Dust collector replace bottom bag with filter bag?

[Frank DiSessa]

I have a JDS 1.5HP dust collector with a 1 micron canister on top.

I have a Oneida dust deputy on the intake side with a 25gallon drum.

I hardly see any dust getting to the bottom bag on the dust collector.

Does it make sense to replace the bottom bag on the dust collector with another canister or a filter bag to increase the air flow?

[michael dilday]

Are you getting dust and chips in the 25 gallon drum?

[Frank DiSessa]

yes. Dust Deputy is grabbing almost everything.

[Doug Garson]

Excellent question, in theory yes you should get more flow. By increasing the outlet flow area you reduce the back pressure on the fan and thus you should get more flow. Whether it would be substantial is harder to answer. You could try an experiment, take the bag off, turn the machine on and see if you notice more flow, somewhat subjective but maybe worth a try. If you can move it outside you could see if the dust pickup is improved without filling your shop with dust.

[michael dilday]

You need to measure air flow at an open gate. Getting dust in the filter bag is not an indication of adequate airflow. With proper air flow and a good cyclone separator you will get almost no dust in the canister bag. I have a Jet JCDC-3 cyclone with canister filter and a 66 gallon drum. I have paddles with a handle that cleans the filter. The filter is probably 5+ years old and gets daily use. I can empty the 66 gallon drum probably a dozen times before I need to empty the small bag under the canister. I get great air flow.

[David Buchhauser]

Something like this may be useful for measuring your airflow.
David

https://www.amazon.com/Digital-Wind-Speed-Anemometer-Handheld/dp/B07MVYCQJZ/ref=sr_1_1_sspa?gclid=EAIaIQobChMIiKextNTu5wIVE8pk Ch2orgbeEAAYASAAEgKShfD_BwE&hvadid=409901643255&hvdev=c&hvlocphy=9030244&hvnetw=g&hvqmt=b&hvrand=14753294409127645758&hvtargid=kwd-30498480&hydadcr=9006_11532205&keywords=anemometer+portable&qid=1582700947&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzVU5FMEhBTklHQlRSJ mVuY3J5cHRlZElkPUEwNzI0ODU1MUdUNkFEU1lFQjkyNyZlbmN yeXB0ZWRBZElkPUEwOTE4MDQ4MVdNSzRDS084MlM4RSZ3aWRnZ XROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05 vdExvZ0NsaWNrPXRydWU=

426793

[David L Morse]

I hardly see any dust getting to the bottom bag on the dust collector.


yes. Dust Deputy is grabbing almost everything.

Then your system is handling the dust exactly the way it should. Too little airflow for the cyclone would pass more dust to the bag under the filter.

Which Dust Deputy model do you have? There are at least four different sizes.

A clean filter will have very little resistance to flow, especially on such a small dust collector, unless it;s severely undersized. How big is your filter?

Are you saying that you don't have enough airflow at the point of pickup? Having a cyclone in the system in addition to the existing separator (aka bag holder) will certainly cause reduced airflow. So will a lot of other things.

[Bob Riefer]

Does it make sense to replace the bottom bag on the dust collector with another canister or a filter bag to increase the air flow?


Wynn Environmental helped me select the canister for my setup and told me that one would be sufficient for my 3 hp unit... their reasoning was that once system loss (ducting, leaks, cyclone) were accounted for the airflow would be low enough that 1 canister could handle it. They recommended that I start there and judge the results over time to decide if stacking another canister would make sense. My system would collect small animals, tape measures, a stray coffee cup... so I haven't felt the need to further upgrade. This is from the perspective of a company that specializes on this topic, and stands to lose money by convincing me not to buy another one of their products. Maybe not super scientific on my side, but makes me trust it a bit more.

In your case, the starting point (JDS 1.5 hp) is smaller, so I would reason that the thought process above easily holds true for your case too (assuming properly sized canister was selected). Again, I'm not Mr. Science, but it seems reasonable to me.

As for a filter bag... If you arrive at the conclusion (like I did) that another canister is probably not needed, then I wouldn't even bother going down the thought path around filter bags... you're already at the "best" level of filtration products by using (a presumably high quality and properly sized) canister, so adding a filter bag would be a step in the wrong direction in my opinion.

[Frank DiSessa]

Thanks to all for the replies.

My main issue is that the air flow is reduced on the intake of all the machines. Before I had the dust collector (1250CFM) connected to machines individually with 4" 20' flex hose. Now I have added the Oneida AXD002030A Super Dust Deputy and 4" sewer pipes to all the machines (3 total) on the ceiling with electronic blast gates to save me the problem of having a long hose on the floor and forgetting to attach it most of the time. I think both the extra piping and dust deputy contribute in the reduction of air flow. Router and table saw dust extraction is OK, but now my jointer planer is not grabbing the chips like it used to and I hate having a lot of the chips escaping onto the floor.


I think I might have to increase the dust collector size to get back to the performance I had before with the jointer planer. Canister on the JDS 1.5HP dust collector is standard that comes with the machine:
machine link: https://www.amazon.com/JDS-14031-Dust-Force-1250-Collector/dp/B000078UUU
Canister link: https://www.amazon.com/JDS-16002-1-Micron-Dust-Force-Collector/dp/B0007Y75J8/ref=cm_cr_arp_d_product_top?ie=UTF8

I think I will go out to get an airflow meter to test the airflow as a first step.

[David L Morse]

First problem is the 4" ducting. Replace that with 5" for a big boost in performance.

Next, consider deleting the collector ring (bag holder) along with the 5" hose and reducer on the outlet of the blower. Replace it with a transition something like the one in this build:

426810

That will more than compensate for the addition of the SDD.

If all that fails then think about a bigger blower.

Or, just buy a 3HP cyclone, e.g., Oneida V-3000.

[Frank DiSessa]

First problem is the 4" ducting. Replace that with 5" for a big boost in performance.

Next, consider deleting the collector ring (bag holder) along with the 5" hose and reducer on the outlet of the blower. Replace it with a transition something like the one in this build:

426810

That will more than compensate for the addition of the SDD.

If all that fails then think about a bigger blower.

Or, just buy a 3HP cyclone, e.g., Oneida V-3000.


Hi David,

I looked at the price of 5" piping and it is an order of magnitude more expansive than the 4" Sewer piping I'm using now - so this is not a good option for me. I thought about going to a 3hp 1900CFM like below from Busybee:
https://www.busybeetools.com/products/dust-collector-3hp-1-micron-bag-csa-ct118.html

If I bought the above Dust Collector then I would probably need a relay to switch my vacuum on as I have an 115V IVACPRO that can only handle 1.5HP DC. The boost would be 650CFM in theory, but I really doubt these numbers are accurate with all the piping and machines in the system. Hope that would be improvement enought to get things back to the way they were...

[michael dilday]

This is what I have and it works great.

https://www.rockler.com/jet-3hp-cyclone-dust-collector?gclid=CjwKCAiAy9jyBRA6EiwAeclQhJRhjl1xkX vduRKVPTuAHyauxpIvkhRBgJ9ARpIW9VR2NJBekG8YPBoCydAQ AvD_BwE

[Doug Garson]

Still think my suggestion to temporarily remove bag has validity. If you remove the bag and don't notice any increase in flow then you know for sure adding a second canister won't help and all it will cost is a bit of your time. You could also contact Wynn Environmental with your question.

[David Buchhauser]

+1 on that!! I would measure the airflow cfm with the bottom bag removed to see if it makes a significant difference.
David

[David L Morse]

Hi David,

I looked at the price of 5" piping and it is an order of magnitude more expansive than the 4" Sewer piping I'm using now - so this is not a good option for me. I thought about going to a 3hp 1900CFM like below from Busybee:
https://www.busybeetools.com/products/dust-collector-3hp-1-micron-bag-csa-ct118.html

If I bought the above Dust Collector then I would probably need a relay to switch my vacuum on as I have an 115V IVACPRO that can only handle 1.5HP DC. The boost would be 650CFM in theory, but I really doubt these numbers are accurate with all the piping and machines in the system. Hope that would be improvement enought to get things back to the way they were...

The usual approach to 5" ducting for hobby shops on a budget is 26ga (not 30ga) HVAC snaplock pipe. That's cost competitive with PVC.

The performance increase you might with the linked DC depends on the size of the impeller in your JDS unit. If it's also 12" like the Craftex there will be very little change. CFM is determined by fan pressure and total system resistance. You have so much resistance on the intake side that reducing the resistance on the outlet will not change the total resistance by much. If the JDS has a 10" fan then you will see roughly a 20% improvement.

4" duct has three times the resistance of 5" duct.

A simple test is to remove the connection to the SDD and give it a feel. Do yoou have an ammeter? If so you can get some very informative relative flow measurements.

Edit to add:

If your current unit has a 12" fan you can do a quick test to simulate the switch to the Craftex. Disconnect the flex hose from the outlet of the blower and see how much subjective change in flowrate you get. Obviously you don't want to feed any dust to the system in this condition but it will give you good indication of the increase in flow you would get if there's no difference in fan diameter.

[David Buchhauser]

Do yoou have an ammeter? If so you can get some very informative relative flow measurements.

Hopefully you are referring to an anemometer for measuring air flow, and not an ammeter which is used for measuring electrical current. The anemometer approach has already been mentioned several times in this thread. I suppose it helps to read the entire thread.
David

[David L Morse]

Hopefully you are referring to an anemometer for measuring air flow, and not an ammeter which is used for measuring electrical current. The anemometer approach has already been mentioned several times in this thread. I suppose it helps to read the entire thread.
David

No, an anemometer has well known issues measuring airflow in dust collection systems. I'll not repeat those here, hopefully you've read all of the threads discussing this.

I am most definitely referring to an ammeter. Motor current (and even better if you can measure it is input actual power, not apparent power) is a very good indicator of airflow (actually mass flow or SCFM rather than ACFM).

[jeff norris 2011]

Easy experiment. Take the bag off and you will see what no restriction will be. If it is better, than more filter area will help.

I have made a changes recently that are dramatic enough that no measurement was needed, I could see, feel and hear the added air flow.

I suppose for a very low tech way of measuring how well the air is moving you can rig something up to keep a dust port at a constant height from a table and pick some objects to get sucked up. You go with a variety of weights - ie several small offcuts increasing in size or using a measurement of sawdust to see how much is collected. Run a before and after test and see if no filter picks up heavier object or more sawdust.

[glenn bradley]

Keep in mind that a cyclone puts a terrific hit on your airflow even for blowers that are designed as part of a cyclone. When you add a cyclone ahead of a blower that is not designed for it, the hit can be even more substantial. This should be expected. You are adding something to the path, yes? Having the benefit outweigh the impact is where the balancing act comes in.

[Frank DiSessa]

Tried removing the bottom bag on the dust collector and noticed there was a little improvement, but nothing great. I then rearranged my piping to get the jointer planer close to the dust vac with only one turn - this did the trick. Other machines are also working fine.

Thanks to all that responded.

Regards,
Frank