J. Phil Thien's Projects

I did this so I could remove the filter without the need to remove the bag and separator.

Well, FWIW, the baffle that I took out of the 55 gallon separator can no longer work there. I cut it down to fit the ring on the HF DC.

Looking at the inside of the PSI unit you attached pics of it looks like it has / had some sort of spiral ramp (?) instead of a cone below the filter. Looks like you cut it out in favor of the wooden ceiling / tube arrangement.

MY intended LONG TERM application is going to be a 5' main with drops to my exisitng 4" blast gates instead of splitting to 2 4" mains. I am thinking about using a 5" blast gate to block off the run of the main that goes to the end of the shop, OR the run that goes overhead so I can basically reduce the volume being pulled against.

The mounting holes for the baffle need to be figured out. Pretty sure I can't use the ones I had originally in the drum baffle as they are too close together. Planning on filling the holes with putty and sanding smooth. Attachment will be 1/4 - 20 threaded rod, washers, and nuts / nylock nuts arrangement. Need to figure out how to orient the baffle with the neutral vane. I am going to assume the start of the full width is just before the opening of the neutral vane where it dumps so that the air / dust rides along the wide part enough before it drops in to the drop slot.

Also, drop slot was made 1.5" wide. should it be wider since this is in a dust collector arrangement and not a shop vac?

Quote from: dbhost on January 01, 2022, 07:29:31 PM
I am unsure about that Penn State unit you measured against though, does it lack any sort of cone, or inside anything in the ring?

It has no cone.  It came with a ramp that pushed incoming air downwards, but I removed it when the baffle was installed.  The chimney was added because there was no cone.  Note the increase in airflow when the chimney diameter increased from 6 to 8 inches.  A 12 in. chimney would be less restrictive.

Quote from: dbhost on January 01, 2022, 07:29:31 PM
I might just have to soucre up 10' of 5" and see if I can't measure pre and post baffle airflow with the cone. I REALY want to know...

I don't think a measurement made at the impeller intake is meaningful since that is not how the unit will be used.  If you are using 4" flex hose to your tools, the tool end of the hose is where you should measure the airflow.  If you attach the 4 in. hose to a reducer (increaser) with perhaps a short length of 6" duct, the airflow will remain the same but the velocity will drop, perhaps low enough that you can measure it with your instrument.  The instrument will partially block the duct end, so the measurement won't be very accurate but it will allow you to compare different measurements as you change your system. 
Skip the 10' of 5" duct because your measurements can't be compared to those I made with a pitot tube.

Last photo shows 1.5 HP Penn State DC at left and the HF DC at right with the stock impeller.  After testing the airflow, I returned the HF unit.  The center DC is the 2 HP Grizzly unit I used for my tests last year http://www.jpthien.com/smf/index.php?topic=1426.0

Reviewing your numbers, and the hit you took on airflow, is not all that reassuring. Unfortunately my anemometer doesn't read fast enough air speed to be useful for anything at the impeller on the DC.  I do know that a 30% drop after 10' of 5" ducting however is substantial enough to give me pause.

HOWEVER, I looked at how yours was set up, and yes the, ceiling or whatever you called it, with the 6 or 8" neck would likely serve to provide a restriction.

I know the neutral vane puts everything in the ring under the cone, and forces it to spin around the outside of the ring, kind of a weird sound with shavings actually, I know the opening in the ring is something like 12", maybe a little less,..

I do expect SOME restriction due to the baffle as it is a baffle after all, but I am not expecting to see a LOT of restriction...

I am unsure about that Penn State unit you measured against though, does it lack any sort of cone, or inside anything in the ring? That would explain a LOT of the restriction right there...

I might just have to soucre up 10' of 5" and see if I can't measure pre and post baffle airflow with the cone. I REALY want to know...

Quote from: dbhost on November 15, 2021, 06:41:45 AM
I am trying to improve airflow in my DC and condense my workshop as I am going to move from my garage workshop that is 18x20, and into a shed workshop that is 12x16, I need to downsize!

My current rig is an older HF 2HP DC with a Wynn 35A, and I go out of the DC via a 5" hose to a 55 gallon blue poly drum separator with a side inlet.

I want to remove the poly drum.

So plan at this point...

#1. Upgrade the pitiful stock HF impeller with a Wen impeller. Already on order.
#2. Build separator for mounting in the ring of the DC.
#3. Move my 5" connection direct to the DC bypassing the drum entirely.

This begs the one BIG question. How do I mount both the separator, AND the 35A filter?

I am assuming the 35a more or less has the one method of the turnbuckles to mount, so that leaves how to mount the separator.

So if you have done this, could I bother you to chime in and post some ideas for mounting? I am thinking about screws through the ring into the separator, and one or two threaded bars to stand off the "loose end"

I couldn't find a photo of your old setup, but 55 gallons is pretty big all by itself, so getting rid of that will be a good start.
I have been using a baffle inside the ring of my single stage dust collector for 8 - 9 years now.  I always intended to make a tophat but never got around to it.  I collect sawdust with a plastic bag under the ring.

I made some fairly accurate measurements of my baffle-in-ring setup back in 2013 or so that you may find helpful:
http://www.jpthien.com/smf/index.php?topic=1109.msg6089#msg6089
My ring had a spiral ramp, which I removed, so I installed a plywood ceiling and chimney.  The net effect was I built a top hat using the ring.
The HF ring has a collar above the inlet, so you don't need a ceiling.

The Wynn filter website has photos of different dust collector installations that you may find helpful as well.

Updated info here.

After further digging, and putting a bit of trust into Phil on the matter, although I wish that he could link the tests / articles but  apparently Fine Woodworking did a test of the Thien Baffle IN the ring vs. external, and apparently the in ring configuration produced reportedly negligible impact to airflow into and through the DC, which is what I am aiming for. So I am thinking about going for the separator in the ring and calling it good...

Quote from: phil (admin) on May 03, 2014, 07:00:18 AM
The losses from a baffle INSIDE the DC's ring are substantially lower than those of a top-hat separator.  Fine Woodworking's test indicated they saw little initial loss from adding the baffle to a Jet dust collector.

It is probably substantially easier to add a baffle to your existing DC ring than building a top-hat, as well.

The only advantage to the top hat really is that it prevents larger chunks of wood or screws or whatever from hitting your blower wheel.  But the blower wheels inside single stage DC's are designed with this possibility in mind.

@phil

I am guessing you have been AFK for a bit. I sure could have used this reassurance...

I have the baffle taken out of my 55 gallon unit and have been straddling the precipice on whether to cut it down for my DCs ring, not sure who it was, but the member that had the Plumb Crazy HF DC with a neutral vane and a baffle had the idea, but I never saw test results.

My main goals here are...

#1. Keep my airflow high in order to insure dust, shavings, and chips keep moving to the collector.
#2. Keep the dust, shavings, and chips away from the filter as much as possible to prevent clogging.
#3. Reduce the shop footprint of the collector and any separator. If they consume the same space, that is ideal. Where my 55 gallon unit was now has my roller stands, and one of my shop stools.
#4. Oddly enough, I want a clear dust vessel that I can view at a glance. Clear plastic bags are good by me. And my city recycler will take sawdust in plastic bags. I think that stuff goes to the paper mill...

I am MORE than willing to put my 55 gallon drum separator back together and use it for this test. I need data though.

My issue is this. My anemometer will only measure up to 69mph. so at the inlet of my DC, I cannot actually measure airflow, I exceed maximum measureable speed.

I have seen more than a few tests showing a Thien baffe, notably the top hat installs, but I assume others are similar, reduce airflow by somewhere around 45%.

I am wondering if the same is true with a baffle in the separator ring of the dust collector itself (post motor).

I can build and install the separator, however I have no means of measuring it if the air speed exceeds 69mph, which I expect it will / should.

What I am wondering, is has anyone done a comparison from pre, to post in ring baffle install, OR is there anyone in Houston Metro on here, that is interested in this data, that has an anemometer that can read much higher wind speeds than my puny one can that would be willing ot loan it to me or work with me to get this data?

I'd REALLY rather not buy another anemometer for this one data point. And I am pretty sure I will be able to get wind speeds at my duct ports with my existing one so no issues there...

Just saw your post.  An 8? inlet would not be helpful for this blower.  The relationship between the impeller and the housing affects blower efficiency.  The distance between the impeller and the inlet would increase because there is a profile to the blades of the impeller. See pix in reply 6 above.

I'm setting up a 2x72 belt grinder to grind knives.   A lot of guys just put a 5 gallon bucket under the grinder for the sparks and dust to fly into.   I'd like to create some suction under the grinder and I'm concerned about the sparks.   I'm wondering if anyone has used this system in my application?   Maybe by incorporating water on the bottom of the collection pail?