My New 4" Top-Hat, 12" Tapered Square Funnel, Photos

[flagelpater]

I am a newbie

Top-hat About as close to 100% as I could ever imagine.

Manifold is made with ASTM F 810 MS  100 MM   = 4 inch     Waste Pipe Smooth Wall

4 inch Top Hat Separator

Rectangular Inlet  2 X 4 inches

Non Bellmouth 2 inch outlet, set at center of vertical chamber.

Inlet is 4 " pipe centered on inlet.  Left and right side is obstructed by opening but top and bottom are clear.

Inlet nozzle left side is straight in and the right side tapers to derive the 2 " opening.  This should help the airflow align with the wall of the top-hat.

1/8 inch masonite was used for the side wall.  The height was 4.5 inches so that the wall extends below the baffle without a seam.  Learned from the internet that bending is made very easy by wetting with 409 detergent 5 minutes before bending.

Slot is according to the plan and 1.5 inches.  ¼ inch plywood, smooth, no tapering for the baffle.

Outlet is designed as a metering orifice.  Piece of female end of 4" pipe is centered around outlet of top of the top-hat.  90 degree fitting is placed inside the female fitting.  Concentric orientation.

Square Tapered Funnel attached below top-hat dumps debris into the catch bucket.  Top opening 12 inches bottom opening 6 inches square.  Sides are made of masonite. 6 inch  high square chute   12 inches tapering to 6 inches.  This is located right below the baffle.

5 gallon bucket used for catch bucket.  The bucket has most of what you need to hold it tight to the bottom of the  funnel.  With the bucket handle up, attach a wire about 2 inches forward, towards you, of the handle attach point so that it can not slide on the wire handle.  Then attach the other end of the wire to a point on the funnel structure directly above the handle attach point, or a little aft of that location.  Now buy pulling down on the handle it will lift the bucket up tight against the funnel.  Either use a bungee or suitable fitting the keep the handle in that down position.  To remove the bucket just let the handle move up and slide the bucket out.

I have run two buckets full of sawdust and some larger debris through the top-hat an zero dust has been found in the shop-vac.  The filter in the shop-vac is also free of any visible debris.  I only have a table saw and chop saw generating chips.  I did add small cut off chips and some small pieces of tape to the mix.

Copious amounts of Duct Tape.

Shop-vac 12 Gallon 6.0 HP

Poor performance until I changed to 2.5 inch flex hose.  The 1.25 inch hose was too restrictive and also was prone to blockage.

Am a newbie at this but I have installed a couple Home Vacuum Systems and plan on using some of the lessons learned.  No 90 degree fittings, use two 45's, sweeping turns.

Only drop input into the top of the manifold, never insert input on the bottom of the manifold pipe.

Has anyone moved the Shop-vac to the garage to reduce the noise?
If I brought the output from the Shop-vac back into the shop would that bring all the noise back into the shop?  Don't want to give up conditioned air!

Should I make my own Blast Gates or buy them?

Thank you in advance.  I have learned a lot over the last few days.  This thing works GREAT!

Still trying to figure out how to send photos!!!!!!!!!

[tvman44]

Can't wait to see pictures!  :)

[flagelpater]

How do I insert the photos?
I have them on my desktop.

[dabullseye]

when you start a new topic or reply to one. under the box where you type in stuff is an attachment options. you have to be signed in to see this

[flagelpater]

I hope this works.
Sorry for the quality because they are from my cell phone.

[flagelpater]

Thank you Dabullseye

More Photos
Can someone explain the function of the bell mouth outlet? 

Is it to not let fines go out?

[galerdude]

Thank you Dabullseye

More Photos
Can someone explain the function of the bell mouth outlet? 

Is it to not let fines go out?

Nice job!
I think I read where the bell mouth adds a small measurable amount to the efficiency of the overall Thien Separator. I would hope someone more knowledgeable than I, could chime in with more facts on it. I've discovered that using Phils basic design and theory, and winding up with a working system, that life is good  :) :) :)

[retired2]

The simple answer is air enters a pipe more efficiently through a bellmouth than it does through a straight ended pipe.  There are a number of posts on this subject.  Search bell mouth and you should find them.

[flagelpater]

Thank you for your reply's.

That is what I was wondering about.  I did read about them here on the forum but never saw what they actually did to make them improve airflow. 
I am going to make a bellmouth by heating the end of the PVC and uniformly press it into shape in my bench vise.  Not sure how much of a change I need to make?  Some that I have seen in here are like a flange and others are more like a bellmouth.  If all it does is help the airflow find the opening it sounds like Trumpet Shape would be okay.

[retired2]

Thank you for your reply's.

That is what I was wondering about.  I did read about them here on the forum but never saw what they actually did to make them improve airflow. 
I am going to make a bellmouth by heating the end of the PVC and uniformly press it into shape in my bench vise.  Not sure how much of a change I need to make?  Some that I have seen in here are like a flange and others are more like a bellmouth.  If all it does is help the airflow find the opening it sounds like Trumpet Shape would be okay.

Trumpet shaped is best.  One of my posts has a diagram of different style entrance shapes and the relative performance of each, but as I said trumpet is best.  Also, I think there are some you-tube videos showing someone doing exactly what you are planning to do.  The idea of a bellmouth on the outlet of the separator came from an article I read about the benefits of rounded corners for machine pick-up ports versus sharp corners.

[flagelpater]

Thank you retired2. 
I will look for the you-tube. 
I guess I should maintain the same distance off the baffle?

[Schreck]

I guess I should maintain the same distance off the baffle?

That is a good question and I don't recall it being discussed: if you add a bell mouth, should you maintain the same distance from the baffle that you would have with a plain pipe?  Retired2 may have experimented with this on his build. 

[retired2]

I guess I should maintain the same distance off the baffle?

That is a good question and I don't recall it being discussed: if you add a bell mouth, should you maintain the same distance from the baffle that you would have with a plain pipe?  Retired2 may have experimented with this on his build.

Yes, the long thread on my build does include a data table showing air flow changes with the outlet pipe set at different heights.  To save you all the trouble of looking, the difference is negligible, and probably within the "noise" level of the testing procedures.

What the data does not address is whether separation is better at one location than another, so I've pretty much stuck to Phil's recommendations.  I do seem to recall that if you deviate from that recommendation, placing the outlet lower is better than higher.

[giovanotti]

Hello,
question for experts: basic design positions outlet in the center of the separator circle (looking from the top).

What about positioning it off center in a way, which is used for radial ventilators?

[galerdude]

Hello,
question for experts: basic design positions outlet in the center of the separator circle (looking from the top).

What about positioning it off center in a way, which is used for radial ventilators?

Interesting.
Anxious to see your test results and findings.
I understand Phil did various arrangements when initially designing the separator so hopefully he will have an opinion for you.
Best to you on your mods and execution.