Extractor run length

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Mrs C

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Are there any guides, rule of thumb or otherwise, re the max length of extraction hose vs power of chip extractor?

I want to hook 2 machines up to the same extractor but they will be opposite sides of the workshop.

Thanks
 
I think you'll find the following useful.
The internal rotation of the suction force multiplied by the hose diameter and then subtracting the hose thickness, then using the lower differential of the law of chip weight should give you some idea that I just can't help you with this question. sorry.

But if you run them independently you could put a gate in the pipe system to switch from one to the other.
Or contact the manufacturer for advice.
 
Take a look at this. It gives a gen rule of thumb based upon extractor power.
Just check your extractor power.
Good luck.
 
20210407_185114.jpg
 
Rule of thumb says shorter, straighter, better.
I just have a loose flexi tube which I connect as needed - only takes a few seconds. If necessary can extend by adding a length of plastic drainpipe to a join in the middle of the flexi pipe.
Maybe for your 2 machines have a fixed pipe to midway and a flexi pipe from there, swapping it between machines?
 
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Maximise diameter wherever you can (don’t exceed the inlet diameter of the extractor). Minimise length and changes of direction, use pipe over hose.
That’s about all there is to it.
Aidan
 
That video can be very wordy. In simple terms you have the "Hoover" with a small bore pipe that works on higher pressures but less flow and then the dust extractor that has a bigger bore pipe which works on lower pressures but higher flows.

All I use is a 50litre SIP extractor and connect it to the machine I am using, but for my mitre saw I use a Nilfisk hoover that is more than adequate.

I will also wear a mask and eye protection which as I am the only person using the tools is fine because there is no one else that can be affected by any dust.
 
my day job is as a particle technologies dealing with particles and airflows for industry. In this situation I would move the extractor to the tool, maximise the diameter of pipe, minimise the length and avoid any bends. A 1m hose straight to tool with extractor on wheels is a far better performing solution than a 10m run of hose across the workshop. I would not ask what the maximum length of hose is that could be used but how do I maximise my system performance. Aldi currently have a circular platform on wheels (plastic for £15) that is great for attaching many extractors directly or via a middle board and is very mobile. The process of swapping over hoses can be really quick with the right sort of (quick release) connector. Performance using this system would be great.
 
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my day job is as a particle technologies dealing with particles and airflows for industry. In this situation I would move the extractor to the tool, maximise the diameter of pipe, minimise the length and avoid any bends. A 1m hose straight to tool with extractor on wheels is a far better performing solution than a 10m run of hose across the workshop. I would not ask what the maximum length of hose is that could be used but how do I maximise my system performance. Aldi currently have a circular platform on wheels (plastic for £15) that is great for attaching many extractors directly or via a middle board and is very mobile. The process of swapping over hoses can be really quick with the right sort of (quick release) connector. Performance using this system would be great.
Agree. Moving the extractor, or merely reconnecting the one pipe, can be highly efficient. Simple push fit connectors can be connected in seconds.
A maze of plumbing with several flexi connecting pipes trailing all over the place is inherently less efficient, can take up a lot of space and get in the way of things, completely defeating the object.
 
maze of plumbing with several flexi connecting pipes trailing all over the place is inherently less efficient, can take up a lot of space and get in the way of things, completely defeating the object.

It's not till you've been there and done it do you realise that. It's something we all go through I think.
 
Sounds like you have had a lot of good advice already, another advantage of keeping the unit mobile is being able to empty it in the fresh air, there is no point in storing the dust to breath it later, even in industrial use you would be surprised how many people empty a system by turning the bin upside down into a barrow etc. and create a great cloud of dust for everyone to breath. I used to inspect extraction systems and have seen a lot of issues with complex commercial units where a lot of money had been spent but some very simple systems that work very well. When you have your system first running get a strong light and an assistant to blow some talcum powder around between you and the work piece while you are cutting, you will soon see if it's capturing all it needs to, a spinning blade can make a great difference to the air flow. then check to see if there are chips building up anywhere in the pipes. It's also worth checking with the light around the exhaust to see if it's filtering all the dust properly and checking at the point of cut when the systems getting full.
 
Maximise diameter wherever you can (don’t exceed the inlet diameter of the extractor). Minimise length and changes of direction, use pipe over hose.
That’s about all there is to it.
Aidan

It really is that simple.

I am never keen on the piped in type systems unless you have a big shop, a very big extractor and machines that will not be moved.

I prefer an extractor dedicated to a machine to keep the pipe runs short and also it means that the sawdust and wood shavings are kept separate, just realised I have 6 extractors in my shop 🤣🤣🤣

2 on my table saw (one for the bottom and one for the crown guard)

A HVLP which swaps between my PT and spindle moulder

A smaller HVLP on my bandsaw (I know not ideal but seems to work)

A shop vac dedicated to the mitre saw

A shop vac connected to a boom arm for all my power tools.

Might seem excessive but keeps the dust down (y)
 
Speak to Wood Waste Control in Wooburn Green, or Ducting Express in Leicester, (we have no affiliation to either company, btw), ensure you have all the relevant information to hand and I'm sure they will give you some free, professional, expert, advice.

Failing that, we do have a used Felder RL200 available!
 
Are there any guides, rule of thumb or otherwise, re the max length of extraction hose vs power of chip extractor?

I want to hook 2 machines up to the same extractor but they will be opposite sides of the workshop.

Thanks
The maths is quite involved to do it properly - I can connect you to some sites with formulae if you need it. But that's probably OTT and could be misleading. Air flow down a pipe is reduced by friction of the air flowing over the pipes wall, so the longer the pipe the more the pressure drop and lower the flow resultant flow. Wider pipes have less surface area to volume so the effect is reduced.
One thing that I found useful is a cheap anemometer. https://smile.amazon.co.uk/gp/product/B0876SNWW4/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1, you need to make a pipe that fits the anemometer ie 2.5 inches or 63mm and has adapters to your vac and pipework, but that way you can directly measure the air flow from the vac and down any leg of pipe.

BUT there are so many factors that complicate this that its quite hard for a part timer to get everything right. Sharp bends eg 90 reduce flow significantly, flex pipe is much worse than smooth pipe. So like others have said, try and avoid this solution if you can and either go for a portable vac or have two old house vacs if they will work on your tools.
The KEY first thing is to check your vac will effectively eliminate dust from the tools before doing any pipe runs that add complication. I've found the different tools in my garage need different solutions.
If your tools are relatively small makes of dust with small diameter ports, eg router table, mitre saw then the best solutions as others have said is either have a portable vac such as an old house vac or shop vac and move between the two.
My mitre saw had a really badly designed dust port - good saw a Matabo but a bit old, I've had to drill a port into the blade guard and fit a short skirt to get that to work effetely.
Tools with large ports such as bigger table saws, planers etc need large air flow, so check your system will work before adding more pipes. A large table saw may need a low pressure high volume system, that starts to add expense. I found having two vaccs (old Miele 2000w cylinder and old Dyson) on my cheap table saw worked ok once I modified the saw guard air intake to reduce the waste air flow.
I found having at total 3 vacs in my garage has worked quite well, two one end on the TC and then with blast plate for router and mitre saw and one the the other. I do have some pipes in the ceiling connecting the paired ones together. I did try to use just the one vac and a network of pipes but it did not have enough suck on some tools and was too inflexible for moving things about.
One thing that is quite hard to do, is count dust particles. There are home meters on the market but they are very unreliable, I bought the sensor that is common to the main ones being sold found it was not at all accurate, so best to measure dust using a bright torch or laser pointer and see how effective your piping is.
Finally I would recommend you wear a mask for dust making work such as the TC if you have one as dust is so hazadous. Emptying the bin outside as others have said is a good tip.
 
You don't have to "design" it just get a big enough extractor for the planer, and a vac for the small machine tools. No plumbing needed. But yes you could replace some of your flexi pipe with smooth sided drain pipe, if not inconvenient, not necessarily fixed, but it wouldn't make much difference to short lengths
I empty my cloth extractor bag into a poly bag big enough to go right over the bag - you just up-end them together and pull out the cloth bag. Not much dust escapes at all
 

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