Rate of Air Flow vs Volume of Air Flow

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dusty
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Re: Rate of Air Flow vs Volume of Air Flow

Post by dusty »

Testing resumed but only momentarily. My kludge coupler works but will not survive multiple applications, The foam seal collapses. Back to the drawing board.

However, I was able to do some testing and do not believe the results to be encouraging. With with two ports closed the airspeed is continuously above the meter spec (5905ft/min). With the second and third ports open the airspeed drops to 4500s and 3800s respectively. I hoped for those readings to remain above meter specs.

More work required on the coupler seal.

Don't panic over the poor numbers. They are not yet verifiable.
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RFGuy
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Re: Rate of Air Flow vs Volume of Air Flow

Post by RFGuy »

dusty wrote: Thu Dec 01, 2022 10:21 am Testing resumed but only momentarily. My kludge coupler works but will not survive multiple applications, The foam seal collapses. Back to the drawing board.

However, I was able to do some testing and do not believe the results to be encouraging. With with two ports closed the airspeed is continuously above the meter spec (5905ft/min). With the second and third ports open the airspeed drops to 4500s and 3800s respectively. I hoped for those readings to remain above meter specs.

More work required on the coupler seal.

Don't panic over the poor numbers. They are not yet verifiable.
Dusty,

I still think this is an improvement over what I have been seeing with my original DC-3300. I have tabulated the numbers for comparison below. Also corrected the airflow numbers for what I reported before to now calculate it in the 2.5" aperture it was measured in (as the discussion converged to above). I know you didn't give me exact numbers for the 2 and 3 ports open case, but when you get better numbers here I can update what is below. Using this for now, what I see is that when I go from 1 port open to 2 ports open that I see a 31% drop in airflow. Going from 1 port open to 3 ports open, I see a 48% drop in airflow. However, for your upgraded DC-3300, going from 1 port open to 2 ports open results in a 24% drop in airflow. When you go from 1 port open to 3 ports open it drops 36%. That is still a significant improvement in performance over the original DC-3300. IF you can get a better seal again, your numbers may actually go up even more for the 2/3 ports open case. I was expecting a bit better performance out of the DC-3300 upgrade, based on the comments that Jim made about it. However, in your case you may be losing some airflow potentially due to using the 12" filter hood. In any event, I think we have confirmed that the DC-3300 upgrade/DC-6000 is an improvement on the original DC-3300 and that is a good thing. However, those who thought this upgrade performance would be night and day difference from the original are a bit off the mark IMHO. It is an incremental improvement. Intuitively, I think your results and my results make perfect sense. We should expect a drop in airflow/port when more than one port is opened on that 3 port manifold. I don't think we will ever see the same airflow out of the 1 port open case when compared to all 3 ports open on the 3 port manifold. Rather what is important is whether you can get sufficient airflow to not have dust settle out in either a vertical/horizontal duct/hose configuration. In the worst case with 3 ports open you still have almost 4000 fpm which means yours conceivably could provide dust collection to multiple woodworking tools through 2-1/2" hoses without any issues (3000 fpm minimum needed for horizontal runs and 4000 fpm minimum needed for vertical runs). I don't believe this has ever been the case for the original DC-3300 with multiple ports open though. Lastly, thanks for all of your efforts here and for purchasing an anemometer for measuring your DC-3300 upgrade. It is appreciated and very useful information IMHO.

P.S. Just wanted to point out again that the original DC-3300 was spec'ed as a 0.5HP dust collector with a motor that draws 8A and has a 4 blade fan impeller. The DC-3300 upgrade/DC-6000 is listed as a 1.5HP dust collector with a motor that draws 8A and has a new 6 blade fan impeller. I think we can agree that the DC-3300 upgrade motor likely spins no faster than the original DC-3300 motor because both only draw 8A. Likely the key difference with the upgrade is the new and improved fan impeller design, which is why the upgrade is an incremental improvement and not a revolutionary improvement, in my opinion.

AIRSPEED - <measured>
1 port open at a time: (units=ft/min)
RFGuy: 4944 Dusty: 5905*

2 ports open at a time: (units=ft/min)
RFGuy: 3411 Dusty: 4500*

3 ports open at a time: (units=ft/min)
RFGuy: 2584 Dusty: 3800*


AIRFLOW - <calculated>
1 port open at a time: (units=CFM)
RFGuy: 168.5 Dusty: 201.3*

2 ports open at a time: (units=CFM)
RFGuy: 116.3 Dusty: 153.4*

3 ports open at a time: (units=CFM)
RFGuy: 88.1 Dusty: 129.5*


NOTE: * indicates measurement could very well be higher than shown, but this is the best, max reading taken so far
AirflowComparison.jpg
AirflowComparison.jpg (39.44 KiB) Viewed 1300 times
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dusty
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Re: Rate of Air Flow vs Volume of Air Flow

Post by dusty »

RFGuy wrote: Thu Dec 01, 2022 10:51 am
dusty wrote: Thu Dec 01, 2022 10:21 am Testing resumed but only momentarily. My kludge coupler works but will not survive multiple applications, The foam seal collapses. Back to the drawing board.

However, I was able to do some testing and do not believe the results to be encouraging. With with two ports closed the airspeed is continuously above the meter spec (5905ft/min). With the second and third ports open the airspeed drops to 4500s and 3800s respectively. I hoped for those readings to remain above meter specs.

More work required on the coupler seal.

Don't panic over the poor numbers. They are not yet verifiable.
Dusty,

I still think this is an improvement over what I have been seeing with my original DC-3300. I have tabulated the numbers for comparison below. Also corrected the airflow numbers for what I reported before to now calculate it in the 2.5" aperture it was measured in (as the discussion converged to above). I know you didn't give me exact numbers for the 2 and 3 ports open case, but when you get better numbers here I can update what is below. Using this for now, what I see is that when I go from 1 port open to 2 ports open that I see a 31% drop in airflow. Going from 1 port open to 3 ports open, I see a 48% drop in airflow. However, for your upgraded DC-3300, going from 1 port open to 2 ports open results in a 24% drop in airflow. When you go from 1 port open to 3 ports open it drops 36%. That is still a significant improvement in performance over the original DC-3300. IF you can get a better seal again, your numbers may actually go up even more for the 2/3 ports open case. I was expecting a bit better performance out of the DC-3300 upgrade, based on the comments that Jim made about it. However, in your case you may be losing some airflow potentially due to using the 12" filter hood. In any event, I think we have confirmed that the DC-3300 upgrade/DC-6000 is an improvement on the original DC-3300 and that is a good thing. However, those who thought this upgrade performance would be night and day difference from the original are a bit off the mark IMHO. It is an incremental improvement. Intuitively, I think your results and my results make perfect sense. We should expect a drop in airflow/port when more than one port is opened on that 3 port manifold. I don't think we will ever see the same airflow out of the 1 port open case when compared to all 3 ports open on the 3 port manifold. Rather what is important is whether you can get sufficient airflow to not have dust settle out in either a vertical/horizontal duct/hose configuration. In the worst case with 3 ports open you still have almost 4000 fpm which means yours conceivably could provide dust collection to multiple woodworking tools through 2-1/2" hoses without any issues (3000 fpm minimum needed for horizontal runs and 4000 fpm minimum needed for vertical runs). I don't believe this has ever been the case for the original DC-3300 with multiple ports open though. Lastly, thanks for all of your efforts here and for purchasing an anemometer for measuring your DC-3300 upgrade. It is appreciated and very useful information IMHO.

P.S. Just wanted to point out again that the original DC-3300 was spec'ed as a 0.5HP dust collector with a motor that draws 8A and has a 4 blade fan impeller. The DC-3300 upgrade/DC-6000 is listed as a 1.5HP dust collector with a motor that draws 8A and has a new 6 blade fan impeller. I think we can agree that the DC-3300 upgrade motor likely spins no faster than the original DC-3300 motor because both only draw 8A. Likely the key difference with the upgrade is the new and improved fan impeller design, which is why the upgrade is an incremental improvement and not a revolutionary improvement, in my opinion.

AIRSPEED - <measured>
1 port open at a time: (units=ft/min)
RFGuy: 4944 Dusty: 5905*

2 ports open at a time: (units=ft/min)
RFGuy: 3411 Dusty: 4500*

3 ports open at a time: (units=ft/min)
RFGuy: 2584 Dusty: 3800*


AIRFLOW - <calculated>
1 port open at a time: (units=CFM)
RFGuy: 168.5 Dusty: 201.3*

2 ports open at a time: (units=CFM)
RFGuy: 116.3 Dusty: 153.4*

3 ports open at a time: (units=CFM)
RFGuy: 88.1 Dusty: 129.5*


NOTE: * indicates measurement could very well be higher than shown, but this is the best, max reading taken so far
AirflowComparison.jpg
Only one minor and probably inconsequential correction. I don't have a 12" filter. I have the intermediate size (I believe it was marketed as 24") filter
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RFGuy
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Re: Rate of Air Flow vs Volume of Air Flow

Post by RFGuy »

dusty wrote: Thu Dec 01, 2022 11:46 am Only one minor and probably inconsequential correction. I don't have a 12" filter. I have the intermediate size (I believe it was marketed as 24") filter
Dusty,

That is good to know. That likely means that the base performance (without upgrade) is more similar between our DC-3300's. I really don't like the Shopsmith Wiki because I have found multiple errors in it in the past, but the Wiki page that incorrectly states the particle filtration for the filter hoods, also has supposed airflow differences for the 24" and 42" filter hoods compared to the 12" filter hood. Reluctant to post this below because I don't know that it is accurate, but...The 24" filter hood is supposed to have 30% more airflow than the 12" filter hood. Then the 42" filter hood is 110% - 169.7% more airflow than the 12" filter hood. IF we can believe this data on the Wiki then my original DC-3300 with 42" filter hood should have significantly more performance, but like I said I don't trust the Wiki and rely more on Shopsmith's main website and product pages, as well as past catalog data for "true" information.

There is NO way on planet Earth that my DC-3300 with 42" filter hood can achieve 695-890 CFM as the Wiki suggests. ;)

Excerpt to be taken with at least 1 lb of salt (from Shopsmith Wiki):
"Advantage of the 24" filter hood on DC3300 is that it increases airflow 30% or from 330 to 430 CFMs. 42" hood CFM range 695-890 hose is 2 1/2"."
Source: https://www.shopsmith.com/mediawiki/ind ... Filtration
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Re: Rate of Air Flow vs Volume of Air Flow

Post by john_001 »

RFGuy wrote: Thu Dec 01, 2022 10:51 am P.S. Just wanted to point out again that the original DC-3300 was spec'ed as a 0.5HP dust collector with a motor that draws 8A and has a 4 blade fan impeller. The DC-3300 upgrade/DC-6000 is listed as a 1.5HP dust collector with a motor that draws 8A and has a new 6 blade fan impeller.
These are strange numbers. I would have thought a 0.5hp motor would draw something like ~4A, and a 1.5hp would be more like about 12+.
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Re: Rate of Air Flow vs Volume of Air Flow

Post by RFGuy »

john_001 wrote: Thu Dec 01, 2022 4:55 pm These are strange numbers. I would have thought a 0.5hp motor would draw something like ~4A, and a 1.5hp would be more like about 12+.
Yeah, this has been a hot topic of discussion on this forum ever since Shopsmith released specs for the DC-6000 or the DC-3300 upgrade kit. The DC-6000/DC-3300 upgrade are supposed to flow 600 CFM.

For comparison, Baileigh has a 600CFM, 1.5HP dust collector Model # DC-600C that draws 14A. Rockler has a 650CFM, 0.75HP dust collector that draws 12A. Rikon has a 624CFM, 1HP dust collector Model 60-100 that draws 7A. Jet has a 650CFM, 1HP Model 650 dust collector that draws 7A. Shop Fox has an 800CFM, 1HP dust collector Model W1727 that draws 9A. Just a small sampling, but as you can see there is quite a range in current draw & reported HP ratings for similar dust collectors on the market. Of course, some of these may not be hitting their target airflow which might explain why some of them have 1/2 the current draw of the others.
Last edited by RFGuy on Fri Dec 02, 2022 6:53 am, edited 3 times in total.
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Mark V 520 (Bought New '98) | 4" jointer | 6" beltsander | 12" planer | bandsaw | router table | speed reducer | univ. tool rest
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Re: Rate of Air Flow vs Volume of Air Flow

Post by RFGuy »

Just to try to bring everything together, since there have been multiple past threads and information from Shopsmith on other threads related to the DC-3300 upgrade and the new DC-6000 dust collector. Below is the communication that was received from Shopsmith. IF I understand it correctly, then:

DC-3300 (original) should have 200 CFM (1 port), 150 CFM/port (2 ports open), and 100 CFM/port (3 ports open) - TOTAL = 300 CFM
DC-3300 w/upgrade kit OR DC-6000 should have 200 CFM (1 port), 200 CFM/port (2 ports open), 200 CFM/port (3 ports open) - TOTAL = 600 CFM

We are still in early stages in taking data on Dusty's upgraded DC-3300, but it doesn't look to me like they hit their design targets unfortunately. Below is the communication from Shopsmith and the comparison of original DC-3300 (42" filter hood) to an upgraded DC-3300 (24" filter hood) with ACTUAL measured data on both.
DC_3300_6000_airflow2.jpg
DC_3300_6000_airflow2.jpg (167.74 KiB) Viewed 1228 times
Actual Measured Data:
AirflowComparison2.jpg
AirflowComparison2.jpg (51.94 KiB) Viewed 1228 times
📶RF Guy

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Re: Rate of Air Flow vs Volume of Air Flow

Post by dusty »

The problem with my kludge connection of the anemometer to the DC was that I could not repeatably achieve a leak free connection; thus unable to get reliable results.

Attached is a pictorial of "the new concept".

Utilize the two holes in the meter to align to the kludge. With the leaks eliminated this is expected to provide repeatability as a result of aligning the aperture the same each and every time.

The face of the kludge will be soft foam pad so that when the meter is pressed against it the leaks will be sealed.

In the pictorial the yellow surface represents the soft foam seal.
anemometer coupler.png
anemometer coupler.png (109 KiB) Viewed 1149 times
Attachment is achieved by using a hose coupler between DC and the Anemometer. The kludge doers nothing more than encourage proper alignment and seal.
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Re: Rate of Air Flow vs Volume of Air Flow

Post by RFGuy »

Dusty,

What you propose looks good, but know that certain types of foam are more porous and can actually let air through in certain directions. Also the fit has to be very tight or glued - otherwise you will still have leaks between the anemometer and the foam and the DC-3300 I believe. I guess my question is what is good enough? I thought what you had already was sufficient for this testing. To truly get an air tight seal, I don't think what you show in the pic above will be sufficient. You would have to actually tape the interface between anemometer and DC-3300. I did this previously using my anemometer testing, but I could get within a few % by just holding my anemometer in the exact right spot and pressing it firmly against the DC-3300 and just logging the max reading I could observe. The anemometer fan housing is a little different on your device so I don't know if it would work better/worse than mine in this regard. IF taping doesn't bother you then you could just use your existing design and tape it really well to the DC-3300 manifold. Then do all measurements through that one port and repeat the 1 port open, 2 ports open, 3 ports open measurements again. Might be an easier option for you before trying to get the foam to fully seal.
📶RF Guy

Mark V 520 (Bought New '98) | 4" jointer | 6" beltsander | 12" planer | bandsaw | router table | speed reducer | univ. tool rest
Porter Cable 12" Compound Miter Saw | Rikon 8" Low Speed Bench Grinder w/CBN wheels | Jessem Clear-Cut TS™ Stock Guides
Festool (Emerald): DF 500 Q | RO 150 FEQ | OF 1400 EQ | TS 55 REQ | CT 26 E
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dusty
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Re: Rate of Air Flow vs Volume of Air Flow

Post by dusty »

RFGuy wrote: Sat Dec 03, 2022 8:40 am Dusty,

What you propose looks good, but know that certain types of foam are more porous and can actually let air through in certain directions. Also the fit has to be very tight or glued - otherwise you will still have leaks between the anemometer and the foam and the DC-3300 I believe. I guess my question is what is good enough? I thought what you had already was sufficient for this testing. To truly get an air tight seal, I don't think what you show in the pic above will be sufficient. You would have to actually tape the interface between anemometer and DC-3300. I did this previously using my anemometer testing, but I could get within a few % by just holding my anemometer in the exact right spot and pressing it firmly against the DC-3300 and just logging the max reading I could observe. The anemometer fan housing is a little different on your device so I don't know if it would work better/worse than mine in this regard. IF taping doesn't bother you then you could just use your existing design and tape it really well to the DC-3300 manifold. Then do all measurements through that one port and repeat the 1 port open, 2 ports open, 3 ports open measurements again. Might be an easier option for you before trying to get the foam to fully seal.
Before I get started on the kludge I'll give taping a try.. I have some two sided carpet tape that just might work. I think I may have some flexseal to try.
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