Thread: How to Clean 1micron Pleated Filter Cartridges?

I cleaned mine with compressed air while still on the unit -seems OK. A large amount of dust fell into the bag

There are companies that wash filters so maybe try one of them. Most people just hit them with their hand or something else to loosen the debris and let it all fall to the bottom bag etc and it seems to work for them. Just how much it works is another question altogether. The ultimate answer is not to use filters and get the dust extractor isolated from the work area to enable you to do just that. One micron filters still allows a lot of the deadly stuff through. Here is the way Clearvue catch the dust from filter cleaning....

CV1800 LH - Single Phase with Filters - Clear Vue Cyclones

Note the clean out box at the bottom of the filter stack. I have got some coming in a shipment but up until now have not seen one. As a rule installations in Australia have not used filters just exhausting straight to atmosphere. The only reason I have some coming is one customer has ordered six cyclones with filters and clean out boxes.

Originally Posted by Mini

The ultimate answer is not to use filters and get the dust extractor isolated from the work area to enable you to do just that. One micron filters still allows a lot of the deadly stuff through.

And wouldn't no filter let more through?

Of course, that is why it must be isolated from the workshop with no chance of the dust re-entering. Anyone who places a single stage extractor (bag type) in a workshop where they are working is simply recycling the dust and wasting their money. All they have done is saved themselves the problem of sweeping up the shavings as the finer stuff which is what gets trapped in the lungs is allowed to re-enter the work area because the bags are useless for trapping the finer particles. Anyone who buys a filter to replace the bag has only trapped down to a maximum of one micron but usually it is five microns, again wasting money. We need to face facts that for any single stage extractor to work within their limitations they need to exhaust to the atmosphere in such a way as to prevent that exhaust getting back into the workshop. Most of the smaller extractors have not got the performance capacity to even do that properly, 3hp should be regarded as rock bottom. BTW a good cyclone will separate down to .5 microns before the exhaust.

Originally Posted by Mini

. . . . Most of the smaller extractors have not got the performance capacity to even do that properly, 3hp should be regarded as rock bottom. BTW a good cyclone will separate down to .5 microns before the exhaust.

The "good cyclone" terminology may need clarification as some folk may consider a good cyclone as something they can make out of a 20L plastic bucket and a couple of pieces of PVC pipe hooked up to a 1HP DC whereas I think you mean a professionally designed cyclone with a 5 HP impeller that meets Bill Pentz KPIs. The focus should in fact not be on HP, but on the minimum air flow KPIs Bill Pentz promotes, which are 1000 cfm at 4000 fpm.

These KPIs are even just possible with a well made 2HP DC (i.e. has 6" in and out takes) provided it uses a short run (~3-4 m) of 6" ducting, very well maintained filters/bags, uses a very short piece of flex, and connected to only one machine that has well designed ports to permit the necessary airflow. All of these requirements, especially the last are rarely met. The problem with such a short ducting run is that unless the machine is up against a shed wall there is little chance of getting the DC outside the shed within this ducting distance. About the only alternative left is to build the DC into a cupboard inside the shed near the machine and use large area (e.g. 1 ft^2 (even wooden) ducting to the outside.

With a well made 3HP machine the KPIs can can be maintained for longer (~10m) of 6" ducting. Once again minimal bends, only one machine with well made ports can operate at any one time, and well maintained bags etc are essential to maintain these KPIs.

A 5HP professional system allows users to utilise 8 or even 9" ducting which means even longer ducting runs, the operation of several machines, and filters or bags can be allowed to load up more than usual etc. A cyclone itself does nothing directly in terms of the KPIs. What it does is indirect in that it protects filters from loading up faster than would otherwise be the case so the KPIs can be maintained for longer. A really big advantage of a professional cyclone is that in situations such as venting outside a shed, it may be possible that no filters at all are required. This means the KPIs can be effectively maintained indefinitely because there are no filters or bags to clean. of course no filters can mean some noise escapes from the system so some noise abatement may be required.

As I have said before, very few ClearVue cyclones in Australia use filters. The exception to this is in special industry requirements that we are just moving into that are not woodworking related. As far as the general hobbyist/woodworker goes we have sold three sets of filters in total and one of those was because the unit was being installed in an aircraft hanger, again a special requirement.

The need for filters that are used overseas is all driven by the need to recycle the air due to climate conditions and in a lot of case the workshops are in basements which makes it difficult to vent outside. No one over there wants to dump heated air outside the building which is understandable.

As Bob points out no filters equals no loss of performance and it also means the unit exceeds the performance quoted with the filters which is a plus.

I've only done it once in 6 years. I used a brush and it did the job very well.

Originally Posted by Mini

. . . . As Bob points out no filters equals no loss of performance and it also means the unit exceeds the performance quoted with the filters which is a plus.

It would be really useful to know what the air flow specs are without the filters.
Could you measure the air speed at the exit for a working system?
If not and you have you sold one in WA and the client would allow me I would be happy to go measure it.

At what fan speed and what size impeller? Some users run the bigger cyclone at 2850, one at 3450. The same with the smaller cyclone though most run them at 3450. I have run mine as high as 3950 to see if it blew up but nothing happened! I will measure mine at 3450 as soon as I can but I tripped over the dog last night and the my back is a bit dodgy at the moment.

The different speeds come about due to a couple of things. The US power supply @ 50hz means the motor runs at 3450 RPM. It must have been about the time that the original owners of CV (Ed Montagno) made overtures through this forum to export some units to Oz that it was realised that our 60hz power supply gave a motor speed of 2800 rpm. To overcome that Bill Pentz specified a 16" impeller against the original which was 15" and so the two different models came to be. This effectively negated the lower motor speed and raised the airflow back to at least the same as the 15'' fan but it is I think greater than that.

The yanks being the Yanks saw that bigger was better and started using it in the US at the greater fan speed and got far more usability out of it as multiple machines can be run at once. When we first looked at the idea of importing to Oz and setting up here on a permanent basis the issue of using the Leeson motor came up as it could only be supplied as 110 V single phase, no good to us, or 220 V three phase. After scratching my head and getting nothing but splinters for a while I came up with the idea of using a VFD to utilise the three phase Leeson and it has been a success. This actually makes the unit more flexible in operation as the speed can be varied as required. To give an illustration I vent my sons kart exhaust through it at a lower speed when tuning the motor! Seriously what it does do is enable us to run the motor at the designed speed so we retain the designed performance. What it can be good for is scrubbing the air after work is finished. The VFD gives us flexibility such as programming the VFD for a slow ramp down, leave some blast gates open and the cyclone will slowly reduce speed and clean the air while slowing down over a long period of time. for this reason I recommend a couple of open ducts not connected to the machine but that all except one can be closed while the working that one still scrubbing the air. After work open more and walk away but make sure some doors or windows are left open to supply the air. The cyclone will be run down and stopped by the VFD, look no hands Mum!

Originally Posted by Mini

At what fan speed and what size impeller?

It doesn't matter. It would just be interesting to know what effect the filter has, so flows with and without a filter is all that would be required.