extracting mdf dust

[JPEC]

Julian check if the impellor on the Charnwood is metal - most these days are plastic - a no no by Bill's standards.
I paid £150 delivered ( or was it £165) for a 3HP dual extractor on Ebay.
Keep looking
Barry

Thanks Barry

Yes the spec said 'indestructable steel impellor'. Was yours new and how good is the suck? i am planning to use it for a ducted system with a cyclone in the not too distant..
Where did you get your mini cyclone and do you think my henry will be up to the task?

ps the cyclone looks great look forward to seeing it complete

 

[Barry Burgess]

Was yours new and how good is the suck? i am planning to use it for a ducted system with a cyclone in the not too distant..
Where did you get your mini cyclone and do you think my henry will be up to the task?

ps the cyclone looks great look forward to seeing it complete

A mini cyclone will help your henry as about 95/98% of the chips and dust remain in the capture drum of the cyclone so the vacuum does not get blocked and works better. I use mine on power tools and at the bottom of the router table attached to the router.
I have run +/- 15 meters of soil pipe in my garage with blast gates at all the ends. With the 3HP extractors with filters not bags you have to be careful as is sucks everything in site. Do not use T junctions but rather use Y junctions. Mine will cope with 3 blast gates open(just) but works well with 2 open

 

[Inspector]

I've read through all 11 pages of this post :shock: and several of the contributors have said that they are reluctant to make a cyclone out of sheet metal.

The solution is obvious to me but seems to be escaping the masses. You're woodworkers........make them from wood! It's what I plan to do once I get past a few other projects first.

If you substitute a couple thin layers of plywood for the sheet metal. Cutting, forming and joining the different components should easily be within the abilities of almost everyone.

The other option is to use stave construction with solid wood (that's I want to use). You don't need to do much designing as that's been done by Bill Pentz already, just adapt for the wood, (make sure the insides are the same size as he recommends and add the wood thickness to that). The inner pipe can be made of wood, plastic, or a metal stove pipe. One benefit (assumed) is that it should be a bit quieter than a metal one. Even a cyclone made of 3/4" / 20mm pine is going to last many, many years before it could possibly wear out. The blower doesn't need to be on top of the cyclone, it could be bolted to the ceiling of the shop and a short hose connecting the two.

Since there are always woodworkers that like to make masterpieces of any tool they make, I wonder how long it will take to start seeing them sporting marquetry, exotics, and carvings?

Hope the idea stimulates the discussion a bit.

 

[nickson71]

I think I may have heard about a wooden cyclone somewhare on the net but it was just a reference like " other people have also used this material and that....etc" ............ I guess you could also minimise wear at key locations in a cyclone like the point where the dust stream first hits the inside of the cyclone by using a more resistance liner in this area.

I guess the problem would of using wood would be the time taken to build one of these things ........ I'm still relatively new to woodworking whilst I sure I could make a wooden version I know that it would take a long time to finish .......... the version Barry is making look interesting as it could be made in a weekend (hopefully).

I guess I want to get a good extractor quick so I'm not damaging my lungs for any longer ........

 

[prawnking]

IMHO a wooden cyclone wouldnt be as good as sheet steel due to the friction on the surface, i belive that steel has a heck of a lot lower surface friction to that of wood and that i belive is one of the fundimental principals of the cyclone is the fact that dust is pushed a gainst the edges of the cyclone and then slips down the cone, if this where wood i would think that dust wood stick, BUT i might be wrong

cheers
shaun
btw i am just about to go and get my camvac

 

[Inspector]

nickson71

While it may take a bit longer to make a wood cyclone with Bill Pentz's plans it would perform more efficiently than than one put together quickly. And I am not saying that to put down Barry's design but if the goal is to protect ones breathing system then it doesn't make any sense (at least to my way of thinking) to take shortcuts.

Time and money are getting harder to get all the time for most working people but it always surprises me when I see a hobby woodworker buying the latest cordless tools that cost 2 or 3 day's pay each (and they have many) yet they want the cheapest safety gear. Look at the number of routers we have (I've got 4) and the dozens of bits that accompany them and you realize that that represents 3 weeks of wages after taxes, and we can justify them and still want more. That dust collector system that will allow us to live longer to enjoy that activity is the one that gets a lower priority, probably because it actually doesn't actually make anything. It's like being at work an hearing the GM say that " We might as well close the shop if we have to follow all these regulations." The choice is up to the individual, and my apiologies if this took on the feel of a rant.

I've got a 4 bagger collector and got rid of the 30 micron bags and replaced them with 1 micron bags. Made a big difference so I can hold off on the cyclone for the time being. After the cyclone Is made the 1 micron bags will be retired and replaced with a cartridge house with 7 (unless I can get more from work) .5 micron filters that will give me almost 1800 square feet (approx 175 square meters I think) of filtration area. That should let the dust collector and me, breath a lot easier.

Good luck with your system.

 

[nickson71]

I guess you could coat the inside of a wooden cyclone to lower the friction .... maybe some sort of paint ........ but I don't know how long that would last ........


maybe the fact that all the dust rushing through would "sand" the surface smooth ...... I guess someone would have to build one out of wood and let us know ....... It could be an interesting experiment

 

[nickson71]

Hi Inspector


I can see where you are coming from and I don't think it's a rant ........ If you can take short cuts and still get the result your after I don't mind ........ that's why I'm interested in how Barrys design works out.

I'm about to spend the money to get my extraction sorted and as my current system is very poor I want to get it right ....... I need to spend the money on the blower (may have to buy a new chip collector just for the blower) the cyclone, the filters and the ducting whilst making blast gates etc ....... So if there are short cut in terms of time and money that does not effect the performance I'll be interested

But then again the more I think about the wooden cyclone the easier it is to make and it would be interesting to see if it worked and how long it could last. ......... If I didn't have a project list as long as my arm I may consider it just as project.

 

[Barry Burgess]

Inspector I am already using 2 .5 micron filters each of 20m2 on my extractor. I am using Bill Pentz's spread sheet for the dimensions on my cheap cyclone and am making a air ramp as well. What I am trying to do is use easily available parts so that just about anybody can make one. Bill also suggests using the 14" diameter if you are using smaller motors - mine is 3HP which is large for most home shops in the UK. I reduced the inlet as most people use 4" pipe. I am using 7" rather than 8" in the original design for a 14" diameter ( all converted to mm)

Barry

 

[Jake]

I reduced the inlet as most people use 4" pipe.

You're not using 4" pipe though are you Barry?

 

[prawnking]

woo hoooo
just got my lean green sucking machine

its awsome!!!!

1 motor on gives about the same suction as a powerfull house vacuum

switch on the second motor and holy poo the suction is awsome, bearing in mind i have never had any dust extraction units to compare to but IMHO its a good buy.
noise huh i dont know what some where complaining about with both motors tunning its no louder than my house vacuum
aparrently you can also duct the exhaust to outside which reduces the db

now for the cyclone :wink: :wink:

cheers

shaun

 

[Barry Burgess]

As part of my research to cheap cyclones I went to CCL who are into ventilation and air movement products across the country and asked for a bespoke conical reducer from 450mm to 150mm with a length of 738mm and to add a piece of 450mm body of 542mm. This is exactly to Bill's spec. I got a price of just under £140 without delivery. This is the body of the cyclone without the inlet or outlet and the most difficult to construct for woodworkers. This is a good price considering I got prices of £645 to £1175 to do the complete job( that down south prices). The other option is the Ikea £22 flower pot and the 65 litre drum and work on your part.
I am likely to buy the CCL option to see the difference with my cheap and cheerful

 

[JPEC]

I am likely to buy the CCL option to see the difference with my cheap and cheerful

Hi Barry,

Is the 'cheap and cheerful' up and running yet, let us know how it works.

Julian
Still looking for a cheap extractor on ebay :x

 

[Barry Burgess]

Julian I have had no time but hope to find some tomorrow
This is where |I am at

Just did a mock up - its bigger than I expected. I will need to get more 6" flexible hose to reach the top from the extractor.
If I built a 18" diameter one I would have to use a smaller collection bin and side mount the impellor and motor as it would be at rafter height
I completed the 150mm X80mm to 100mm diameter pipe for the inlet and I just have to fit it to the drum.
Barry

 

[RogerS]

Do you ever get any time to do woodworking, Barry :wink:

 

[Mike.C]

Bill Pentz's recommends using 6 inch ducting on his cyclone. So with this in mind, how many of you will be using this size, and how many will be sticking to 4 inch?

If you do use 6 inch, would you lose much suction/power when you reduce the 6 inch ducting to the 4 inch outlet, which most machines use?

Cheers

Mike

 

[Adam]

Bill Pentz's recommends using 6 inch ducting on his cyclone. So with this in mind, how many of you will be using this size, and how many will be sticking to 4 inch?

If you do use 6 inch, would you lose much suction/power when you reduce the 6 inch ducting to the 4 inch outlet, which most machines use?

Cheers

Mike

I use 4 inch pipe, but the workshop is so small the runs were small. If you terminate a 6inch pipe at the very end with 4inch, it does not significantly reduce the airflow provided the 4inch pipe (flange) or whatever the machine has is very short.

Adam

 

[Barry Burgess]

Do you ever get any time to do woodworking, Barry :wink:

Yes that's what is using up most of my time. - the cyclone is just for fun. At present I have no neighbor on the side where my workshop is so I can usually get in a couple of hours each morning early. My list just gets longer
Barry

 

[engineer one]

barry

if building cyclones is for fun you must have some serious issues :lol: :lol: :lol: :lol:

paul :wink:

 

[Jake]

Unfortunately that isn't the case with a HVLP extractor, as I keep trying to say in this thread, HP extractors are much more tolerant.

To quote Mr Pentz on dust hoods:

Does a 4" connection at the machine negate the benefit of the 6" duct going right to that machine? Yes, it kills the dust collection performance. At typical airspeeds and pressures for dust collection, air is virtually incompressible. Air can speedup some to get around a short obstruction, but just like a water valve, closing down the opening greatly restricts flow. The standard 4" connections on our larger hobbyist machines kill the CFM below what we need to collect the fine dust. We pretty much have to replace all the 4" ports on our larger machines if we are going to collect the fine dust at the source.

To quote him on 4" ducting:

For instance a 1.5 hp dust collector that can move a maximum of 1100 CFM moves far less air than that maximum depending upon what sized ducting we use. This typical small shop dust collector blower only generates 4" to 6" of pressure when working. With the added overhead of our filter and minimum ducting, that pressure is only ample to move about 800 CFM when hooked up with a short piece of 6” flex hose. That pressure will only pull about 550 CFM when connected with 5” flex hose and only about 450 CFM when hooked up with 4" flex hose.

Whether you have a modest 1/2 HP 600 CFM blower to a roaring 5 HP maximum 2300 CFM blower you need to balance the ducting size. We constantly trade off our ducting size to move the right air volume at ample speed with minimum resistance. To get the needed 800 CFM that larger tools need for good fine dust collection through a 4" duct or hose you need about 9,000 FPM that takes a monster impeller and huge motor. That's why knowledgeable woodworkers use 6" ducts and 6" flex right to their larger machines even with portable dust collectors. Without a monster blower, if your duct is smaller than 6" to your larger machines, then it will not move enough air to capture the fine, most unhealthy dust. The best you can hope to do is make your system a little more efficient.

You can't pick and choose here, if you are going the low pressure route you have to make sure that air resistances are minimised all the way through. As Pentz says, 4" ducts or 4" hoods mean that you cannot comply with his requirements with any normal sized HVLP extractor.

That's why I think that in practice, the Camvac HP route is likely to be up there or there-abouts performance wise with any normal system you can devise. It doesn't suffer as badly from the limitations of hobby equipment and hobby-sized workshops. The "it only does 333cfm" argument stumbles as not many people are going to invest the time effort and space to get their systems working to anything like the free-air specifications of the HVLP systems that look so much better on paper.

That said, I love Barry's system and wish I had the space and time to invest in one myself!