Thread: Metabo ASR 2050 vacuum - the bad news

Originally Posted by jefferson

I have two of these machines and hook-up directly to a number of hand-held sanders and routers.

Yesterday, my mate replaced a full paper bag filter, then hit the R button, which vibrates the secondary filters clean. Not my usual routine. The amount of fine dust dumped was incredible - I just wonder how much of the even finer dust is escaping while I'm sanding etc.

I will use that commonly used highly quantitative term, i.e. "LOTS"

Like DCs all VC also leak, so unless it is inside an air tight container that is vented outside or place outside the shed they will eventually fill a shed with invisible dust.

Thanks, Bob.

I think I already knew the answer but I still need a solution. My shed is 25m long, so sticking the VC outside is problematic. What if I ran the VC under various hoods from my cyclones that will vent outside?

I don't want to hijack the thread but is there any vacuum made by anyone that doesn't leak or masticate the dust into finer particles? Laboratory, industrial or maybe hospital?

Jeff perhaps rather than a hood over the vacuum, putting the vacuum in a box that is hooked directly to your cyclones. With the incoming air opening over the Vacuum's cooling intake and hopefully let you easily reach the switch through the hole. The exiting air opening into the cyclone at the vacuum's cooling exhaust. Just an idea but better see if Bob will endorse the concept.

Pete

Originally Posted by jefferson

Thanks, Bob.

I think I already knew the answer but I still need a solution. My shed is 25m long, so sticking the VC outside is problematic. What if I ran the VC under various hoods from my cyclones that will vent outside?

25m is not a problem for VC ducting,
if you use 2" ducting the pressure loss will be ~8" of WC.
A good DC should generate 25 - 30" of WC so if you lose 9" of pressure its not that big a deal.
If you can place the VC at the halfway mark outside the shed along the long axis and duct down that side of the shed, most of your shed can be covered using significantly less than 25m of ducting.

Originally Posted by QC Inspector

I don't want to hijack the thread but is there any vacuum made by anyone that doesn't leak or masticate the dust into finer particles? Laboratory, industrial or maybe hospital?

At work we investigated VCs about 10 years ago and found we had to spend $$$$ to get one that filtered the motor cooling loop to prevent the minced dust by the motor escaping the VC. Initially we purchase one of these http://www.terrauniversal.com/cleani...m-cleaners.php but it does not filter the motor cooling loop and would be too small for a workshop. A similar version to the one we eventually purchased is this one (http://www.terrauniversal.com/cleani...rs-economy.php and I see the price is ~US$4k. If you look at the VCs on that site you will see that, even though these VCs are working in a much more gentle environment that a workshop, they are mostly more ruggedised than domestic/workshop VCs.

The reality is that any DC or VC that is made of plastic and is towed around, tripped over and has things dropped on it in a shed would have to be built like a brick outhouse to withstand that sort of treatment. To add to that the seals dry out, get jammed, damaged etc. The seals should be replaced every couple of years and the motor cooling loop should be cleaned out using compressed air (preferably outside the shed .

All of the VCs I tested (even very expensive ones) that had been used in very dusty sheds and were more than about 5 years old had problems and in my opinion should have been probably just be thrown away or located outside a shed. To keep a VC from becoming contaminated it should not be used in a dusty environment but that kind of defeats the purpose of having one.

The only way to be sure workshop DC or VCs are not leaking or dirtying the air in a shed is by regularly testing it (e.g. once a week and every time it is emptied). While this can be done with a relatively low cost Dyloss particle counter, proper testing takes time because budget level particle counters are not sensitive enough to pick up low concentrations of fine dust and so take time to make an accurate measurement. Even expensive particle counters take time to use properly .Besides who wants to spend time testing VCs and DCs - wouldn't we rather be getting on with something else. This is why it is just easier to put everything outside.

Jeff perhaps rather than a hood over the vacuum, putting the vacuum in a box that is hooked directly to your cyclones. With the incoming air opening over the Vacuum's cooling intake and hopefully let you easily reach the switch through the hole. The exiting air opening into the cyclone at the vacuum's cooling exhaust. Just an idea but better see if Bob will endorse the concept.

Yep better than nothing (especially if you cannot put the VC outside) but as the enclosure will be under pressure it too may leak so you may be back to square one.

Thanks for taking the time to reply and put up the links Bob. Disappointing to say the least that a money's no object machine still is far from perfect.

One thing you said at the end though has me a touch puzzled.

"....as the enclosure will be under pressure...."

If the enclosure (sealed box) holding the vacuum is hooked to a outdoor vented cyclone, presumably with a 6" / 150mm duct, wouldn't it be under negative pressure to some degree? With a vacuum pulling in 100 to 200 CFM into the box and the dusty pulling 5 to 10 times that amount out with the right sized opening to making up the difference, would there still be a dust escapement issue from the box and the vacuum inside it?

Pete

Originally Posted by QC Inspector

Thanks for taking the time to reply and put up the links Bob. Disappointing to say the least that a money's no object machine still is far from perfect.

One thing you said at the end though has me a touch puzzled.

"....as the enclosure will be under pressure...."

If the enclosure (sealed box) holding the vacuum is hooked to a outdoor vented cyclone, presumably with a 6" / 150mm duct, wouldn't it be under negative pressure to some degree? With a vacuum pulling in 100 to 200 CFM into the box and the dusty pulling 5 to 10 times that amount out with the right sized opening to making up the difference, would there still be a dust escapement issue from the box and the vacuum inside it?

Pete

Sorry - in that case you are correct.

Thanks, guys for helping with this. I am spending Father's Day cleaning the shed out and will post some pics tonight. The two cyclones will be inside, but vented outside. Bob, still not clear on what you are telling me to do with the 2 Metabos. I frequently fax up in the turning end of the shed, in the middle where all the machines are, and soon in the far end where I will set up my main workshop. All ideas appreciated, undergoing a major re-fit at the moment.

Originally Posted by jefferson

Thanks, guys for helping with this. I am spending Father's Day cleaning the shed out and will post some pics tonight. The two cyclones will be inside, but vented outside. Bob, still not clear on what you are telling me to do with the 2 Metabos. I frequently fax up in the turning end of the shed, in the middle where all the machines are, and soon in the far end where I will set up my main workshop. All ideas appreciated, undergoing a major re-fit at the moment.

Sorry I was not clear. What I was saying was a 25m long shed should not be a worry to duct for vacuum use. Putting the VC outside the shed and using 2" ducting around the internal walls with a port every 5 m or so should allow you to cover most of the inside of the shed with a shorter length of hose.
If you wanted better performance you could have the VCs outside at each end of the shed.

Bob, you are a top fellow.

The fact is that I have too many machines. This afternoon the wife and I tried to fix the mess in the turning end of the shed, sorry no pics. I am very concerned about the fine dust. And how to evacuate it from the shed. When the sunlight pours in, you can see it, never mind the finer stuff.

$ are not in issue. I'm about to fit 2 cyclones for the shed and I suspect I will not get I right. I nose bleed turning redgum, the kind of pain you suffer with X.

My "solution" is to turn the swampy on and send all the dust outside. Not nice when I can see the snow from my block.

I turn, route, saw all kinds of wood. And need an answer. Sand on the lathe - how to get rid of it. Domino mortices, same thing.

It's a bugger, not short on $ but a solution.

It is virtually impossible to eliminate all dust unless you turn your shed into a "clean room", the simplest way to combat the fine dust to to use one of the various masks or respirators that are on the market