cyclone filter cleaning

[mreza Salav]

I have a Clearvue with the standard two cartridges. I noticed recently that the suction has dropped significantly and so I suspected the filters are to blame.
I do have a bin-full-sensor but typically by the time the warning light goes on there is about 10-20 inchs of shavigs at the bottom of the cone (when I'm in the middle of a planing job) which typically results in some shaving/dust going in to the filters (I would say about a few cups of shavings). Recently I did a lot of sanding (drum sander) and had about 40 gallons of very fine dust in the bin. Overall I think I have had easily over 1000 gallons (maybe much more) of dust/shavings gone through this system since new. So I took the filters out and tried to clean them. I don't have a good compressor so only vaccumed what I could from inside and shaked/tapped on the ground to get rid of some of the dust.

Is this normal to have to clean the cartrdige after this level of usage? I think I don't have leak in the system. I will check how the system performs.

comments/suggestions?

[Phil Thien]

Is this normal to have to clean the cartrdige after this level of usage? I think I don't have leak in the system. I will check how the system performs.

comments/suggestions?

Well if you're routinely filling the drum to the point where you have 10-20" of shavings at the bottom of the cone, then yep!

You need to keep shavings out of the bottom of the cone. Once shavings are filling the cone, the carry-over to the filters is going to increase dramatically.

Are you unable to see the warning light while using your tools? If so, perhaps you could reorient your warning light so it is easier to notice when the drum is full?

[mreza Salav]

Phil, the light sensor has 40 seconds or so delay (some delay is needed otherwise with every passage of material in front of it the light will come up). and it is located
at the lowest possible section of felxible hose between the cyclone and the bin.
Perhaps I should get a sensor with a different level of delay, but the thing is it doesn't take long to fill the bottom of the cone when you are planing a, say , 14" wide board
(a matter of 20 seconds or so I guess).

[Robert Payne]

The bin level sensor system that I make and market has about 15-20 seconds of delay from the onset of sensor blockage to a combined bright strobe/80 dB horn alarm. It also has a relay to interconnect the control box with the ClearVue Cyclone 240 VAC contactor. Finally, the unit includes a bypass switch that allows the user to continue operation of the dust collector while planing a board (as the OP indicated) and encountering a full bin (the strobe and horn are activated). A flip of the switch will immediately shut down the cyclone blower. The system has been installed on nearly 100 ClearVue and Oneida cyclones n the last two years. Contact me for details.

[Michael W. Clark]

Hi Mreza,
Been following your door build on the other thread, great work by the way and interesting project for sure.

Even without the drum filling up and into the cone, I would say you are overdue a filter cleaning. A cyclone is not 100% efficient, so some % of the dust always goes to the filters. Cyclones have a performance curve, the larger the particle, the more efficient, and vice versa. Therefore, only the small particles carry over to the filter and need to be cleaned periodically or they can become embedded in the filter where it cannot be cleaned, or otherwise known as "blinded".

Its best if you leave some room below the cone for the bin full level to prevent re-entrainment of collected dust. The vortex is very strong at the bottom of the cone and as Phil stated, carryover increases dramatically as the level fills.

Some on here have installed a filter pressure gauge (Dwyer magnehellic 0-5"wg range) to monitor filter pressure drop. This is the real indicator of when the filter needs to be cleaned and the effectiveness of your cleaning. Your airflow drops because of the increased pressure drop across the filter, so if you keep this pressure drop to an acceptable range, the airflow also stays at an acceptable range and you keep the filters working well.

Mike

[Tom Wassack]

I have a Clearvue with the standard two cartridges. I noticed recently that the suction has dropped significantly and so I suspected the filters are to blame.
I do have a bin-full-sensor but typically by the time the warning light goes on there is about 10-20 inchs of shavigs at the bottom of the cone (when I'm in the middle of a planing job) which typically results in some shaving/dust going in to the filters (I would say about a few cups of shavings). Recently I did a lot of sanding (drum sander) and had about 40 gallons of very fine dust in the bin. Overall I think I have had easily over 1000 gallons (maybe much more) of dust/shavings gone through this system since new. So I took the filters out and tried to clean them. I don't have a good compressor so only vaccumed what I could from inside and shaked/tapped on the ground to get rid of some of the dust.

Is this normal to have to clean the cartrdige after this level of usage? I think I don't have leak in the system. I will check how the system performs.

comments/suggestions?

Since you also asked about cleaning your filters, I'll share my technique used for an Oneida pro system. Before I leave the shop for the day, I use a compressor (a small pancake used for trim guns) and an air nozzle to blow the outside of the filter while still installed. I let this sit overnight to allow the dust to settle out into the clean out pan. The next morning I remove the pan and the filter and place the filter outside on a simple 2X constructed filter holder. I then fire up the leaf blower to a low-moderate air flow and blow the filter from first the outside and then inside. I repeat from the opposite end. I use a shop vac for the fine particulate in the clean out pan. Reinstall filter and pan and make sawdust and shavings.

Regards,
Tom Wassack

[mreza Salav]

Thanks for the comments. My basement doesn't allow me to have much room for the flex hose at the bottom of the cone. Hopefully when I move to a better shop I'll add more flex hose to help this.
Leaf blower is something I have and didn't think about it! I installed the filters tonight and the performance is much better. So the next time I'll keep this tip in mind.

[Sam Puhalovich]

The first time I had to clean my Wynn CV filters ... I sent a note to Wynn, asking 'how-to'. Response was to either use a blow-gun with 35 lb of air, or, use an old sneaker and lightly pound on it. The blow-gun routine was very slow, tedious, and not very effective. The sneaker was more effective, but, seemed never-ending. After a few hours I decided to quit and put-it-back-together. The suction was dramatically improved. Several months ago there was a thread about cleaning filters ... in place. I bought 2 10' lengths of 4" s&d & connected them to the clean-out with a piece of flex and vented to the outside. With the CV 'on' ... I used a shop vac as a blower ... with the hose plugged into the exhaust port ... and blew-out (in) as much of the surface area as I could present the hose to. The operation was relatively quick, and majorly effective, as I could see the clouds of dust billowing outside. The suction was very much improved ... more-so than the prior cleaning. While the shop vac 'exhaust' does not have a great amount of psi ... it moves a large volume of air, making it much more effective than a blow-gun.

[glenn bradley]

I have never cleaned my filter other than using the internal brush system in several years of use. I also have only once over-filled the bin and "full" to me does not extend into the neck of the flex hose, that's over-full ;). If you allow the bin to fill to where the hose is holding spoil, get used to cleaning your filters. I know you've put some effort into the bin-full sensor but, with that design not triggering until its "too late", it becomes more of an emergency signal than a normal "full" signal IMHO. If the bin is anywhere that you can see it I would be tempted to cut a slot in it and install a window so you can see when you are within a few inches of the top of the bin; that's "full" in my shop and as I say, I have not had to remove the filters for cleaning since I installed it in January of 2009. An "ounce of prevention" and all that. :)

[Rod Sheridan]

I clean my filter about once a year.

I bag it, take it outside and wash the inside out with the hose, works far better than compressed air.................Rod.

[Alan Schaffter]

Be careful using compressed air- you can permanently damage the filter media.

I use a combination of techniques. My filters are connected, side-by-side to a plenum. When it is time to clean the filters, I remove one and put a blank out over the hole. Then I put the filter on a small MDF pedestal which I connect with some flex to a spare blast gate. I turn on the DC which now pulls air from the outside to inside of the filter being cleaned. I help break the dust free with careful use of compressed air filter and the sneaker method. This cleaning method creates much less mess.

http://www.ncwoodworker.net/pp/data/1329/medium/P10100501.JPG

http://www.ncwoodworker.net/pp/data/1329/medium/P6290033.JPG

http://www.ncwoodworker.net/pp/data/1329/medium/P6290034.JPG