Dust Collection Adventures

[DWSmith]

I have been fighting a problem with dust caking the inside of my filter on the Oneida Pro 2000 I have installed in my shop. So as not to bore the reader with prior details, I decided to eliminate the dust before entering the DC. I first tried a Thein separator which worked reasonably well but I still get a lot of dust caked on the inside of the filter. Thinking maybe the separator wasn't all I had hoped for I bought a Super Dust Deputy from Oneida. It was delivered this morning.

I was a little let down with the construction when I saw the inlet and top outlet were simply caulked in to place and not welded. (I could see light through the caulk from the inside.) The main seam from top to bottom was spot welded and the seam around the top looks as though it is caulked into place as well. The mounting flange at the bottom looks to be welded. So I took my time and set it up correctly, making sure all the joints were covered with gasket material and everything was bolted tight.

Prior to starting using the Super Dust Deputy, I removed the filter from the Pro 2000 and blew it out with compressed air so it could be as clean as possible. Once reinstalled and started, I marked the pressure gauge to see where it was. After 1.5 hours of sanding on my double drum sander, I can state positively the Super Dust Deputy is no better, and maybe a little worse, at removing dust than the homemade Thein separator I just removed. The pressure gauge moved from a .2 to a 2.2 in the hour which means a lot of dust has made it way through the Super Dust Deputy and the main cyclone into the filter and it is on its way to being clogged up again.

I hesitate to call Oneida since all I get from them is "You have a pin hole leak somewhere".

I have a friend who has a large CNC with a MDF table top. His vacuum has enough suction to hold work down with vacuum pressure through the MDF. If the CNC can produce enough vacuum pressure through MDF, could my fiber barrel be porous enough to break the vacuum inside of it slightly enough to cause the leaks? Interesting question. Any ideas?

 

[CarvedTones]

The fiber barrels I am familiar with have a tough plastic liner. Yes, I think it would leak like a sieve without one or if it were damaged.

 

[BillPappas]

I always put a super heavy duty construction trash bag in the fiber barrel. I was not a production shop like yours and would routinely tap the filter to prevent caking and I did not have issues with my Dust Gorilla.

 

[DWSmith]

I did call Oneida again this afternoon and explain my problems to a rather nice young lady. She promptly gave me a RMA for the Super DD and promised to have one of the Senior Technicians call to discuss the problems. The call was at 2 pm just after I posted the first entry. No call yet. We'll see if they actually will call.

 

[Bill Clemmons]

David, I look forward to following this thread to see if you are able to solve the caking problem. Cleaning the filter on my Onida is a real pain. Overall though, I've been very satisfied w/ the performance of the DC. Let us know if you ever get it resolved.

Bill

 

[MarkE]

Try an experiment David. Leave 1 or 2 additional blast gates opened as well as the one to the machine you are using. I have one 4" gate that is always open along with a 4" or 6" gate going to the machine in use. It seems like the extra airflow going into the cyclone helps get things separated better so they fall into the collection drum faster.

My Super Dust Gorilla has an 8" inlet so I would guess it doesn't really work as efficiently when it is trying to suck through a 4" pipe. You can actually hear the difference in the sound of the cyclone motor when more gates are opened allowing for more air to flow into the cyclone. It sounds happier.

 

[Vetteman9956]

David, this thread is of real interest to me as I also had the same unit arrive today, I have not had the chance to install it so I can't voice my experience yet. I am using a plastic drum so we will see if that works better.

 

[eyekode]

Mark,
In David's original thread where he tried out the Thein separator we went over lots of possibilities. And we proposed opening additional gates to get the air speed up. But David mentioned he always has extra gates open.

David,
I don't remember: did you try to put your collection bin in a trash bag? I have heard this can help find leaks. Get the biggest/strongest trash bag you can and place your collection bin inside it. Then tape the top of the bag to the cyclone in an air-tight manner. If you have a leak the bag will collapse. If it doesn't collapse you don't have a leak.

Best wishes,
Salem

 

[DWSmith]

Thanks again guys. I do keep all the blast gates open, 4" at the planer, 4" at the jointer, 4" at each of the two cabinet saws and a 4" at the drum sander. As for a plastic bag inside the fiber barrel, I don't have any large enough. So the plan is to get a 55 gallon plastic barrel tomorrow and try it out. Maybe by this time tomorrow I will know if the fiber barrel is air tight or not.

eyekode - I might just try this bag test tomorrow if I can find a bag large enough. Thanks.

 

[ehpoole]

David,
I don't remember: did you try to put your collection bin in a trash bag? I have heard this can help find leaks. Get the biggest/strongest trash bag you can and place your collection bin inside it. Then tape the top of the bag to the cyclone in an air-tight manner. If you have a leak the bag will collapse. If it doesn't collapse you don't have a leak.

The bag will do far more than collapse, it will INVERT! (DAMHIKT) Just make sure the bag is incredibly well secured to the canister or it will be sucked *through* the impeller assembly, and then you will have a mess to clean up.

Just remember, if it is a pinhole leak it may take a good while before the bag inverts, and the faster the inversion the greater that leak. Also be on the lookout for any air leakage around the rim of the canister.

This is why most DC's that are meant to support waste bags in their collection bins also run a vacuum line to the waste bin to insure that any air leaking into the space between the bin and bag is removed quickly and not allowed to accumulate. The vacuum line may either be supplied by a small vacuum pump (similar to an aquarium air pump) OR to a portion of the DC that is either at a lower pressure OR which can generate an adequate venturi effect to draw down the pressure.