(HVLP) Extractor + down draft table.

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Eamonn

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I have a (HVLP) Extractor which, I've read, aren't good for fine dust.

I was thinking of using it in a down draft table, table saw, router table "All in One" table. With the (HVLP) Extractor as the main suction. I'll probably add a shop vac in there too, but want to find out if a cyclone + (HVLP) Extractor will work with a downdraft table.

Also I plan to make a Mitre Saw station with a hood at the back for dust/chip collection. I know a shop vac as close to the source as possible will work, but what about a (HVLP) Extractor for the whole hood?

What are peoples thoughts on this all? Thanks.
 

Inspector

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How big a HVLP cyclone are you talking about? The downdraft tables where I worked were 5hp and supposedly 3,000CFM through 4 cartridge filters (1,000 sq ft). The tables were 4'x8'. The ClearVue Cyclone with a 16" impeller at 60 hertz will move two thirds of that so any 1 or 2 hp dusty is not going to be very effective. Try it if you want to satisfy your curiosity and tell us what happens.

HVLP collectors are good for fine dust but you need 6" ducting, a minimum 3hp (more if using a cyclone too) driving a 14" impeller, and you have to open up your machine to allow the air to flow through. It's a long read but here is the information. Dust Collection Research - Home

Pete

Just noticed this is your first post. Welcome to the forum.
 

Eamonn

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How big a HVLP cyclone are you talking about? The downdraft tables where I worked were 5hp and supposedly 3,000CFM through 4 cartridge filters (1,000 sq ft). The tables were 4'x8'. The ClearVue Cyclone with a 16" impeller at 60 hertz will move two thirds of that so any 1 or 2 hp dusty is not going to be very effective. Try it if you want to satisfy your curiosity and tell us what happens.

HVLP collectors are good for fine dust but you need 6" ducting, a minimum 3hp (more if using a cyclone too) driving a 14" impeller, and you have to open up your machine to allow the air to flow through. It's a long read but here is the information. Dust Collection Research - Home

Pete

Just noticed this is your first post. Welcome to the forum.
Hi,

my extractor is a Axminister one, (Light Trade) that I bought 10 years ago and never really used it, so was thinking to put it to use. It does 850 m3/hr. All

For the Cyclone I was going to use three of those small generic white plastic ones (they are around 350mm high). All three on top of the collection bin. The reason for small cyclones is I'm trying to get this all in/under the bench. The extractor will be very close to all collection points so there will be minimal ducting.... Which leads me to another question...

Can those extractors be mounted sideways?

My extractor looks similar to this one. Exact same configuration/layout.

1653095226033.png
 

IBmatty

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As long as the inlet and outlet are pointing where you need/want them too, mount however you like.
 

Sideways

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I think if you add cyclones to your style of extractor you'll kill what little suction it has.
I've played with a big axminster trade extractor with cyclone, cartridge filter, etc and the airflow wide open was awesome, as soon as you start connecting the fine fine filter or the cyclone and then both, the airflow drops dramatically. Even worse if you then connect undersize pipe or hose.
Those fans move air but just don't make good suction. You need full bore pipes, few bends, etc.
A bunch of cyclones will reduce it's suction by about 25%, even if you match the total inlet size to the extractor (and for that you will need four 50mm inlet mini cyclones if the axminster has a 100mm inlet).
A downdraft table doesn't have to swallow a great deal of dust, better to use it as it is.
 

Inspector

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Re the 850 m3/hr claim. Manufactures test impellers without any ducting or filters attached. I real life when the filters and ducting/hose is added the flow will be about half the advertised.

Trying to make a shop version of a Dyson won't work like you think. The multi cyclone setup in a vacuum cleaner works because it is a High Pressure Low Volume (HPLV) setup where you have 80" to 140"of water/20,000 to 35,000 pascal. Your High Volume Low Pressure (HVLP) collector operates in the 4" to 6"water/1,000 to 1,500 pascal range. It can't overcome all the drag of the little cyclones.

Pete
 

Eamonn

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I think if you add cyclones to your style of extractor you'll kill what little suction it has.
I've played with a big axminster trade extractor with cyclone, cartridge filter, etc and the airflow wide open was awesome, as soon as you start connecting the fine fine filter or the cyclone and then both, the airflow drops dramatically. Even worse if you then connect undersize pipe or hose.
Those fans move air but just don't make good suction. You need full bore pipes, few bends, etc.
A bunch of cyclones will reduce it's suction by about 25%, even if you match the total inlet size to the extractor (and for that you will need four 50mm inlet mini cyclones if the axminster has a 100mm inlet).
A downdraft table doesn't have to swallow a great deal of dust, better to use it as it is.
Yeah I think I will use it as is and have a few shop vacs and Cyclones for the Router table and table saw.
 
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