Thread: My Clear vue installation

Chris, this means that if I drill a 102mm hole in the front lower door of my little bandy, the dc will work better. I am thinking the the top left corner, when the dc hole is bottom right corner, as you stand in front of the machine. Entirely doable.

Or take the lazy approach as I did and crack the door open with the nearest bit of timber I could find so there is a gap for air to enter. Jet carry the sealing of the cabinet to ridiculous lengths by actually putting a rubber seal all round. When i questioned them about it they did not seem to grasp the concept at all. I know I will have to modify my new saw when I get it just for this reason.

Originally Posted by Chris Parks

. . . . . . some users have taken the approach of blocking all air flow into the cabinet thinking that the leaks are the reason they have poor DE from the cabinet when they should in fact be creating more leaks!

Originally Posted by Timless Timber

I have a question if I may?.

The impeller used in the down under clear view cyclones.... is it 15 or 16 inch in diameter?

I have a reason for asking.

We are using the VFD (Vertical Finger Decapitator, er sorry i meant Variable Frequency Drive) to spin up the impeller from 50htz to 60hts to match the US Power supply specs, to get it to spin 20% faster for greater throughput of air = yes?

Its just that in recent days I'd exchanged emails with Bill Pentz about this (in relation to my question about direction of spin and the Coriolis effect) and in his response he happened to mention something about this subject.

Words to the effect,

"To fit the cyclone within the typical 8’ ceiling and be able to get a full 1000+ CFM through a 6” diameter duct, I engineered the air channels, blower, etc. pretty carefully. The result is even with quite a bit of resistance you still end up getting the full 1000 CFM we need for good fine dust collection with the standard 15” diameter Clear Vue Impeller when turning at 3450 RPM, meaning typical 60 Hz cycle current. For 50 Hz current I strongly recommend use of the 16” diameter impeller to compensate for the slower motor speed." (My Emphasis)

So this makes me question if maybe we are running 15 inch impellers, with a VFD to spin them up to 3450 rpm's (60htz) when instead it would be cheaper - easier to just spin a larger diameter 16 inch impeller at 50htz & eliminate the VFD?. (I think BobL might have explained this was done so the unit could run off a standard 15 amp socket & not require a special 20 amp circuit and socket)?

or

Are we spinning a 16 inch impeller now up to 60-htz with the VFD and maybe exceeding the min 1000 CFM air flow Bill designed these clearviews to run at?

You can see I am still getting my head around all this.

Sorry if it is a thread derail.

I9 think that Chris and BobL have answered these questions for me and thanks for that.

As both say there are more benefits to the VFD than just the availability of higher speed. These include the fact that without 3 phase power you cannot run a clearvue CV1800 or CVMAX without a VFD to convert the single into 3 phase power. All Clearvue systems in Australia are supplied with a 3 phase motor as this is the only practical way to get the torque needed to power the impeller.

The CVMAX comes with a 16" impeller to provide the additional power to mallow more than one machine to be used simultaneously. Even that machine used where there is a 3 phase supply will benefit from a VFD. It allows you to maximise the output of the machine when you need to.

As BobL says it allows decreased as well as increased speeds when this is a better option. It also provides a soft start which lowers the power demand on start-up and potentially prolongs motor and bearing life.

The downside of the bigger impeller is that you need the larger main duct run which does add to the total cost of a dust collection system.

For those using only one machine at a time the CV1800 with a VFD is perfectly fine. The 15" impeller places less demand on the main ducting run so the smaller main duct and smaller cost is adequate.

I think we will see an increase in the use of VFDs for many more motored products as people realise the benefits and potential power saving even for things such as pool motors. It would be hard to justify changing an existing motor and adding a VFD but an initial installation would quickly justify the additional cost of the VFD.

Originally Posted by rusel

OK anyone got some suggestion or link re a bandsaw and dust collection. I have made a new table insert with bigger and more hole than the original one. Link here for those who wish to see https://www.woodworkforums.com/f27/mo...1/#post1687782
Russell

You might be able to do better than I with your cyclone setup Russell, but I don't yet have a big dusty and have been surviving with just a Festool CT33 shop vac. Despite this I have an approach that gives me extremely good dust collection under the table. Just using the shop vac I get virtually zero dust in the bottom cabinet.
The way I did this was by shaping a bit of 55mm PVC to fit under the bandsaw table, hard up against the blade insert, and squeezed in just above the bottom blade guides. This pipe has a slot cut in it 3/4 of the way through for the blade to ride in, and the pipe is open at the other end to allow airflow. So while there is not a high volume of air, there is high pressure air being pulled across the blade as it passes through the pipe and it sucks the saw dust out of the blade gullets before it enter the cabinet. I couldn't be happier with how well this works, so if your saw has space in the right places, this is a great approach.
I have attached a couple of pictures so you can see what I mean. This one is very rough- after shaping the PVC with a heat gun and slotting it in the correct location, I used car bog to mold around the PVC and the webbing on the bottom of my table. I also embedded 2 rare earth magnets in the car bog so that the whole thing will easily fasten to the underside of the table and locate itself properly (due to the webbing). You might notice a small screw in the picture - this screws up into my blade plate just for a bit of added peace of mind so that the pipe can't shift.
The car bog was very messy and difficult to work with - if I did it again I would probably try some of that air dry craft clay instead, or at least take the table off the saw and tip it upside down to do the molding of the bog. Another small improvement might be to make the whole collection apparatus part of the table insert so that it is sealed to the underside of it, removing any gap for dust to escape and causing a bit of suction down through the blade hole as well.
I'm not sure if the cyclones give enough pressure for something like this to work, but might be worth considering a combination approach where you use a high pressure shop vac for that initial collection point under the table.

Originally Posted by shedman

. . . . The downside of the bigger impeller is that you need the larger main duct run which does add to the total cost of a dust collection system.

You only need the larger ducting if you plan to use more than one 6" duct connection at a time. Not using larger than 6" ducting effectively wastes most of the capacity of the bigger impeller.

Larger Trunk ducting does not need to be round in cross section - it could be suitably sized rectangular cross section MDF which adds work but in terms of cost probably works out to be about the same price as 6" PVC.

I think we will see an increase in the use of VFDs for many more motored products as people realise the benefits and potential power saving even for things such as pool motors. It would be hard to justify changing an existing motor and adding a VFD but an initial installation would quickly justify the additional cost of the VFD.

Given used small 3 phase motors can generally be picked up for <$50 and the increased availability of cheap VFDs it is becoming easier to justify changing existing motors and adding a VFD. In the last two years I have acquired or purchase 10 three phase motors ranging from 1/6 to 5 HP for an average price of $32. So far I have converted 3 machines in my shed to running from VFDs (+1 is in the pipeline) and I reckon they are well worth it.

Oddy.... I think you get this weeks gold star....And your thought of combining it with the table insert is just better again...but I agree with you this would only be good for vacuum setups.
I have just put up a post on my bandsaw thread Mods to my hammer n4400 about doing somthing simular idea but using a DE

I agree with bobl on VFD... I have 3 of them now and a 4th coming and also thinking about changing the pedestal drill to one,,, save mucking around with belts as often.

Pick up some flex hose this week 160 and 120 mm 3mt of each from Felder, pricy but good stuff, cheap if I use it for the next 20 years. Think I will just have to prove that

Started with the bandsaw and you can see that on my theard https://www.woodworkforums.com/f27/mo...-n4400-175331/

Have been run the cnc this week and just having no wood dust floating around was just worth all the effort of putting in the DE.
The product of the cnc needs to be sanded, so the downdraft table will get another testing soon.

Doing this work has giving me the chance to run different equipment with the DE running and the noise leave of the DE is the quietest piece of gear running.


I have one question that you folk might be able to answer, I get dust or other light weight bits like a leaf that got sucked up and when there get to the cyclone do not spiral around and drop into the bin but just keep rotating around the cyclone funnel horizontally, Understand most of the dust end up in the bin just some does this dance. Why?

Originally Posted by rusel

I have one question that you folk might be able to answer, I get dust or other light weight bits like a leaf that got sucked up and when there get to the cyclone do not spiral around and drop into the bin but just keep rotating around the cyclone funnel horizontally, Understand most of the dust end up in the bin just some does this dance. Why?

The continued rotating is due to factors like the air speed inside the cyclone, the mass of the leaf and also it might be acting like a sail and catching wind, the same thing is going on with a circus act that is called "the wall of death" (or something like that) a car or bike has to maintain a certain speed for it to be able to ride around the wall otherwise if it slows it falls off the wall and crashes down. If you slowed the speed down the leaf should fall.
There was a forumite a while back who posted some video of cyclone design and what happened with different particle size, air speed, etc....
Ill see if I can find....




Pete.

Gunnaduit's thread, post 61 has a pic of different particle sizes and how they behave inside a cyclone
https://www.woodworkforums.com/f200/e...54/index5.html

pete thanks your link has one answer, See below, I get the same as figure C and some D
When you shut down the power the partials slowly drop down while still rotating till there drop into the bin.

6.1. EFFECT OF PARTICLE SIZE DISTRIBUTION ON CYCLONE WALL EROSION

To investigate the effect of particle size distribution, a wider inlet particle size distribution (1 μm to 160 μm) was simulated using the Lagrangian tracking. The resulting particle trajectories are shown inFigure 13. It is clearly evident that the larger particles are collected at the walls while the smaller particles escape downwards in spiral manner. This is because the drag force on the smaller particles is larger than the centrifugal force preventing their transportation to the cyclone wall. The results show that the particle with sizes < 40 µm escape from the bottom of the cyclone after a certain residence time while the particle with sizes > 60 µm keep spinning around the mid level for significantly longer.Wang et al. (2006) have shown this phenomenon experimentally using ceramic balls. One possible explanation lies in the balance of the centrifugal force versus the gravitational force. As the larger particles roll down the conical part, the centrifugal force on the particle increases because the radius of the cyclone decreases while the tangential velocity of the particle remain almost the same. The larger particles will eventually be collected at the solid outlet due to the particle-particle interaction. However, some of the particles will stay at the cyclone wall. There also appears to be a critical value of the particle diameter below which the particle is not expected to be collected at the outlet. The critical value of particle diameter is related to the cyclone geometry, gas inlet velocity and particle properties.
FIGURE 13.

Single particle trajectories of size (a) 5 µm b) 20 µm (c) 40 µm (d) >60 µm.

Gunnaduit did quite a bit of digging to find info on cyclone design, that thread has some useful links, I did think there was a video somewhere there showing exactly as shown there in the pic.




Pete

Hi Russel
Thanks for starting this thread, very useful read for someone installing a Clearview.

I am interested in your dust bin construction. I am installing a CV1800 and have overcome most of my problems mainly concerning my 8ft ceiling. Finding a suitable squat low weight bin is however proving difficult (see my post regarding Fibre barrels). Chris has suggested building one from plywood like yours. My concerns are how to make it airtight and how to transport/empty it, without getting dust all over me.

Could you post how you sealed yours, how it is constructed and how you empty yours
Thanks
Ron

If you wanted to make it cylindrical out of ply there is a form of ply called "bendable plywood" that can be formed/rolled into a surprisingly tight radius without any pressure.
If you were to glue two 7Ply plywood (or MDF) circles on for top and bottom it would easily be strong enough without any frame.
That way you can make it as squat as you want to.

Hi ronboult
The box is a simple construction 6mm ply on a 20 x 35 mm pine frame. I used liquid nails and staples to construct it and then sealed all the joints with liquid nails and let harden before use.
The top edge seals onto a foam tape seal under the lid. I made a method of lifting the lid and holding it while the box can be slide out from under.
I think the box I made might be to big for one to lift is the only mistake, I might have made but will find out when it fills up. This would depend on if it is large savings or finer sandings.
When I get back to the shed I can take more detail photo if you want more info.


I have made some 120mm gates one for the BS top and the other maybe for the pedestal drill.
I have got good at making short length of 120 pipe out of 160mm pvc pipe, Use this to attach the flex to gates ,BS and junction into main trunk line.
Will post some pic when back.

R