# dual extractor design + cyclone install



## kityuser

I'm trying out a few ideas with my proposed dual extractor system. 







I'm thinking I've made a prize cock up here........ 

turning the yellow motor on results in a pleasing amount of suction and a good exhaust strength. 

However turning the blue motor on results in a reduction of suck from the yellow one by about 80-90% i.e. hardly any suck down the flex pipe. 

Now I think I can explain it, from my distant past physics day I can remember that " an increase in fluid flow results in a reduction of pressure AT THAT POINT", SO at the "y" piece the yellow extractor is effectively sucking vacuum........ 

My question is this: 
if you exagerate this effect, say connect both extractors together end-2-end then both will be trying to suck vacuum (from the other motor). 
If we bring the junction round to 90 degrees, then past to where we are in the picture then we see the effect observed. If we continue round and reduce the angle to 0 degrees using a true "Y" piece i.e. a junction where the 2 air flows join exactly parallel:






would this solve my problem? 

Steve


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## CHJ

No the stronger one will always be starving the weaker. (trying to suck air in reverse through it)
The only way to use the power of both fans is to put them in series not parallel, but you will need to increase the input hose to 150mm+ if you are to avoid starving the fans.


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## WellsWood

I know nothing about fluid dynamics but it would seem fairly likely that in order to maximise airflow, the "common" pipe to which the 2 are connected should be at least equal in cross section to the sum of the 2 individual inlets. 

HVLP extractors only work well when moving the maximum amount of air, what you have done there is to effectively halve the inlet size of the 2 extractors.


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## TheTiddles

You need to throttle the intakes to the pumps proportianally to their output, for instance, if they were identical you would want to make the ducts running to them the same so one wasn't disadvantaged, however, with one more powerfull than the other you will need to increase the resistance to the more powerfull pump so the volume air flow is balanced between the two or one will try and pull air through the other. This sounds like a lot of effort, if they are impellers and not blowers then putting them in series will be the easiest option, it will give you increased pressure and a little increase in flow, though your ducting to the machines could screw this all up.

Aidan


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## wizer

are you really going to notice that much of a difference? Seems like a lot of work to me. Why not just have 2 separate extractors going to 2 separate 'zones'?


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## kityuser

This was the second attempt today. I`ve fired both of them up and the good news is there is a HUGE increase in suck when the second yellow extractor is powered.... a good start.

I connected up my current meter in line and started to test the system.

I measured the following:

blue | yellow
-------------------
on.....|.....off
2.16A |.....x
-------------------
on.....|.....on
2.19A |.....x
-------------------
off......|.....on
x........| 2.90A
-------------------
on......|.....on
x........| 2.94A

Both extractors on give me a current draw of 4.92A with no appreciable difference in tone or volume from each with the other on or off. 

when I stick my 100mm to 63mm reducer on the 4.92A reduces to 4.76A with a slight increase in tone from each. I presume they are being starved slightly. However the suction from the end of a 2 meter length of 63mm drain downpipe is immense :twisted:

I know that reducing the bore is not going to be the most clever of things, but I`ve got an abundance of fittings and piping for wickes 63mm downpiping.....

Steve


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## Chems

That looks really good, I think I may follow your lead at some point as those types of extractors are cheap to pick up now!


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## kityuser

continuing with the general topic of dust extraction, I've been working on my main cyclone yesterday:











has now turned into this mock up, needs bolting spraying and tidying:











I've kept the 63mm inlet and outlets as I plan on using the same size for the rest of the system. The cone was spotted on a walk with the dog at a local woodland walk, found a ranger and asked if I could have it and was to to help myself, the ultimate recycling 

Still to do is an air ramp for inside, the plan is to vent the bottom into a black garden bin that I got from ebay for £2 via some 100mm flexi-pipe.

Steve


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## Fergus

Nice one-look forward to more progress shots . And great use of the traffic cone


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## PeterBassett

Good work! Keep up the progress logs, I'm really interested in seeing how this all works out.


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## Tony Spear

When you say "black garden bin" are you talking plastic? If so, aren't you concerned that it could collapse? There have been comments to this effect on other posts recently.

Edited to correct typo's!


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## Chems

Still looking good, I'd love to know how powerful it is, but I guess there is no way of you measuring it.


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## kityuser

Chems":28ase07y said:


> Still looking good, I'd love to know how powerful it is, but I guess there is no way of you measuring it.



funny you should mention that.
At present I only have the current being drawn by the blowers to gauge any effect I have on teh suction.

I`m thinking of constructing a suction meter, basically a spring scale mounted inside a section of tube with a tighly fitted/gasketted plunger.
The more suck, the more the plunger is drawn in, and the more the spring scale gets deflected/stretched.

In terms of how powerfull the blowers are, turning the second one on with the first already spinning causes a HUGE increase in suck. You can actually hear the effect........ (from the end of the feed pipe).

I`m keen to develop a more accurate metric for assessing the performance so i can debug various scenarios, without the cyclone attached, with it attached with no inlet feed, and finally with 10 foot or so of 63mm attached to the cyclone inlet. 

I`m guessing (and from what I`ve read) that 63mm pipe will starve the blowers somewhat, but like I said I have quite a supply of fittings and pipe already in that diameter.
I`ve tried to make the system "modular" i.e. I can break the top off of the cyclone, incase in future I want to upgrade the bore of the system for say 100mm

as for the garden bin, yes its a plastic black round type (80 litres I think).
if It colapses then I`ll try the strengthen it with some ply ribs, otherwise I`ll got to plan B which is to get a wheely bin.

things are moving a bit slowly this week as I'm on holiday......

hopefully I`ll hit the ground running and have some more pics by the end of the week.

Steve


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## Chems

I'm sure you could buy a cheap air flow type thing, even a wind-meter that you put in front of an inlet, or make a little box that you could put the wind-meter in with an in and an out section and measure the windspeed. 

I guess the brilliant thing about the cyclone is you can use a HVLP type extractor for fine dust?


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## kityuser

hooked the cyclone up tonight:






The chop saw is going to be re-homed and the cyclone situated right into the corner.

Here is the garden bin:





When on the suck is such that removing the garden bin lid is impossible.
Here is the mock up piping to the blowers:





and the blowers will live at the end of my worktop





should make quite a nice addition to a wasted corner.

In operation I'm very impressed. LOTS of holes to plug... lots of air leaks, but hey... it was only a mock up to check the system before I do a belt-and-braces install.

I sucked up about a 1/2 bucket full of mixed dust/shavings/waste. One thing I noticed is some of the waste can stay in the cone for quite a while, you can hear it cycling round accelerating as it decends the cone :wink: 


and of course I haven't installed the air ramp yet.
Next job is to break it all down, install the missing bits and seal everything. Then install in the corner.
I'm thinking at the moment to plumb in to the centre of the workshop (a central down pipe hung from the ceiling) and have a decent size flexi hose which I'll attach to each machine as and when they are in use, rather than pipe to each machine with a blast gate.

quite a bit of talc got through to the bag on the final blower, however I'm not worried because I know the route cause of this CAN be air leaks. Also a little talc is to be expected (as with my vac cyclone).

chuffed at the mo.....

having a beer....
Steve


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## Tony Spear

kityuser":3nsylig7 said:


> (as with my vac cyclone).
> 
> Steve



Did you do a thread on your Vac cyclone?

I'd very much like to make one myself and I'd be grateful for any design info/advice, dimensions etc.

I've done a search but can't find anything.


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## kityuser

this thread 
https://www.ukworkshop.co.uk/forums/view ... c&start=30

morphed into my mini vac cyclone build.

It was a rip off of the dust deputy
http://www.dustdeputy.com/

ok, not pretty but BLOODY hell does it work!

here is that latest piccy I have:






its all rubbed down, sprayed and finished off now.
It was my intention to scrap this mockup and make a glass fibre version (as I have a mate in the trade), but it works so well I don't think I'll bother.

The dimensions are:
10 inches high
7 inches diameter at the top
4 inches diameter at the bottom
40mm waste pipe for inlet and outlet ports
outlet decends 4 inches into cyclone from top.
inlet port enters the side 3.5 inches on centre.

Steve


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## gasmansteve

Steve 
Hows it go with the black garden bin? mine just kept imploding if the inlet tube got a few too many shavings in and thats using a 1250watt vac :? .
When I get the time I`ll knock up a smallish mdf/ply bin just big enough to fit a black bag in.
Cheers
Steve


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## BMac

Hi Steve,

I'm looking at this cyclone business too and I've got a road cone. I was just thinking about your idea to build a box and put a bin liner in it. Would the bin liner get sucked up into the cyclone bit?

Brendan


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## Tony Spear

Steve, very interesting indeed.

A couple more questions:

I notice that most cyclones (icluding your big one) have the inlet and outlet ports fitted in a parallel sided section on top of the cone. Any particular reason why you didn't follow this practice?

Your final dimensions are slightly different from the original proposal (10" high v. 12" and bottom dia 4" v. 3.5") any particular reason for this?
I'm interested in this because in several other places I've come across comments regarding the height v. diameter ratio (1.6 or 1.64) and your original 12" dia. (1.71) seems to be much closer to this than the final 10" dia. (1.43).

What do you mean by "inlet port enters the side 3.5" on centre"?

Has your bucket shown any signs of collapsing under the suction?

Providing that other members of this forum have left any out there :lol: , I think I might try this using a road cone either fitted into a plate like yours, or more likely I'll fit the cone in the top of a ply or mdf cabinet with a removeable bucket inside. I'd have the cabinet door hinged and sealed with draught excluder which would eliminate any leakage problems.

Any comments would be greatly appreciated.

PS; i need to find out about this air ramp business - I can't understand most of the descriptions I've read. Any idea where I can find a photo?

In pumping plants they use cyclones for 2 applications - bloody great big ones (I've seen them nearly 10ft high) for sand separation on the outlets from borehole pumps and tiny little ones to eliminate solids from gland sealing water. I've just looked at a sectional illustration of one of these little ones and the bottom of the outlet pipe seems to be immersed into a central cone within the main cone. Would this effectively be performing the same function as the air ramp?


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## kityuser

gasmansteve":350uzhu6 said:


> Steve
> Hows it go with the black garden bin? mine just kept imploding if the inlet tube got a few too many shavings in and thats using a 1250watt vac :? .
> When I get the time I`ll knock up a smallish mdf/ply bin just big enough to fit a black bag in.
> Cheers
> Steve



Steve, I can completely block the inlet, the cyclone contracts slightly, the garden bin is fine and the blowers start to "race".

no collapsing.

Steve


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## kityuser

Tony Spear":okb3ghse said:


> Steve, very interesting indeed.
> 
> A couple more questions:
> 
> I notice that most cyclones (icluding your big one) have the inlet and outlet ports fitted in a parallel sided section on top of the cone. Any particular reason why you didn't follow this practice?



not sure what to make of this, both my large and vac cyclone have the inlet on the side and the outlet from the top. I have seen designs where both the inlet and exhaust are on the top, but I didn't follow that route.



Tony Spear":okb3ghse said:


> Your final dimensions are slightly different from the original proposal (10" high v. 12" and bottom dia 4" v. 3.5") any particular reason for this?
> I'm interested in this because in several other places I've come across comments regarding the height v. diameter ratio (1.6 or 1.64) and your original 12" dia. (1.71) seems to be much closer to this than the final 10" dia. (1.43).
> 
> What do you mean by "inlet port enters the side 3.5" on centre"?
> 
> Has your bucket shown any signs of collapsing under the suction?
> 
> Providing that other members of this forum have left any out there :lol: , I think I might try this using a road cone either fitted into a plate like yours, or more likely I'll fit the cone in the top of a ply or mdf cabinet with a removeable bucket inside. I'd have the cabinet door hinged and sealed with draught excluder which would eliminate any leakage problems.
> 
> Any comments would be greatly appreciated.
> 
> PS; i need to find out about this air ramp business - I can't understand most of the descriptions I've read. Any idea where I can find a photo?
> 
> In pumping plants they use cyclones for 2 applications - bloody great big ones (I've seen them nearly 10ft high) for sand separation on the outlets from borehole pumps and tiny little ones to eliminate solids from gland sealing water. I've just looked at a sectional illustration of one of these little ones and the bottom of the outlet pipe seems to be immersed into a central cone within the main cone. Would this effectively be performing the same function as the air ramp?



Tony,

I based most of the design on a the dust deputy. Bit cheeky really, I downloaded an image, upscaled and printed it. Then used one known dimension to scale the entire design (I think it was the inlet port diameter). And went from there.

I was limited by the size of the bucket I used but 


> s far as possible I`ve tried to follow the dust deputy design, printing a picture from their website and based on the stated 2 inch inlet port, I derived the measurements:
> approx 12 inches high, top diameter approx 7 inch, bottom diameter approx 3.5 inch


I did have to trim 2 inches off of the height because of the lack of materials I had at the time. I (like you) was skeptical about this mock up as I (like you) had read about the height/diameter ratio. But it seems to have little effect and the mock up works so well I don't really want to change it/replace it.

Dropping the height from 12 inches to 10 and keeping the top/bottom diameters constant would result in an increased "wall" angle. So I increased the lower diameter by 0.5 inches to try to reverse the effect. Could have done the trig to work out exactly the correction, but as a guestimate its probably close enough.


sorry for the gibberish:
"inlet port enters the side 3.5" on centre"?

means 3.5 inches from the top to the centre of the inlet port.... sorry

as for the technicals of why the inlet port enters from the side, and continues into the cyclone rather than stopping flush AND designing and installing and air ramp, see
http://billpentz.com/woodworking/Cyclon ... fm#AirRamp

just a quick note, my vac cyclone has NO air ramp, my largers one is going to get one.

Steve


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## gasmansteve

BMac":17rkelzd said:


> Would the bin liner get sucked up into the cyclone bit?
> 
> Brendan



Brendan
It shouldn`t do providing you get an air tight seal with the wood joints!
Steve


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## Tony Spear

kityuser":tlj0fzvt said:


> Tony Spear":tlj0fzvt said:
> 
> 
> 
> Steve, very interesting indeed.
> 
> A couple more questions:
> 
> I notice that most cyclones (icluding your big one) have the inlet and outlet ports fitted in a parallel sided section on top of the cone. Any particular reason why you didn't follow this practice?
> 
> 
> 
> 
> not sure what to make of this, both my large and vac cyclone have the inlet on the side and the outlet from the top. I have seen designs where both the inlet and exhaust are on the top, but I didn't follow that route.
> 
> Steve
Click to expand...


Sorry, I may have badly expressed my question. What I was trying to establish is why your mini-cyclone doesn't have a straight section on top of the cone, whereas your large one (and most of the others I've seen) does.



kityuser":tlj0fzvt said:


> sorry for the gibberish:
> "inlet port enters the side 3.5" on centre"?
> 
> means 3.5 inches from the top to the centre of the inlet port.... sorry
> 
> Steve



Understood.




kityuser":tlj0fzvt said:


> as for the technicals of why the inlet port enters from the side, and continues into the cyclone rather than stopping flush AND designing and installing and air ramp, see
> http://billpentz.com/woodworking/Cyclon ... fm#AirRamp
> 
> Steve



I've looked at the Bill Pentz site, but after a few minutes my brain begins to hurt :? I'm only a simple mechanical engineer and some of the higher physics goes right over my head, but from my use of cyclone separators in pumping plants I do understand the general priciple (on gland water systems we used to use them in series). 

From something DaveL wrote, I'm under the impression that the air ramp is effectively something like a single turn of a right hand screw thread, which would tend to start the rotation and direct the air flow downwards at the same time. Have I got this correct? If so, I assume that the start of air ramp is installed in line with the top of the inlet pipe.

I understand the need for the inlet to extend into the cyclone (mainly minimises turbulence), but do you still do this if you have an air ramp?


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## kityuser

Tony Spear":16yn4623 said:


> Sorry, I may have badly expressed my question. What I was trying to establish is why your mini-cyclone doesn't have a straight section on top of the cone, whereas your large one (and most of the others I've seen) does.



I see, yup inlet enters the cyclone on the angle rather than into a straight side. Not sure about the physics of this one, just followed the dust deputy design.




Tony Spear":16yn4623 said:


> I've looked at the Bill Pentz site, but after a few minutes my brain begins to hurt :? I'm only a simple mechanical engineer and some of the higher physics goes right over my head, but from my use of cyclone separators in pumping plants I do understand the general priciple (on gland water systems we used to use them in series).
> 
> From something DaveL wrote, I'm under the impression that the air ramp is effectively something like a single turn of a right hand screw thread, which would tend to start the rotation and direct the air flow downwards at the same time. Have I got this correct? If so, I assume that the start of air ramp is installed in line with the top of the inlet pipe.
> 
> I understand the need for the inlet to extend into the cyclone (mainly minimises turbulence), but do you still do this if you have an air ramp?



got it in one, and as for whether you need an air ramp AND extend the inlet into the cyclone, not sure, can't see that extending it inside (as I've done) will do any harm.
I have read, and seen on some american designs that the inlet is sometimes angled down a few degrees, i.e. does not enter the cyclone wall perpendicular to the side. I expect this is the same sort of thing as an air ramp, i.e. to direct the air/dust flow down into the cyclone rather than rotating around the top.

steve


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## DaveL

Tony Spear":21a4bzz3 said:


> From something DaveL wrote, I'm under the impression that the air ramp is effectively something like a single turn of a right hand screw thread, which would tend to start the rotation and direct the air flow downwards at the same time. Have I got this correct? If so, I assume that the start of air ramp is installed in line with the top of the inlet pipe.


Tony,

The air ramp is to help stop turbulence, caused buy the air coming in hitting the air that is already spinning inside the unit. The air does not have to rotate clockwise, if the position for your cyclone in the shop would suit the inlet coming in the other side that is not a problem, let the air rotate anticlockwise it will work just as well.


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## kityuser

DaveL":70epe5n3 said:


> Tony Spear":70epe5n3 said:
> 
> 
> 
> From something DaveL wrote, I'm under the impression that the air ramp is effectively something like a single turn of a right hand screw thread, which would tend to start the rotation and direct the air flow downwards at the same time. Have I got this correct? If so, I assume that the start of air ramp is installed in line with the top of the inlet pipe.
> 
> 
> 
> Tony,
> 
> The air ramp is to help stop turbulence, caused buy the air coming in hitting the air that is already spinning inside the unit. The air does not have to rotate clockwise, if the position for your cyclone in the shop would suit the inlet coming in the other side that is not a problem, let the air rotate anticlockwise it will work just as well.
Click to expand...


doesn't that depend on whether you are in the northern or southern hemisphere? 
:roll: :wink: 

steve


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## DaveL

kityuser":r90i6ot6 said:


> doesn't that depend on whether you are in the northern or southern hemisphere?
> :roll: :wink:
> 
> steve


I bet you have tried the talcum power on the bath water. :-k  [-( :wink:


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## Tony Spear

DaveL":12nh2gk2 said:


> Tony,
> 
> The air ramp is to help stop turbulence, caused buy the air coming in hitting the air that is already spinning inside the unit. The air does not have to rotate clockwise, if the position for your cyclone in the shop would suit the inlet coming in the other side that is not a problem, let the air rotate anticlockwise it will work just as well.



I understand that Dave, I only used right hand thread as an example as both of Steve's have the inlet on the left.


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## SteveJ

Looks a cracking setup, methinks I'm gonna have to have a bash at one of my own  . I can only dream of enough spare cash to invest in a chunky blower though  

One thing which did cross my mind...... could a leaf blower, with the ability to suck, make a reasonable alternative :?: Based on some quick googling you can pick up a 2500W jobbie for around 60 notes, in theory 2500W ~ 3.3HP! ....I can't think of any reason why it shouldn't :lol: .....


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## DaveL

SteveJ":8tuzq0gh said:


> One thing which did cross my mind...... could a leaf blower, with the ability to suck, make a reasonable alternative :?: Based on some quick googling you can pick up a 2500W jobbie for around 60 notes, in theory 2500W ~ 3.3HP! ....I can't think of any reason why it shouldn't :lol: .....


The main difference is the type of motor. Blowers like Steve (kityuser) has are induction motors, quiet in use while most leaf blowers are universal and much louder.


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## kityuser

Sad news for Mrs KU today..... she lost her paper recycling bin side :? 
good news for me, I gained an air ramp! 8) 









Steve


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## Tony Spear

When I realised that I was looking at it from below :roll: , it's exactly as I'd envisaged.

I now can't make up my mind whether to make a mini-cyclone very much like yours or to try and make one incorporating everything I've learned over the last few days! :?

edited to correct typo's!

and add a question: How old is that 4 legged muck magnet you've got there? The only dog that can go out in the middle of a drought and still come home soaked and filthy! :shock:


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## kityuser

Tony Spear":twh3va95 said:


> I now can't make up my mind whether to make a mini-cyclone very much like yours or to try and make one incorporating everything I've learned over the last few days! :?



why not make both, like me :lol:
I suppose really it comes down to horses for courses. The large cyclone driven by the HVLP blowers really doesn't like being restricted in pipe diameter much below the 63mm I'm running it at (and I'm well aware that there is opinion out there that 100mm is the minimum), I know, I`ve tried. So power tools are probably going to be out of the question with the exception of my router table.
Where as the HPLV mini cyclone+shop vac is built for the small tools.....

at present I`m planning on
large cyclone:
1) startrite 351E bandsaw
2) kitty 419 tablesaw
3) thicknesser planner
4) router table
5) extraction hood for drill press

mini cyclone:
1) hand held routers
2) sanding down-draft table
3) general workshop cleaning


The main aim through the whole of this lengthy process is to achieve something on a budget. I was lucky enough to have a load of 63mm pipe and fittings. And I already had a charnwood extractor when another axminster one "came up" locally.
A few performance comprimises, but so far I`m chuffed with how things are panning out on the large cyclone.



Tony Spear":twh3va95 said:


> and add a question: How old is that 4 legged muck magnet you've got there? The only dog that can go out in the middle of a drought and still come home soaked and filthy! :shock:


The 4 legged helper is "fosters" and he is coming up to 4 this year. My bestest mate in the whole world! 

:wink: 

Steve


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## kityuser

spent a little more time last night.






I`ve now applied a lino gasket and a "completely over the top" trick employed by race engine builders. The wire ring is to localise pressure around the cyclone bore hopefully making a better seal.
Common place in race built turbo`ed engines as it makes the head gasket tolerate a little higher pressure aka more boost.

I had the wire hanging around... why not :wink: 

All bolted back together now (sorry no pics the phone ran out), sealed with mastic where needed and ready to connect back up again.

Steve


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## kityuser

*Warning This is starting to get Anal and a bit of an obsession *

OK so I braved the HOT workshop tonight to start fault finding my air leaks on my extractor/cyclone system.

Got this off of the bay for a few quid :






The plug is cut a few mm narrower than the 63mm pipe:






on with the measurements!

first up one blower, no cyclone:





Hopefully you'll just be able to make out 0.25kg

next with both blowers on, no cyclone:




by my reconning just above 0.5kg, thats double the suck 8) 

now by this point its starting to get hot in the workshop and sweat is pouring off (literally).

But I connect the cyclone and start listening for leaks.
Lots of duct tape later (as a temp fix) I end up with:




close, but no biscuit yet :?
Sealing required around:
1) bin lid
2) bin lid -> flexi pipe
3) flexi pipe -> cyclone bottom

and guess what, I now have a partially collapsing bin :twisted: looks like I'll have to "rib" it. 

I gave up under the heat stress 8) 

looking promising, I need to mount the cyclone properly but don't yet have the funds to spray and clean it up.
but I REALLY want to plastic weld all the piping and hook it up :roll: 
I recon I must be still loosing 5-10%...........

Steve


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## kityuser

after securing the funds I`ve finally taken delivery of 
http://cgi.ebay.co.uk/76mm-PU-FLEXIBLE- ... tsupported

which is a dam sight cheaper than:
http://www.axminster.co.uk/product.asp? ... =1&jump=44
200774 Clear Extraction Hose - 75mm x 2.5m £26.65

even if I did try a sneaky and phone the shop directly (as the website stated free delivery) but they weren't having any of it, bit harsh seen as how they would have saved on the ebay and paypal fees.

anyhow, looking forward to getting home tonight to try out my new system 8) 


Steve


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## Rknott2007

kityuser":13ssfwbu said:


> This was the second attempt today. I`ve fired both of them up and the good news is there is a HUGE increase in suck when the second yellow extractor is powered.... a good start.
> 
> I connected up my current meter in line and started to test the system.
> 
> I measured the following:
> 
> blue | yellow
> -------------------
> on.....|.....off
> 2.16A |.....x
> -------------------
> on.....|.....on
> 2.19A |.....x
> -------------------
> off......|.....on
> x........| 2.90A
> -------------------
> on......|.....on
> x........| 2.94A
> 
> Both extractors on give me a current draw of 4.92A with no appreciable difference in tone or volume from each with the other on or off.
> 
> when I stick my 100mm to 63mm reducer on the 4.92A reduces to 4.76A with a slight increase in tone from each. I presume they are being starved slightly. However the suction from the end of a 2 meter length of 63mm drain downpipe is immense :twisted:
> 
> I know that reducing the bore is not going to be the most clever of things, but I`ve got an abundance of fittings and piping for wickes 63mm downpiping.....
> 
> Steve



Could this theory be put into practice with an existing extraction system to boost airflow? How would it work connecting to a axminster wv extractor? one being hvlp the other hplv?
Cheers
Rob


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## kityuser

Rob,

The 2 extractors as pictured are both chip extractors and thus hvlp, I have no idea if you could mix a hvlp and hplv system, I expect not.
Certainly if the hvlp extractor was added to the exhaust of a hplv extractor all that would happen would be that the hvlp would be starved of air........


steve


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## rhoyer

Steve,

Inquiring minds want to know:

Are you still alive or did your inline DCs burn down your house?
Did it all work out or have you scrapped it all and moved on to your next ingenious idea?
Do you have any additional words of wisdom about it 8 years later?

I'm hopeful to hear "yes," "it did," and "not really, just do what I did and you'll have the snake oil."

Best,

Reed


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