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smiley65

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Hi all i have just bought the axminster ac216ts table saw and they say use a 850m3 ph extractor but would a 183m3 ph do the job was looking at the scheppach ha1000
 
I think this is made for a proper large chip extractor, not a shop vacuum... But might be worth investing into the extractor, if you buy some more large tools eventually. Jointer, thicknesser, or band saw, to name few. I got this and it works great. If you fancy smaller and cheaper, this would be great. Just don't buy these with the bag. They are not good filtering systems.
 
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I have never used the Scheppach extractor you mention but think it would be okay with your table saw.

I use one of the oversize type shop vacs on my table saw and it works well (although it is a more powerful one).

Peter Millard seemed to quite like the Scheppach

 
If a sawbench needs 850m3 per hour a small extractor sucking just under a fifth of the volume isnt going to be adequate. At my last school the service provider had two shopvacs fitted to the sawbench. They were virtually ineffective & the sawbench spewed dust everywhere. You only get one set of lungs .
 
I'd go with Doug71...that table saw is relatively small. I use a Camvac with my table saw and suspect it is very similar in 'suck' to the Scheppach and works fine.
 
I have never used the Scheppach extractor you mention but think it would be okay with your table saw.

I use one of the oversize type shop vacs on my table saw and it works well (although it is a more powerful one).

Peter Millard seemed to quite like the Scheppach


Thanks doug thats the one i was thinking of getting because i have a 12x8 shed and most other units would need a shed on there own
 
That's the model I've been looking at but I'm slightly puzzled as to why it has a lower rated airflow (1390m3/h) than the similarly sized 1.5kw AC153E (2000m3/h) and even the 1.1kw AC82E (1530m3/h)?

The AC118CE has an integrated cyclone extractor, while the AC153E and AC82E do not. The cyclone reduces the airflow in the system, but in my opinion is a better option than passing all material through the fan.
 
The cyclone reduces the airflow in the system, but in my opinion is a better option than passing all material through the fan.

Does it really reduce suction by over 30%? And what's the advantage of not having everything go through the fan? Not challenging your opinion, I really don't know but want to understand.
 
Does it really reduce suction by over 30%? And what's the advantage of not having everything go through the fan? Not challenging your opinion, I really don't know but want to understand.

There's no problem challenging my opinion, as I always reserve the right to be wrong. 😊

I don't know what the actual reduction is and don't put a lot of faith in the manufacturer's claims of airflow. I've never baselined my dust collection (DC) system without the cyclone, but when modify the system later in the year, I will consider measuring the airflow of the fan alone before I install the new cyclone and larger ducting. I made rookie mistakes in my DC design, which I will try to correct later.

From what I've read, some manufacturers base the fan airflow at the inlet of the fan with no restrictions on the output, such as the filter or collection bags, while others do not identify the conditions when the measurements were made. There are too many variables in a dust extraction system, such as duct cross sectional area, length of ducting, number of bends in the ducting, fan diameter, fan width, motor size, and so on. The best source I know of to learn how to navigate the dust extraction minefield is the Bill Pentz Dust Collection Research website. There is a lot of information on Bill's site, and is it a great starting point, even though it can be a difficult read.

The advantage of the dual-stage system, whether it is a cyclone or Thien separator, is the majority of the collected material loses velocity and drops into the collection bin. Very little passes through the fan and onto the filter. In the single-stage systems, such as the AC153E and AC82E, everything passes through the fan before reaching the filter and bag. Over time, dust will collect on the fan, which can reduce airflow efficiency. Also, chunks larger than shavings or dust can damage the fan blades.

In my DC system, the only times I have ever seen a buildup in the filters is when I let the collection bin fill up or had a leak in the seal between the collection bin and cyclone. In normal operation, very little dust makes it past the cyclone and the blades on the extractor fan are clean. After nearly a year of use, my filters are clean, but when the cyclone stops working because of the two reasons I mentioned, the filters fill up quickly and the fan blades accumulate a coating of dust. This always requires a complete teardown to clean the filters and fan. Lesson learned.
 
Does it really reduce suction by over 30%? And what's the advantage of not having everything go through the fan? Not challenging your opinion, I really don't know but want to understand.

The cyclone does have internal drag just like ducting, fittings and hoses. Best cyclone will loose about 2" of water column of the suction. A poor design or a can separator can loose two or more times that.

The way DCs are tested needs to be known. They strip everything off the impeller housing, inlet fitting, outlet adaptor to the hose, filters etc, leaving just the housing, fan and motor. A short test duct is attached to the inlet and they take the highest reading they can get from the middle of the airstream where the flow is fastest and then round up the number so it looks good in the specifications and advertising. Much like horsepower used to be reported for muscle cars. When everything is put back on you can expect about half the flow. With the cyclone being part of the impeller housing it would be part of the test.

Something you should be looking for is the particle size of the filters. The cyclone has a 1 micron filter. The two with bags are 30 micron. The fine dust you can't see in the air unless specially lit that causes most harm because it goes deep in your lungs is 10 micron and smaller. The cyclone will get most of it where the other two DCs pass the dust through the fabric. The impeller also minces up some of the dust into finer particles making it worse, hence the nickname in some circles as dust pumps.

Something else to know is that 100mm pipe can only flow about 680m3/hr, the 125mm flows about double and 150mm flows triple. So no matter how big the collector is you won't flow any more air than the duct size you are using. Longer ducts, flex hose, more elbows etc, machine restrictions you hooked up to reduce the flow too.

So in short the cyclone is the best of the three although you don't want to use long runs as it is marginal. The two dust pumps are not a good idea.

Mike covered some of what I said but I'm not going to edit it out. I also recommend Bill Pentz's site even though it is a long hard read. Start at the beginning and read it all, even the repetitive stuff.

Pete
 
That's the model I've been looking at but I'm slightly puzzled as to why it has a lower rated airflow (1390m3/h) than the similarly sized 1.5kw AC153E (2000m3/h) and even the 1.1kw AC82E (1530m3/h)?

As said above, you will lose some performance with the cyclone, but you also gain other benefits that are worth the trade in my opinion. I've not yet extensively used my extraction, only emptied it like 3 or 4 times..? But I did not find any dust in the bag under the filter at all. So I pretty much expect very very long life of the filter, if I never forget to empty the bin under the collector. So the effectivity of the cyclone is beyond question, even at some suction loss trade.

BTW I have modified mine to get more capacity and reduce the hustle of bag installation. Just too annoying to use often.
 

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I think this is made for a proper large chip extractor, not a shop vacuum... But might be worth investing into the extractor, if you buy some more large tools eventually. Jointer, thicknesser, or band saw, to name few. I got this and it works great. If you fancy smaller and cheaper, this would be great. Just don't buy these with the bag. They are not good filtering systems.
Hmmm... Smaller and cheaper is important to me. Following recommendations elsewhere, I HAVE bought one of "these with the bag". I have set it up with a Thien baffle cyclone - and (in summer) it exhausts outside.
I am curious. "this would be great" looks so similar tho the working part of "don't buy these" - same wattage - but one only pulls 850m/hr and the other one 1000m/hr. I have connected mine to some ducting and I have to say that the suction is pretty pitiful. Is it the baffle that is killing it?
 
I used to have a similar type of extractor to the scheppach, it fills up annoyingly quickly the barrel is mostly filled with the large central filter. I would suggest something like the record dx500 or a camvac with removable bags.
Or a seperator barrel with cyclone at least.

Ollie
 
Hmmm... Smaller and cheaper is important to me. Following recommendations elsewhere, I HAVE bought one of "these with the bag". I have set it up with a Thien baffle cyclone - and (in summer) it exhausts outside.
I am curious. "this would be great" looks so similar tho the working part of "don't buy these" - same wattage - but one only pulls 850m/hr and the other one 1000m/hr. I have connected mine to some ducting and I have to say that the suction is pretty pitiful. Is it the baffle that is killing it?

The pitiful suction is due to a few factors. Firstly the 100mm duct/hose is limiting flow (said that above) next is the optimistic flow claims (said that above) lastly is the baffle separator (said that above too but called it a can separator, same category).

Axminster doesn't show the static pressure losses nor a fan curve (which would show the flow in relation to the static pressure). I looked a Grizzly and theirs is 7.2" of water with zero flow. That means the inlet completely blocked. As soon as the duct gets opened the static pressure will drop as more air is allowed to flow through. When wide open there is probably 2" or 3" at best of static pressure. When you add the baffle, duct, hose, elbows etc each takes away from that 2" or 3" of flow eating away at the air flowing into the duct. In other words you have pitiful suction. You'll have to convert the water column to metric it you relate to it better.

When your duct is vented outside you have a little better flow but more importantly the dust is out of the shop, at least what gets captured is. When you use the bag it is letting most of the fine dust through for your lungs to enjoy. You should be wearing a good mask all the time, especially when using the bags and for at least an hour or two after.

Pete
 
Hmmm... Smaller and cheaper is important to me. Following recommendations elsewhere, I HAVE bought one of "these with the bag". I have set it up with a Thien baffle cyclone - and (in summer) it exhausts outside.
I am curious. "this would be great" looks so similar tho the working part of "don't buy these" - same wattage - but one only pulls 850m/hr and the other one 1000m/hr. I have connected mine to some ducting and I have to say that the suction is pretty pitiful. Is it the baffle that is killing it?

The main advantage here is the canister filter. It let's more air through, due to larger surface area, but also filters better. It's literally win win... At least when talking bag vs canister filter.
 
Hi all i have just bought the axminster ac216ts table saw and they say use a 850m3 ph extractor but would a 183m3 ph do the job was looking at the scheppach ha1000

The quoted figure refers to LPHV system - the HA1000 is a HPLV system and you can't really compare them directly using airflow volume. To answer your (OP) question: yes, the HA1000 is fine. How do I know? I use the HA1000 with my AC254TS and my Sabre350, Laguna Drum Sander, DW Thicknesser and Axminster Spiral Head Surface Planer. I've used it for years without the smallest issue. TBH I do get jams on the thicknesser when processing maple/sycamore, but that is at the thicknesser end and I suspect that would happen with a LPHV system too.
 
I agree with @Chris Hawkins above about the difference between HPLV and LPHV.

I have a Record DX 4000 connected to my panel saw which is one of the HPLV dustbin type shop vacs which claims to move 381m3/hr and it works well.

I also have a LPHV bag over bag type Jet extractor which claims 1,100m3/hr on a 100mm pipe which is connected to my PT.

When you compare them side by side the Record definitely sucks harder despite the much lower rating.
 
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