways. Overall length will be a major factor no mater which way it is done.

Exactly. It won't take long and Cheerios are cheap (and if you have a separator you can even put them back in the box when you're done--just kidding). Just let us know the results and how you got 'em. If you think to try a different way, just post the changes you made and the new results.