Another HF with SDD & Wynn 35A question! how much WC change should I see?

[Lane Hardy]

I have gutted a HF DC with the Stock separator ring and the stock impeller with a Wynn 35A2740 nano filter sitting on top of the Ring, the Supper Dust Deputy (SDD) is connected directly to a modified 6 inch intake on the blower ( I made a new blower cover out of 3/4 mdf and used a flanged 6 inch HVAC take off that fits directly into the suction side of the SDD)
I am using 5 inch ducting for machine connections.
the Filter is new I have not used it for saw dust collection, only testing.

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As you can see the blower exhaust directly into the stock HF ring no leaks in the system checked using a smudge stick.

The question what kind of WC change should I see from static (blower not running) compared to running.
things to note.
I made a manometer based on based DIY Tyler's for Testing a clean filter vs clogged.
I want to make a base line measurement to assess changes I make in ducting such as bends and use of flex ducting.
Currently in the configuration I have the manometer connected to top of the Wynn filter it will measure the decay of the filter efficacy with a rise in WC as the pressure inside of the filter increases thus pushing the water colum higher. This only measures how well the air is being exhausted through the filter.

What at I am looking for is a base line as stated before. I want to know how well the D.C. System is performing as it is connected to ducting and changes that are made with ducting.

Can a manometer be a good tool for this purpose and if so how and where should I connect the tubing for this measurement? I would think so 43 years ago I had a set mercury sticks to balance the carburetors on a Triumph Motorcycle. I would like others input!

How ever I do not have a pitot tube to compute CFM.
I am not really trying to derive CFM from the the tools at hand. The real test in the end is does it do the job I want it too? Remove the dust! And the fine dust. Although I would like to know.
i have seen Fan curves for this HF unit, however with the changes I doubt they mean anything.

some data collected!

I am at And Altitude off 1900 MSL (mean sea level) West Texas.
stock HF impeller
120 volts
blower running current measurement with a clamp on Amprobe.
condition: 11.5 amps with no filter or suction hose only the SDD connected
yea 2 HP yea right!!!! I am not going to try to guess what this motor is developing because I do not know what the real efficiency rating is. That being said it ain't 2 HP.
When the Wynn filter is connected and the dust bag on the bottom no suction hose on SDD 11.15 amps
this is telling me the lower amp draw is because the airflow is restricted by the exhaust through the filter.
(unrestricted no filter the current draw is higher 11.5 amps)

The Manometer home made 3/8 tubing with 3/8x 1/2 barbed nylon fitting sealed and tapped into a 11/4 inch pvc cap sealed to the top of the Wynn filter, 1/4 vent hole to cap with 1/4 hole sealed to connect to the filter no leaks.

WC displacement: with the system connected (5 inch ducting no reducers) I am seeing only a negligible rise in WC maybe a 64 of an inch. I guess this good.

any advice would be appreciated.

oh I did place a bag over the Wynn filter and sealed it airtight and observed a 3 1/4 displacement on each side of the tube for a total of 6.5 WC what are your thoughts on this performance? After all it is a HF blower.


Thanks Folks.
Lane



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[David L Morse]

... I want to know how well the D.C. System is performing as it is connected to ducting and changes that are made with ducting. ...
With the tools you have a good way to get that information is measuring motor current. You already have the 11.15A reading for unrestricted input. Call that 100% flow. Cover the input and make another current measurement. That will represent 0% flow. Now when you connect ducting and a machine port you can use the motor current measurement to interpolate a relative flow value.

When I measured the fan curve on my HF blower I recorded the current readings along with CFM and now I can easily estimate CFM by simply making a current measurement.
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...yea 2 HP yea right!!!! I am not going to try to guess what this motor is developing because I do not know what the real efficiency rating is. That being said it ain't 2 HP. ...
Correct. The fan is way too small to pull 2HP from the motor. A 12" fan could do it but the 10" fan pulls more like 1.2HP.


...oh I did place a bag over the Wynn filter and sealed it airtight and observed a 3 1/4 displacement on each side of the tube for a total of 6.5 WC what are your thoughts on this performance? After all it is a HF blower.
That seems low, mine measures 7.5". The altitude difference (I'm at 670') isn't enough to account for that much pressure difference.

[Andy Giddings]

Your clean filter WC measurement sounds about right based on what I see on a ClearVue system. A clean filter barely moves the needle on a 0-3" gauge. I would recommend a pitot if you want accurate airflow measurements. Dyer makes a range and their phone application makes the conversion of WC into CFM easy

[Carl Kona]

Lane,

The only reference I have ever seen for the HF DCs is the old review shown here: http://www.portercable.com/uploads/PCD/Documents/News/182DustCollectors.pdf

Since you only have a 10" impeller it can't develop very much SP as shown on the chart on page 67 (HF=Central Machinery). The only way I can see getting the number you want is to put your unit back to stock condition and measure with your equipment to match the chart in the review. Since that is not probably too enticing, David's suggestions is a great alternative.

Hope that helps. Let us know what you do.

Carl

[Larry Frank]

The review Carl Kona references is very good and presents the performance curves for a number of 1.5 - 2.0 hp dust collectors. Another good way to estimate your cfm is to use the homemade manometer to get static pressure and then use the curve to get cfm

[Lane Hardy]

Update on HF DC with SDD & Wynn 35A filter.
using information from Redoak49's post I connected my DIY manometer to the input of my intake 5 inch pipe, I am pulling 1 1/2 inches of WC on each side of the manometer for total of 3 inches that equals 600 CFM based on the Chart that redoak49 posted.
i can't complain considering it is HF blower with the stock fan and the Density Altitude is 2441 feet.
a 12 fan would make the performance even better.

Thank you all for your input on my posting.


Lane

[Carl Kona]

Lane,

I think you are close but it looks like you are comparing apples to oranges with the Redoak chart. That original chart is shown in the link I provided above. If you look at that chart it shows the HF machine maxed out at 536CFM @ 4.25" SP (bottom right of the chart). That is the stock machine. Any number below 4.25" is extrapolated. You are testing a system with a different (better filter) and a SDD cyclone added (usually ~35% drop in CFM). So you really can't use the Redoak chart when comparing your system. There is one data point close to yours in that is in this video https://www.youtube.com/watch?v=HaTrY-O7l5E&t=2s
He has the same setup that you have but vents directly outside. You could remove your filter and measure your SP to get a relative CFM number (his is 632CFM without a filter). The downside is he uses a handheld meter and looked for a maximum reading and only took one reading, which would be exaggerated. There should have been multiple readings at the inside and edge of the test pipe and averaged. I know from my own experience that the handheld meter can peak out 20-30% higher than an average of multiple readings. So although it is a data point it is likely on the high side and without a filter. There is another guy who did the 12"upgrade and added the SDD XL and I believe only read ~700CFM on his handheld (look for him on youtube)

Hope this helps. Let us know what else you find out.

Carl

[Lane Hardy]

Hi Carl,

Thank you for the feedback, however I need to add a few things that are different from the stock HF DC
that will explain the performance I am getting. I did mention stock HF D.C. But I should have stated stock impeller.
the changes that I made that are different from the Youtube link you posted is he is using a five inch pipe connected to the five inch port on the D.C. I made a new 6 inch hole in a new MDF fan cover and used a 6 inch HVAC takeoff that fits directly into the SDD. I get more airflow this way, in addition I do not have the 5 inch flex hose connecting the exhaust to the separator ring. The Fan curve that redoak49 posted was for a stock HF DC an the changes I have made would invalidate the results I agree, I would think that the changes I have made would be towards the plus side over HF fan curve.

Lane

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[Larry Frank]

I am really uncertain about the curve being not valid. The curve is determined by the impeller, the housing and the motor. If you change the filter, add at dust deputy or similar, you are really only changing the static pressure of the system and not the characteristic of the fan and motor. Does having a dirty filter versus a clean filter change the fan curve? No, it only changes the static pressure of the system. Perhaps, the curve does not extend far enough or to low enough static pressure but the general shape stays the same.

If you change the impeller, yes the fan curve will change. But all the other changes will not change the curve. You can only get so much of the small HF impeller. Another point to make is that running a dust collector with out a filter and much larger intake will lower the static pressure giving you higher CFM but you must be a bit cautious as you may be getting too many amps on the motor.

[Lane Hardy]

Hi Larry,

Would changing the intake from 5 inches to 6 inches change the fan curve? I think it would. I maybe wrong.
I have a digital amprobe and with this configuration I am only pulling 10.5 amps. With my 5 inch metal ducting an two blast gates.
Correction in my original post I said the dust bag was on the bottom I should have said the plastic dust bag on the bottom with the Wynn 35 A on the top.

[Larry Frank]

Changing the intake probably does not change the curve. It will lower the static pressure and move you on the curve and you get higher cfm.

If I have 6" mains on my dust collector but connect a 4" hose to it, I do not change the curve. I do increase static pressure and lower the cfm.

The fan curve is pretty much defined by the impeller and motor characteristics.

I tested my dust collector with everything from an 8" pipe to a 2.5" hose and many conditions in between. They all fit on one smooth curve of cfm versus static pressure. I would not run my dust collector with the filter off due to concerns of damaging the motor.

[Carl Kona]

Larry - you are correct in that the curve is the curve from the blower. What is done after that is where you land on the curve. The fact that the Redoak curve tried to recreate the curve from the article and in doing so created data points below 4.25", which is an extrapolation. I guess things were not adding up for me. Changed bag to Canister filter +10-20% CFM, add Cyclone -30-40%, add higher sea level -~10% and yet the result is improved performance?

Lane you are correct. Increasing the input port does increase CFM by about 10%, but only on the lower SP end of the curve. The improvement will evaporate as you increase SP.

You will not improve/gain SP by changing the input size, that can only be done by increasing the impeller diameter or the housing configuration.

At this point I think we are splitting hairs about data from an almost 10 year old review, a home made manometer and probably a less than 10 year old HF DC, which may perform differently. Without testing his manometer on his stock system and compare numbers, the chart to me doesn't mean much.

The bottom line, Lane everything you did improved performance overall. The SDD may have hit the CFM but improved it in the long run by having a cleaner filter.

Way to go. Let us know what else you do!

Carl

[Lane Hardy]

Thanks guys for the input! I am learning! From what I am understanding I am comparing a 12 volt rechargeable dust buster to a wind tunnel at NASA Langley! My anemic HF blower is the DustBuster. I need a bigger fan. Seriously if I had to do it over I would have bought a 5 HP 2 stage machine. But the the SDD was a gift and I had the HF dust distribution system another gift. My only outlay of cash has been the Wynn Filter $208.00 delivered. And several dollars on fittings.
and time! That is free these days.
i appreciate everyone's input, and Welome the knowledge that others have to offer.
I hope this discussion will help other woodworkers in decinding what route to Persu on the dusty road of chip collection.

Thanks guys,

Lane

[Lane Hardy]

Thank you Carl and Larry for your input and taking the time to share your thoughts.

Lane

[Larry Frank]

Carl --
I just checked about your comment that I extrapolated the curve. I did not and reproduced it just as it was in the Wood Magazine Article which shows the curve down to about 2.25" I am uncertain where you got the idea that I extrapolated or created data.

Here is the curve from the article. The HF curve is the lower one in the graph.

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[Carl Kona]

Larry,

You are absolutely correct. You are referring to the chart on page 68 which tests a 5" port. I kept referring to the chart on page 67 which uses a 4" port. So many people downsize to 4" pvc I didn't even think of the context of Lane's setup and the other curve on the next page. I also apologize for my 'extrapolate' comment. Re-reading it comes across the wrong way. What I was trying to say was the chart I was looking at went down to 4.25" (wrong chart) and your chart went lower. I thought it was a factor of the software extrapolating the data to make a longer smoother line. I didn't mean to imply you were making up data points.

Thanks for correcting me.

Carl

[Lane Hardy]

Wow now that we have cleared up�� I did not mean to start a war, just kidding Carl and Larry.
ok let me ask this question! I wil start with my anemic HF modified D.C. system.

stock HF fan: we will call it 10 inch. I not have put my Sarrete micrometer on it.
intake into Fan is now 6 inch dia. Direct connect to Supper Dust Deputy (no bends) (fan shaft is vertical)
exhaust of blower going into stock HF separator with a Wynn 35Anano filter on top and the clear dust bag on the bottom.
for ducting I am using 5 inch HVAC Duct and very short 5 inch flex hose for coupling two different 5 inch blast gates.
of the two fan curves which one should I use to help detrimen performance?
i have been taking the shotgun approach using my DIY Manometer and measuring the SP changes as I add or reconfigure bends and angles on my three drops. One blast gate 5 inches is connected to the bottom of the TS. I am considering an overhead TS pick up. To collect the dust on the table top. I am thinking that I might employ a 5 inch to 4 inch wye one 4 inch connected to the bottom of the TS and the other half of the Wye going to the top collector.
any thoughts on if this is a good idea? Considering the CFM and what ever the velocity of the air actually is?
perhaps a smaller upper collection hose to increase the velocity considering that two four inch exceed the volume of the 5 inch main.

any thoughts?
oh one other! Question, I have read that the Rickon blower fan will fit in the HF housing and another fan that I can not call will fit as well. I do know that I will need to increase the ID on the fan shaft on the Rikon to fit the shaft on the motor that is not a problem.

I am not worried about the current draw I have an amprobe and I am no where near 14 amps.
my altitude is 1900 feet Mean sea level, when yon consider the temperature the density altitude hovers around 2400 or more on 67 degree day. So pulling too much current is not an issue.

Lane

[Carl Kona]

Lane,

It is great you are really stretching that HF DC to get the most out of it! The curve on page 68 will be in the neighborhood but still meaningless to me. Your system left the 'Stock' station awhile ago. If you look at the curve on page 69 of that article you will see various filters attached to the same DC. As you provide more filter area (less motor restriction) your curve chages. As you can see 4 filters, 4 curves 1 blower. The same is true with changes to your opening. If you look at a fan table like this one on page 6 https://www.cincinnatifan.com/catalogs/PBSCatalog.pdf the PBS-14A has several impellers shown in rows with different inlet diameters. As you look at the same impeller in the same housing with 3 different inlet diameters you will see the CFM increase with larger diameters. 3 diameters 3 different curves for the same blower. So can you tell me what a fan curve would look like on your system now? IMO it can't look like the tested unit. Now if you look, still within the PBS-14A rows, at the 12 1/4 impeller vs the 14 you will see significant increases in both CFM but also a couple more inches of SP. If you also look at the same impeller 14x3 1/4 in a different housing PBS-15A you will see even different curves. So your system changed as soon as you changed the filter and lowered the restriction on the output.

Another improvement you can look into fairly easily is to disconnect your output from the filter/separator assembly and measure the SP, then attach the separator assembly without the filter attached to see how much the separator restricts your exhaust air. An improvement would be to exhaust directly into the filter without the baffle (but it may not be enough of an improvement to bother with).

As for your TS connection, splitting your 5 into 2 4s would not be as effective as a 4 and a 3. Look at the area of the 5 (just under 20 sq-in) and a 4 (about 12 sq-in). So you will be going from a smaller area to a larger area.

Hope that helps. Let us know how you make out.

Carl

[David L Morse]

Lane, it seems to me that it would be a lot simpler to just measure your flow instead of trying to guess at fan curves. Use a DIY Pitot tube (http://www.sawmillcreek.org/showthread.php?197861-How-to-measure-dust-collector-performance&p=2096532&highlight=#post2096532) and your DIY manometer and find out what you actually have. The only "calibration" you need to do is calculating your air density and it sounds like you're already on top of that.

FWIW I'm using two 4" ducts to my table saw and I get enough lift on the topside to keep the duct clear. It's best to minimize the amount of flex in the path because it adds a lot of resistance unless it's pulled absolutely straight. Bends in that stuff cause more pressure drop than I ever expected.
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[Lane Hardy]

Carl and David thank you for all the input, for the link to Cincinnati Fan. Wow I wish I had seen this in the begaining of this project. Had I had this information available I would have sold the HF D.C. On Craig's list even thou it was a gift to me. And started with a new 2 stage system and perhaps upgraded the filters if it would have helped.
I feel like I have a well filtered 12 volt portable handheld dust buster when I need a sawmill D.C. System. Well I may not need a Sawmill DC but more CFM would be nice however then I would have to use substantially heavy ducting.as it is
i am a one tool at the time shop as it is. And it is a hobby. Thanks for the idea of going from a 5 inch to a 4 inch to the TS with a 4 x 4 x 3 wye the 3 will go to the overhead drop down. the 5 inch flex is only about 5 inches long to make up couplings. And where possible the couplings ID are smooth and contact each other so the corrigations of the flex pipe is not incountered by the airflow.for the Wye I will have it made locally I will have 5 inches on one end and it will tapper down to 4 inches the 3 inch will be the wye leg. This way there are no sharp steps that will cause a higher SP (parisitic drag)
Again thanks for all the help gentlemen, this weekend I will digest the Cincinnati Fan website.


Lane.

[Lane Hardy]

David thanks for the Overhead layout you have, I hate ask can you give me the details of your D.C. System HP, your Alt I think you said 600 feet. The reason I ask you say you are useing two 4 inch lines one for the over head the other to the TS base, what size main plenum do you have before you split the two 4 inches?

Lane




Lane, it seems to me that it would be a lot simpler to just measure your flow instead of trying to guess at fan curves. Use a DIY Pitot tube (http://www.sawmillcreek.org/showthread.php?197861-How-to-measure-dust-collector-performance&p=2096532&highlight=#post2096532) and your DIY manometer and find out what you actually have. The only "calibration" you need to do is calculating your air density and it sounds like you're already on top of that.

FWIW I'm using two 4" ducts to my table saw and I get enough lift on the topside to keep the duct clear. It's best to minimize the amount of flex in the path because it adds a lot of resistance unless it's pulled absolutely straight. Bends in that stuff cause more pressure drop than I ever expected.
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[David L Morse]

Lane, you can see the DC in the background of the first pic. It's the same HF unit you have, just in the older Green paint. I recently modified the intake so I can use 6" hose. Two 4" hoses were adequate for the table saw but my jointer/planer only has a single port and a single 4" hose wasn't doing the job.

Before I modified the DC I used two 10' hoses connected to it's plastic wye. The hose I have is very flexible so without care in routing it the suction could pull it into odd twists that made an observable difference in flow. The PVC, even with all of the fittings, is a little better than the best arrangement I could get with the hoses and a lot better than the worst. I'm using a 6x6x4 wye with a 6x4 reducer to split into 4" lines. I kept my DC mobile so I use 6" flex to connect the wye to the DC.

I did some testing on a 10' length of my 4" flex. When stretched tight it had a flow resistance equal to 24' of PVC. When compressed to 5' but kept straight it increased to 64'. Stretched tight with 2 90 degree bends is 61' and tied into a random tangle 214'.

My altitude is 670'.

[glenn bradley]

I have witnessed Beranek's Law in action in a previous career; it is so true. I have also noticed that Beranek's Law frequently applies to dust collectors as well. :)

[David L Morse]

I have also noticed that Beranek's Law frequently applies to dust collectors as well. :)

I wasn't actually thinking about loudspeakers when I chose that for a sig.;)