Piping new-to-me DC

I picked up a Grizzly 2HP G1029 DC with the 6" inlet. I have an Oneida cyclone in boxes I picked up years ago, but have not figured out how to make the head height work yet. In the meantime, I have this to work with.

I am planning to rebuild the stand and mount to remove the 90 degree flex tubing. I am also planning to use the homemade trash can separator I built based on plans from SMC. These are the plans with the 90 elbow going into the top of the lid, the baffle in the middle similar to Thien baffle, and the outlet from the middle. I use it now with my 1HP and I like the hard bin and extra capacity.

So the questions are:

The G1029 has a 6" inlet that measures similar to sheetmetal duct 6". Does the sheetmetal duct actually match up ID for OD?

Has anyone built a trash can separator with 6" inlets and outlets? What did you use for the inlet elbow as I am at a loss to find a long radius sheetmetal elbow?

Or more exactly, if I use a 6" PVC elbow in the trashcan how do I transtion PVC to sheetmetal to connecto to the DC? PVC 6" measures 5/8" diameter larger than the sheetmetal.

I doubt a trashcan is big enough for 6" airflow to allow much to drop out and not be picked up.
Bil lD

Either way I am looking for options to get from the 6" actual inlet to 6" PVC.

Fernco 6" rubber adapter sold in most hardware stores. I recently purchased one at Home Depot for $17.00

I used a Thien baffle once but I am not a fan. My experience is that it was pretty effective on larger pieces but did little to reduce the need for filter cleaning. For me, that is the major reason I want a pre-separator. I believe cyclones are much more effective at removing smaller particles so you can delay filter cleaning and still have effective dust collection. So I would not "mess around" with a trash can separator and just install the cyclone.

I use the 2hp HF DC and I modified the inlet to six inch to match the super dust deputy cyclone I use. I used only the motor and blower of the HF which I mounted to the wall with only a couple inches to the ceiling (8'). That wasn't hard with the HF, I just used it's normal mounting bolts into a piece of 3/4 plywood solidly screwed to studs in the wall. My Oneida cyclone is directly below the blower and sitting on a home made collection box made of plywood. I made the box about 18 inches square which is about the space required for the motor and blower. It has about 70 gallons of capacity. I exhaust outside so I have no filter.

I am unfamiliar with your equipment but I suspect you can do something similar to what I did if you want to. If you are happy with your pre separator just taking the large pieces out before the filter then your trash can separator may work fine for you. But if you want the filter cleaning to decrease, I strongly suggest a cyclone is the way to accomplish that. My setup is such that I can add a cartridge filter by a little replumbing if I want to switch to that later (if I heat and cool my shop at some point).

Thank you all for the input so far, but we are missing the questions.

In regards to the cyclone, I cannot find a 24" diameter 12" tall collection barrel nor do I think that would be an effective way to run a cyclone.

I am not adding a Thien Baffle to the DC. I am using the trash can separator with the lid design that has the elbow inlet at the edge, the outlet in the center, and internal baffle. With this design I am getting quite efficient separation. I don't know the exact particle separation effiency, but the chips reach the baffle before they begin to enter the DC. When starting with an empty drum and connected to the sander I do get a lot of material in the drum. Again this is the visible stuff, I don't know how much of the stuff not visible to the eye makes it to the DC bags. The "trash can' is a 75 gallon barrel with a intergrated wide point for a barrel lift so it is quite a monster of a barrel.

I tired the fernco on the DC inlet, but I could not get it to seal on the DC. Too much material (circumference and thickness) to shrink (cinch up) that much in diameter.

I'm in the process of converting a 2 hp Jet dust collector to a two stage. I'll offer some comments that may or may not be useful to you. First, Oneida told me that a 2 hp collector cannot support six inch ducting. It indicated that a 2 hp motor will not move enough air to move dust effectively in a six inch pipe. It suggested I use five inch ducting (with its Super Dust Deputy cyclone, which I had already purchased from Woodcraft). I've purchased some five inch spiral pipe (which is very nice) from Air Handling Systems, and it fits around the exhaust port on the blower unit. I am going to use a fitting, though, that will join the duct to the blower unit. I believe that will be cleaner and allow for a better and tighter joint. Based on reading a lot of forum posts on dust collection, I understand that using a well designed cyclone will produce better efficiency and results than a Thien baffle. I obviously don't know that for certain, but that's what most folks say. Five inch ducting and flex hose is substantial. It looks a lot bigger than four inch which means it will move more air with the right blower. Hope this helps. If I've mentioned anything that you understand as incorrect, please let me know.

Quote:

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Originally Posted by Jay Kepley

I'm in the process of converting a 2 hp Jet dust collector to a two stage. I'll offer some comments that may or may not be useful to you. First, Oneida told me that a 2 hp collector cannot support six inch ducting. It indicated that a 2 hp motor will not move enough air to move dust effectively in a six inch pipe. It suggested I use five inch ducting (with its Super Dust Deputy cyclone, which I had already purchased from Woodcraft). I've purchased some five inch spiral pipe (which is very nice) from Air Handling Systems, and it fits around the exhaust port on the blower unit. I am going to use a fitting, though, that will join the duct to the blower unit. I believe that will be cleaner and allow for a better and tighter joint. Based on reading a lot of forum posts on dust collection, I understand that using a well designed cyclone will produce better efficiency and results than a Thien baffle. I obviously don't know that for certain, but that's what most folks say. Five inch ducting and flex hose is substantial. It looks a lot bigger than four inch which means it will move more air with the right blower. Hope this helps. If I've mentioned anything that you understand as incorrect, please let me know.

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That is interesting since the Onieda designed DC system that is too tall for me to install came with a 2HP motor 13.5" fan (IIRC) and 6" main ducting. It is Oneida's specialty, but i think some information waas relayed poorly. A carte blanche statement that a 2HP motor will not support 6" duct cannot be made. It is TOTALLY dependent on how big the system is (how much duct) and the fan curve. In my shop, the DC is centrally located with the longest run (for the table saw) being 20' maximum. Based on the spreadsheet from Bill Pentz, 6" inlet, 6" trash can separator, and 15' of smooth pipe and 5' of flex should leave me with space to burn on SP.

But first I need to find parts or ways to put humpty dumpty together, hence the questions.

Fernco fitting are amde for different materials at each end. I would guess 6" copper, ABS, pvc or iron pipe. Or try 5.5" cast iron or clay. Asbestos pipe of " may work.
Fernco 1003 series is 6.00" for asbestos cement pipe. Or wrap the nipple with duct tape or electrical tape for several turns until it is a good fit into the fernco.
Your measurement is not clear. What is the outer diameter of you 6" outlet? Is it 6" or is it bigger?
Bil lD

https://www.fernco.com/products/flex...plings#tid-177

The 6" inlet does actually measure 6 inches. Orange and blue stores only had one 6" fernco, appears to be for PVC pipe to pipe as it is almost 7" ID.

When i had an issue getting a fernco over old cast iron in a trench I put a cherne plug into the fernco and expanded it for 30 minutes or so. Then quickly slipped it on and waited for the rubber to shrink back down before tightening the clamp. You could turn a cone to fit inside and pound it in to expand it I suppose.
Bil lD.

It might be because the impeller on my collector is only 12 inches. I don't dispute anything you've said. Dust collection and the air dynamics involved are intimidating to me. I'm going to do the best I can to piece something together, and hope it works well!

Quote:

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Originally Posted by Jay Kepley

It might be because the impeller on my collector is only 12 inches. I don't dispute anything you've said. Dust collection and the air dynamics involved are intimidating to me. I'm going to do the best I can to piece something together, and hope it works well!

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Ditto that!!

:rolleyes: Expand from 7" to 6"?

Quote:

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Originally Posted by Anthony Whitesell

That is interesting since the Onieda designed DC system that is too tall for me to install came with a 2HP motor 13.5" fan (IIRC) and 6" main ducting. It is Oneida's specialty, but i think some information waas relayed poorly. A carte blanche statement that a 2HP motor will not support 6" duct cannot be made. It is TOTALLY dependent on how big the system is (how much duct) and the fan curve. In my shop, the DC is centrally located with the longest run (for the table saw) being 20' maximum. Based on the spreadsheet from Bill Pentz, 6" inlet, 6" trash can separator, and 15' of smooth pipe and 5' of flex should leave me with space to burn on SP.

But first I need to find parts or ways to put humpty dumpty together, hence the questions.

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The maximum duct size is based on minimum air velocity in the duct, necessary to keep the dust/chips in suspension, rather than settling out in the ductwork. Once the dust starts settling out, it forms clumps, and when they get big enough to block enough airflow, they break loose and can damage and/or clog the system.

The actual air velocity depends on the blower, the duct size, length and configuration, and the efficiency of the filter and the separator.

It seems the wildcard here is the efficiency of the separator (not just how much dust it separates, but how much pressure drop it introduces). Conical cyclonic separators are the most efficient kind, especially compared to a trash can separator.

Therefore, simply because you have a blower, a filter and a duct length that supports 6" ductwork, you may not be able to support that duct size with a trash can separator.

Also, multi-drop ductworks can suffer from leaky blast gates reducing airflow from the open inlet(s), compared to a single non-branched run to the farthest point. Each Y fitting also adds pressure drop, due to the eddy flow in the blocked off branch.

-- Andy - Arlington TX