Unique Portable CV1800 Enclosure

jsbrow

New member
I pursue woodworker as a hobby in my 2 car garage. In the past year I have upgraded my workshop with the purchase of a hollow chisel mortiser, a 17” bandsaw, and a spindle shaper. My ½ hp powered shop built cyclone dust collector connected to a 4” central duct system was just not up to the job. Therefore I decided to upgrade my dust collection.

My requirements for the new dust collector were:

1) Performance, including the capability to move a lot of air under nominal static pressures associated with a centralized duct system; to effectively separate course from fine dust; and, to capture a high percentage of fine dust.

2) Space, where the unit had to fit under a ceiling height of 101” and occupy a footprint of about 55” wide X 24” – 36” deep

3) Value, i.e. bang for the buck.

I researched a number of manufacturers’ 3 hp dust collectors and eliminated those with short cyclone funnels, believing fine dust separation would be poor. My search was thus narrowed to Grizzly, Oneida, and Clear Vue. I selected Clear Vue’s CV1800 bundled dust collector because it met all of my requirements and was a good value at the sale price offered when I made the purchase. I also bought the MacRabbet Bin Level Sensor.

Before assembling the CV-1800, I developed design requirements that I wanted to incorporate into the assembled unit. These were a unit that neatly tucks into the corner of my garage work shop, occupying a maximum footprint of 55” wide x 33” deep x 101” high; a Dust Collection Bin with maximized volume for collection of wood chips; a Dust Collection Bin that was quick and easy to empty; the ability to quickly determine how full the Dust Collection Bin is at any time; a quiet machine, emitting less noise than the table saw, planer, radial arm saw, shaper, or router table; easy disassembly and reassembly of the Filter Stack for cleaning; and, ready access to all parts of the CV-1800, including the Blower Housing, Cyclone Body, and Filters for inspection, service, and maintenance.

I satisfied my design requirements by building an enclosure of minimal dimensions to house the CV-1800, consisting of a wooden frame with a plywood shell. Unlike most enclosures I have seen in the forum, mine is an integral part of the CV-1800; not a fixed closet type enclosure. The CV-1800 Motor, Blower Housing, Cyclone Body, and Dust Collection Bin all fit inside the enclosure, which measures 29-1/2” wide and 27” deep and is on castors. The top of the Motor sets 2-1/2” down from the ceiling. The Blower Housing Transition extends beyond the side of the enclosure where it meets the Filter Stack. The Filter Stack and Filter Cleanout Box set on a platform that is outside of but attached to the enclosure with a pivot hinge at the front. The Filter Stack Platform can thus rotate out into the workshop. The Platform is secured at the back of the enclosure with a drop-in locking pin. The other end of the Filter Assembly Platform, away from the enclosure, has rounded corners and is supported off the floor by two castors.

The enclosure frame is covered with various sized pieces of ½” plywood. The plywood strengthens the enclosure, can be individually removed for access to various parts of the CV-1800, and hides sound absorbing R13 (3/12”) Ultratouch Denim Insulation. I also used UltraSonic Sound Panels, which are rigid sound absorbing 12” x 12” x 1” panels. A 4’ high x 22” wide x ½” section of plywood with UltraSonic Sound Panels is attached to the enclosure and sets in front of the Filter Stack. The Blower Housing Transition is wrapped with the Ultratouch Denim Insulation. Additionally UltraSonic Sound Panels were installed on top of the Blower Housing and the Motor Mount Plate (leaving a 3” air channel on two sides to vent the motor). The ceiling and corner walls of the workshop where the cyclone sets were also outfitted with the UltraSonic Sound Panels. Although I have no measurements, the sound abatement is effective. The CV-1800 emanates far less sound than my noisiest tools. The wife reports that when operating, the CV-1800 is no louder than our gas fired forced air furnace while she sits in the living room, which is adjacent to the garage. She does not have to adjust the TV’s volume when the CV-1800 is used in conjunction with the band saw.

I used ¾” wide felt weather stripping at the joints between the Blower Housing Transition and the top Filter and between the bottom Filter and the Cleanout Box. I lined the band clamp that holds one Filter on top of the other with the same weather stripping, held in place by pressure from the band clamp. Although the joints are all snug fitting, I doubt that I achieved a 100% air seal; but these are nonetheless pretty good seals. In any event, the Filter Stack can be maintained without have to remove and reapply silicone.

The entire CV-1800 in its enclosure sets neatly in the corner of the garage. By disconnecting the short section of smooth wall flexible hose that connects the CV-1800 to the central duct work and unplugging the three power cords, the entire unit can be rolled out of the corner where I can access all four sides of the unit for service and maintenance. I can access any part of the CV-1800 by removing one or more plywood panels. The filters can be dissembled in a few minutes and cleaned.

The enclosure features a sealed Dust Collection Chamber. The Dust Collection Chamber houses the Fiber Dust Collection Drum, which is outfitted with a handle near the top of the Collection Drum. To empty the Dust Collection Drum, the door to the Dust Collection Chamber is opened and the Dust Collection Drum slides out for emptying – no lid with which to fiddle. A rubber gasket made from a bicycle inner tube is mounted around the upper rim of the Dust Collection Drum, held in place by 1” wide aluminum flat stock on the inside and outside top of the Collection Drum. (I reduced the height of the Fiber Drum and the aluminum flat stock also reinforces the top rim of the drum) The rubber gasket seals the Dust Collection Bin to the top of the Dust Collection Chamber, limiting the amount of chips and dust that could otherwise escape the Dust Collection Drum and accumulate in the Dust Collection Chamber. The Collection Drum capacity is just under 5 cubic feet or about 37 gallons.

In addition to being equipped with the MacRabbet Dust Bin Sensor (wired to shut down the CV-1800 when the Dust Collection Bin overfills), the Dust Collection Chamber has a clear polycarbonate sheet (which seems to attract less dust than other clear materials) mounted on the top of the Dust Collection Chamber and allows viewing the inside of the Dust Collection Drum without having to stop the dust collector or opening the Dust Collection Chamber door. To illuminate the interior of the Dust Collection Drum, two 139 lumen LED Puck Lights are mounted outside and on the top of the Dust Collection Chamber’s top, shining light into the Dust Collection Drum. The lights are controlled by a switch mounted on the front of the enclosure. Also a view into the clear flexible hose that connects to the Cyclone Funnel to the Dust Collection Chamber was built in.

The 240 volt and 120 volt circuits of the CV-1800 pre-wired Control Box (mounted on the side of the enclosure), as well as the Bin Level Sensor Control Box, are connected to dedicated 30 amp and 15 amp circuits respectively with power cords and plugs. The CV-1800 relay and the Bin Level Sensor are plugged into a 15 amp receptacle that has a switch that energizes this receptacle. The switch is mounted next to the receptacle. Another 120 volt 15 amp circuit with a single duplex receptacle is powered by a cord and plug, providing power in the corner of the shop for the shop vacuum and other power tools. This second 15 amp circuit is separate from the one powering theCV-1800 relay and the Bin Level Sensor.

Lastly, I outfitted the CV-1800 with a pitot tube to monitor air flow decline and thus know when to clean the filters. The Pitot tube monitors air velocity in the transition between the Blower Housing and the Filters. It is based on the design detailed at https://www.youtube.com/watch?v=f92mDnLpWFU entitled “SNW45- Woodworking dust collection upgrades- MAKE YOUR OWN MANOMETER filter monitor!”. The only deviation from Stumpy’s design was ensuring that the Pitot tube extends at least 1” into the exhaust air stream.

I estimate that the materials, including electrical supplies, cost around $400. Special thanks to Catherine Currier, Clear Vue Technical Support and Robert Payne, MacRabbet Woodworks for patiently answering my many questions during the assembly of the CV1800.

Now it’s time to install 6” duct work.
 

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Steve P

New member
Welcome to the forum jsbrow. And thanks for the detailed description.

One thing I am not clear on is the covers over the filters. Are the filters exposed? Do you get good sound reduction with exposed filters? Or is the cover removed just for the photo? I picked up a $20-25 mini sound level meter. It is useful for determining the real sound reduction.

Another thing to be careful of is air leaks around your filter bin. Supposedly, the cyclone dust separation gets really bad with small air leaks in the bin. ClearVue cyclones have great separation efficiency, but they depend on a completely air tight collection bin. Let us know how it works out.

Steve
 

jsbrow

New member
Steve,

Thanks for the welcome. Although I have made use of this and many other woodworking forums, I have not posted on any of them. I feel that, where I may have something to contribute, sharing is appropriate.

1. Are the filters exposed and do you get good sound reduction with exposed filters, or is the cover removed just for the photo? The cover in front of the filter stack in the photo only extends down to the bottom of the Top filter and is the only filter shielding panel. Nothing was removed for photographic purposes. I covered this 4' high x 21” wide section of 1/2" plywood that faces the filter stack with 1" thick Ultra Sonic Sound Absorbing panels (1' x 1' x 1"). The Bottom filter is left completely exposed to the workshop Frankly, I left the lower section uncovered because I ran out of 1/2" plywood. But then, after considering whether to purchase more plywood to completely block the entire height of the filter stack, I arrived at a mental impasse. One concern I have in totally blocking the filter stack is the back pressure that could reduce air flow exiting the filters. As built, I have about 3”-4” of clearance from the filters to the plywood panel.

As you suggest and I agree, bringing the filter stack covering panel close to the floor would further reduce the noise emitting from the filters. I am not sure by how much. Rather than pursuing an approach of quantitatively measuring noising reduction, I chose the qualitative approach – how much does my woodworking annoy my wife? With the CV1800 and table saw both operating, the wife does not complain and reports that she does not have to increase the volume of the TV in the adjacent living room. Since she is satisfied, then so am I. By the way, I always wear hearing protection in the workshop. One other observation I made regarding noise, is that a great deal of noise emits from the CV1800 Inlet. I believe that significant additional noise reduction can be achieved by wrapping the inlet with sound abating material. But then, since the wife is satisfied, then so should I. Nonetheless, I may wrap the inlet anyway.

2. I appreciate your caution regarding air leaks in the Dust Collection Chamber (where my Fiber Dust Bin sets). I agree that enough small air leaks not only rob the system of performance, but can also introduce fine dust in the workshop. I am thus far satisfied with the sealed Dust Collection Chamber. When I constructed the Dust Collection Chamber, I caulked all interior joints and penetrations with silicone. The door, where air leaks are most likely to occur, has the ¾” felt weather stripping mounted to the door’s perimeter. The door is secured closed with 3 window sash locks, which pull the door tightly closed. The hinge is a piano hinge. Nonetheless, as I use the system I will heed your advice and remain alert to dust leaks around the door.

Additionally, I will keep an eye of the filter stack for leaks. I doubt that system performance will suffer from air leaks here, but my health may. It seems to me that by the time the air reaches the filters, it is simply trying to escape the system. The CV1800 has already separated course dust from the fine. But in the coming months I will inspect the filter joints for signs of leaks.

3. How well does my build work? The jury is still out. I am still working to complete the 6” duct work and connect it to my machines. I will have to complete this phase of the project and then build a piece of furniture to be able to identify and address any overlooked dust collection problems. I plan a follow-up thread on installing duct work and then, later, one evaluating the performance e of this build.
 

McRabbet

Senior Forum Member
John,

All of the ClearVue community will benefit from this excellent design and very thorough description of your CV-1800 installation. I was happy to answer your questions during your design phase and appreciate your full description of the entire build and in particular of your dedicated and switched electrical hookups for the CV Electrical Box Remote and the Bin Sensor power supply -- these will insure long life and your full control of the cyclone and alarm units (low chance for false alarms or erroneous start-ups). I am impressed with the sealed bin chamber and the polycarbonate top with LED lights to keep track of the bin level. I am curious about how you mounted the sensors for my system and how tight the fiber drum is fitted to the underside of the clear cover. A few pictures might help. And how thick is the polycarbonate? Are you finding dust outside the bin but still in the chamber?

All in all, a very interesting installation!
 
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jsbrow

New member
Additional Bin Sensor and Dust Collection Chamber Info

Additional Bin Sensor and Dust Collection Chamber Info

Robert,

Thanks for the kind words.

1. How did you mount the sensors? Each Bin Level Sensor is installed on its side. I mounted the Bin Level Sensors support bracket to a scrap 2” x 3” so that the short leg of the metal support bracket wraps around the end of the 2” x 3” block. The long leg of the support bracket rests against the face of the 2” x 3” block (front face). Then the 2” x 3” face opposite the face (back face) is mounted to the side of the dust collection enclosure resting on the upper side to the Dust Collection Chamber. The wiring then runs along the back of the Dust Collection Drum (upper side) and exists the enclosure at the Dust Bin Sensor Control Box. The Bin Level Sensors are aligned so that the beam passes through the clear flex hose that is attached to bottom of the cyclone funnel. After I installed the Bin Level Sensors and the two LED lamps, I attached a piece of ½” thick plywood over the top of these electronics. It extends from the back of the enclosure forward to just past the cyclone funnel. This plywood covering prevents the Denim Insulation from settling into the Bin Level Sensor beam. When I empty the Fiber Drum, the Bin Level Sensors are not disturbed since these are mounted outside the Dust Collection Chamber.


2. How tight does the fiber drum fit to the underside of the clear cover? The top of fiber drum itself sets about ¾” below the underside of the Dust Collection Chamber top. Initially, I left the ¾” space open. However, when I tested the design, I found dust accumulating outside the Fiber Drum inside the Dust Collection Chamber. Therefore, I installed a bicycle inner tube (to act as a gasket) at the top of the Fiber Drum to close off the ¾” gap. The bicycle inner tube extends upward from the rim of the Fiber Drum about 1” – 1-1/4”. The Fiber Drum now seals effectively (though probably not perfectly) against to the top of the Dust Collection Chamber. In my limited testing, very little to no dust now escapes into the Dust Collection Chamber and the Fiber Drum still slides in and out with little effort.

3. How thick is the polycarbonate? I purchased the polycarbonate sheet at Lowes. I do not recall exactly, but the sheet was about 8” x 10”. I measured the thickness to be 1/8”. I cut the sheet into four sections; a) Dust Collection Chamber Window, b) two LED Lamp Covers, and c) Cyclone Funnel Window.

4. Are you finding dust outside the bin but still in the chamber? Once I installed the bicycle inner gasket on the upper rim of the Fiber Drum, very little dust escapes the Fiber Drum. However, to be fair, I am just finishing up the Duct Work System. The real test will come when I put the CV1800 to work on my next furniture project.

5. Photos? I attached photos attempting to show the interior of the CV1800 enclosure at the top of the Dust Collection Chamber (where the LED Lamps and Bin Level Sensors are located), the interior Top of the Dust Collection Chamber, the Fiber Drum, and the Electrical Setup.
 

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McRabbet

Senior Forum Member
John,

Thanks for the clarification and additional photos. And again, you've done a great job. Of course, the true test will come when your duct work is complete and you generate some real dust. We'll all look for your next thread when that happens.
 

jsbrow

New member
Performance Review

Performance Review

Since I have now used the CV 1800 in a woodworking project, generating a Dust Collection Bin full of debris, I thought I would follow up with a performance review of the new dust collection set up. A better review would be after generating a dozen or so Dust Collection Bins full of debris, but, at the rate I complete projects, that could take quite a while.

Building the CV 1800 enclosure, installing SDR-35 6” duct work, and a Blast Gate Sensor System took about 3 calendar months working 4 days a week, with life interrupting my efforts. I described the installation of the duct work and the Blast Gate Sensor System on this Forum in the Category “Piping and Dust Pickup”, in threads entitled “Duct Work Installation Using SDR-35 6” Pipe” and “Blast Gate Sensor System – Shop Made; Low Voltage.”

I completed the design for a China Hutch consisting of a Base Cabinet and Upper Display Cabinet. In the last few days, after much prompting from the wife, I began the build of the Base Cabinet by milling Walnut stock at the jointer, the planer, table saw and radial arm saw. These machines all have dust pickups for CV 1800 dust collection. In so doing, the 40 gallon fiber Dust Collection Bin had to be emptied for the first time. Its contents consisted of saw dust and jointer and planer shavings.

Overall, the system works great. I am very well pleased, although the sting from writing all those big checks remains. But then, as time passes and projects are completed, that sting will fade rather quickly.

Pick Up at the Machines. Dust collection in my shop is not perfect. I still have debris around the planer, jointer, table saw and radial arm saw. On the other hand, there is very little debris and a huge improvement over the old ½ hp dust collector outfitted with a shop built cyclone. The uncaptured debris, in my opinion, is a function of the dust collection pickup capturing dust at the machines. I rigged my own radial saw dust hood, which keeps the front of the work table clean, but some dust escapes the dust collector behind the fence. A couple of tablespoons of shavings escape the old Craftsman 6” jointer and deposit on the floor on the infeed end of the table; likewise with the Woodmaster 12" planer. The cabinet table saw, which is collecting dust only within the cabinet (which I sealed as best I could) spews the most debris – on the table top. This is due to the absence of an overhead collection port.

Still, dust collection is WAY better!

Noise Level. The CV 1800 noise level is managed only to the extent that the wife, watching TV in the living room only complains when the woodworking machines themselves are running. The CV 1800 in its enclosure can barely be heard inside the living room (it shares a wall with the garage workshop). This was the result I sought.

Static Charge. No static electrical shocks have occurred when opening or closing the blast gates, even with the CV 1800 running. No dust seems to be drawn to the outside of the piping. The grounded foil tape installed both inside and outside of the piping seems to be doing its job.

Dust Collection Bin. While planing, the LED lamps illuminating the Dust Collection Bin were handy. After running all of my stock through the planer and before readjusting the planer, I checked the bin (with the CV 1800 running). This kept me from being interrupted during a planer run. The McRabbet Bin Level Sensor could have shut off the CV 1800 in the middle of a run – not catastrophic, but an inconvenience.

McRabbet asked for a follow up on the performance of the Dust Collection Chamber and the Dust Collection Barrel. I have to confess that when I opened the Duct Collection Chamber, I was astounded. I was sure I would be cleaning up stray wood chips that escaped the Dust Collection Bin into the Dust Collection Chamber. There was none. It was clean as a whistle. The bicycle inner tube gasket mounted to the top of the Dust Collection Fiber Drum worked great.

The Dust Collection Drum slid out and back into place in less than a minute. After emptying the debris on the compost pile and sliding the Dust Collection Drum back into the Dust Collection Chamber and closing the Dust Collection Chamber door, I was back to planing. It was extremely easy and quick.

Leaks. I found no dust leaking from any of my duct work joints – so far. I have other branches that I have not yet used. Sealing the duct work joints with 4” aluminum foil tape and then fastening the joints with sheet metal screws seems works well.

Steve P cautioned me concerning dust leaks in and around the Fine Dust Collection Bin under the filter stack, if I understood him correctly. Heeding his caution, I inspected the joints where the Filter Transition meets the Top Filter, where the two Filters meet, and where the Bottom Filter meets the Fine Dust Collection Bin. 1” wide felt weather stripping was used to seal the joints rather than silicone. This was done to make disassembling and cleaning the filters easier.

I found no sign of air leaking at the Filter to Filter joint nor at the joint where the Bottom Filter meets the Fine Dust Collection Bin. However, there was very little dust observed in the Fine Dust Collection Bin, suggesting that most dust entering the filters is being lodged on the filters. As the filters clog, the pressure within the filter stack will increase and leaks at these joints could occur.

The joint where the Filter Transition meets the Filter Stack is another story. Some fine dust was seen on top of the Filter Stack. This appeared to be a mix of fibers from the denim sound abating insulation and perhaps fine wood dust. I really cannot say. Before completing this transition joint and in addition to the felt weather stripping that sets atop the metal filter flange and makes contact with the lower surface of the Filter Transition, this joint was wrapped with 1” felt weather stripping, secured in place by 3 wooden L brackets. The weather stripping encircling the Filter Transition and Filter Stack joint was peeled back. Fine wood dust was observed on the felt weather stripping. This obviously indicates a leak at the joint, but it is controlled by the encircling felt weather stripping. Since there was no obvious dust on material near this joint including a 3 mil trash bag holding denim insulation in place and very close to this joint, I am satisfied, at least for now. Perhaps later I will redo this joint and maybe use silicone if this leak becomes worse.

I believe the reason for this leak is the difficulty I had shimming the filter stack to eliminate any gaps at this joint. There is maybe a 1/16” (or less) gap between the Filter Transition and the Filter Stack on one side, where the escaping dust was observed. Where this joint was tight on the other side, no dust was observed.

System Performance Monitor. The Pitot tube installed to monitor air flow decline and thus show when it is time to clean the filters is providing air velocity information at the Filter Transition. This device consists of clear tubing in the shape of a U, filled with water, and mounted to a board marked in ¼” increments. The water level with the CV 1800 OFF is 5”. At this time, the CV 1800 produces an air velocity in the Filter Transition that raises the water level to a height of 7-1/2” to 7-3/4” on one leg of the U. When this value drops to about 7”, I will clean the filters.

Blast Gate Sensor System. I described a low voltage blast gate sensor system in another thread. The system consists of a light corresponding to each blast gate (in my case 9 lights). The light is ON only when the corresponding blast gate is open. I found this very convenient when milling stock, where, after planing to thickness, I began to mill project parts, moving from the jointer to the table saw to the radial arm saw. At a glance an open blast gate at an unused machine was easily identified. This was handy when the milling operation was interrupted while inspecting lumber and looking for the next project part. The switches that mount to the blast gates and about which I was initially concerned, seem to be holding up well.

Conclusion. I am very happy with my upgraded dust collection system. It performs well and makes a huge difference in keeping the shop and my lungs clean. And most importantly, the wife is happy because I am tracking less dust into the house and building her China Hutch. Happy wife, happy life!
 

jsbrow

New member
One Thing I Would Do Differently

One Thing I Would Do Differently

I have used the CV1800 enclosure described above for a couple months and have discovered a minor problem with the viewing window into the Dust Collection Chamber. Anyone considering a Dust Collection Chamber with a viewing window into the Dust Collection Bin may find this post helpful.

As I have used the CV1800, especially when collecting fine dust from the drum sander and down draft sanding table, dust collects in the corners of the viewing window. The center portion of the viewing window remains clear, providing an unobstructed view into the Dust Collection Bin. It appears that turbulence exists in the corners of the viewing window.

When I construction the Dust Collection Chamber, a rectangular hole was cut in the ½” plywood top of the Dust Collection Chamber. The polycarbonate sheet was secured and sealed on the outside top of the Dust Collection Chamber, leaving a ½” deep recess around the viewing window inside the Dust Collection Chamber. As dust leaves the cyclone, it swirls along the top inside surface of the Dust Collection Chamber before dropping into the Dust Collection Bin. Turbulence at the corners of the recess allows dust to collect in the corners of the polycarbonate sheet. The center of the polycarbonate sheet is scrubbed by the swirling air and remains clear.

A better way of installing the polycarbonate viewing window would have been to route a shallow rabbet around the perimeter of the rectangular hole on the inside surface of the Dust Collection Chamber top. The polycarbonate sheet would then set in the recess flush with the inside top of the Dust Collection Chamber. I believe that had I installed the viewing window flush to the inside surface of the Dust Collection Chamber, the scrubbing action of the swirling air would have kept the entire viewing window clean and turbulence eliminated.
 

Rushton

New member
John, I don't know if you still monitor this thread, but if you do I have a question concerning dust collection for your Radial Arm Saw. What have you found to be effective in setting up collection at the RAS?
 

jsbrow

New member
Rushton,

I have a Craftsman radial arm saw. I only use it to cross cut at ninety degrees. I cut bevels on the table saw. Mitres are usually cut at the RAS using a jig whose angle matches that of the mitre. This allows the RAS to remain set for ninety degree cuts. My feeling is that it would take a great deal of time to re-set the RAS to cut a perfect ninety degree angle after setting it to cut a bevel or mitre.

The ancillary advantage of keeping the RAS at ninety degrees is that it simplifies dust collection. If you keep your saw set at ninety degrees the alternative design below may be worth considering.

I became aware of this alternative design for RAS dust collection after completing my setup. If the RAS is kept at ninety degrees, it may be worth considering. Here are the YouTube links to this alternative and apparently more effective design…

https://www.youtube.com/watch?v=YRFjRvQTckM

Follow up video describing the underside design…
https://www.youtube.com/watch?v=Z9TyYI800cw

The design of my RAS dust collection hood is difficult to describe. My description is probably confusing so if you are interested in pursuing this design and have further questions, I will try to provide answers. Also the photos hopefully will offer some clarity to my description.

The goal of the design is to focus and direct air flow along the path of the blade. In order to direct the air flow, I made an effort to ensure that air would flow into the dust collector from the front of the saw (where the operator stands) to the back of the saw (where the column is located) more or less along the path of the blade. Therefore air flow from above, behind, and from each side of the blade had to be restricted. Since I could not see that the dust hookup on the blade guard would collect much dust I blocked off this dust port.

Even having achieved reasonable success in directing airflow along the path of the blade, the CV1800 leaves debris on the table. It seems to require several cuts before debris become noticeable and after a dozen or so cuts, I typically vacuum the table with the shop vac. Nonetheless, this dust collection setup does collect a lot of debris.

I suspect the problem is that the RAS fence blocks air flow along the surface of the table. I prefer a zero clearance fence, but wonder whether a wider slot where the blade passes through the fence would result in more effective dust collection.

The dust collection shroud for my radial arm saw consists of a pair of boxes which set behind the radial arm saw carriage and on the blade side of the radial arm. One box is a tower to which the dust 6” collection pipe connects. Pieces of snap lock pipe were fitted into the corners of the tower box. The pieces of left-open 4” HVAC pipe eliminate dead spots that would otherwise exist if the corners were left square and makes the interior of the tower box more or less round. The HVAC was cut lengthwise to get the just right fit.

A second box connects to the tower box and sets behind the RAS blade. Air is drawn into the tower box through this second box. This second box runs from the tower box to the RAS column and has an opening to receive debris. This opening is a slot that is about 28 square inches to match the cross section area of the 6” dust collection pipe. Directing debris into the interior of this second box is achieved by a section of 4” HVAC snap lock pipe cut lengthwise that acts as a ramp to direct debris smoothly into this second box from the RAS table. One edge of the HVAC pipe is bent to lie flat of the RAS table.

A fixed panel is attached to the top of the tower box. This panel ensures air is only drawn in from the RAS blade; not from above. In order to further direct air flow from the RAS blade, a hinged panel is attached to the tower box and opens until it contacts that back side (column side) of the RAS fence. This swinging panel fits snug to the table and the top fixed panel. This panel is hinged so that it can be moved out of the way when a stop is clamped to the fence. Both of these panels (the fixed and hinged panels) are on the blade side of the RAS arm.

A large piece of plywood is mounted behind the boxes described above to further direct air in a way to capture debris. Air cannot enter the dust collector from behind the RAS due to the rear mounted plywood. A third hinged panel is attached to this back piece of plywood. This third panel is located on the side of the arm that is opposite the blade. It further directs air by preventing air from entering from the right side of the blade. This panel can be swung out of the way for cleaning or adjusting the RAS arm to the right.
 

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Rushton

New member
Hi John,

Thanks for your nicely detailed reply and photos! I use a DeWalt 790 and it's my primary saw for milling up my lumber and for some fine work as well: cross cut, angle cuts, ripping. As you suggest, I try to keep the arm at 90 degrees for as many cuts as possible, but compound miter cuts and rip cuts present a real challenge for dust collection solutions. I'm hoping to gain more effective dust collection once I get my new CV1800 installed this winter. I look forward to taking more time to review your comments and what's worked for you as I make my plans.

Thanks for the link to Bob Hatcher's saw kerf solution. I've also been considering Tommy Tompkins' variation on this low height design with holes drilled through the fence:
https://www.youtube.com/watch?time_continue=2&v=uHv3jghJe9U (starting at 0:36)

And also applied by Frank Howarth:
https://www.youtube.com/watch?v=Rwd6i3UmbMI (starting at 11:48)

What I like about your box, and the box solution shown in this demo by Matt Morgano, is the potential for some more flexibility in rotating the yoke of the saw for other than 90 degree vertical cuts.
https://www.youtube.com/watch?v=b5VKdd43T6A

Again, many thanks!
 

Wirednuke

New member
Hey John,

Sorry for thread Resurrection half a decade later. I'm planning on building a similar enclosure and I was wondering what you did for motor cooling? I saw you added "channels", what does this entail exactly, and is the enclosure open in any way to allow airflow?

Thanks,

Phil
 

craigcclick

New member
Hi Phil- I myself have just re-visited these 'noise' threads to look for a solution. I just recently re-installed my CV1800 system in a new shop. Before, I had it totally enclosed, including the filters. But because my filter clean-out was not sufficiently sealed and I was not sufficiently venting the air back into my shop, I had problems with dust inside the enclosure.

So now, I'm starting over again. I started by enclosing the motor and blower only, venting with twenty 1" holes around the sides, and using foam. It didn't help with the noise, and the motor overheated. But perhaps that is because my blower will run for an hour or more at times.

I'm going to move my filter stack further away, enclose it, and wrap the ducting with acoustical material. I'm also going to enclose the cyclone and impeller, leaving the top of the motor exposed, as I think the impeller is the largest producer of noise. For the moment I will not enclose the dust bin as I have a good seal on my receptacle. I'm also going to wrap my 8' inlet 8" duct with acoustical material.

I'll post when I'm finished.
Craig
 

craigcclick

New member
I wonder if I'm about to make a mistake. With the idea in mind that separating the filter stack from the cyclone and wrapping the plenum, I thought I would do just that. Unfortunately, to separate the two is not possible in a straight line. I have to make a 90° bend 2' away from the outlet, before continuing another 4' to the filter. My afterthought: will this bend increase back pressure and reduce efficiency? Thoughts, comments? IMG_4195.jpg
 

craigcclick

New member
If anything, by adding the plenum it's noisier. The efficiency seems to be the same. I downloaded the free NIOSH sound meter; before the plenum it said 86db, now it's 93. I think there's an error somewhere as I don't think it's that much noisier.

I'm going to now enclose the cyclone and filters in two separate enclosures, using mineral wool, as well as wrap the plenum in mineral wool. IMG_4221.jpg
 

jsbrow

New member
Phil,

Sorry of the late reply. I am normally notified by email of activity on this thread. However, I did not receive an email when you posted.

The enclosure completely encases the cyclone funnel, dust collection barrel, and the impeller housing. The impeller motor and the filter transition pierce the enclosure. Acoustical batt insulation surrounds the cyclone funnel and the impeller housing. Rigid foam was installed in the dust collection chamber (where the dust collection barrel sets). The only gap in the enclosure is where the dust collection chamber view port was installed.

I exercised caution when insulating the top of the impeller around the motor. I applied acoustical insulation everywhere I could while staying about 3” away from the motor. Insulation completely encircles the motor but is 3” away from the motor. However the insulation encircling the motor is NOT continuous. There are two 3” wide gaps (the channels you mentioned) in the insulation. The two gaps in insulation are on opposites sides of the motor and aligned with motor intake ports. These gaps are intended to allow air to easily and freely enter the intake ports situated on the lower part of the motor. When insulating around the motor, I found the Sonic acoustical panels worked very well because they were rigid (1’ square x 1” thick). When fixed in place the panels stay put.

In summary, when building and insulating the enclosure I ensured that air could freely circular around the motor; air could be easily drawn into the lower part of the motor, and that the air pulled into the motor could freely exit the top of the motor (the top of the motor is about 3” from the ceiling of the shop).

I have built a number of projects in the In the 4+ years since installing the CV1800. The CV1800 collects dust from all my machines. When milling lumber the CV1800 may run continuously for 2 or more hours. I also refrain from frequent starts and stops of the CV1800, instead leaving it run between operations. Thus far I have had no problems with the dust collector.


Craigcclick,

I suspect the long plenum with two 90 degree elbows will rob the CV1800 of some performance. Whether there will be a perceptible drop in performance, I cannot say. Insulating the plenum and around the filters would, it seems to me, reduce the noise level some. When insulating around the filter stack, leaving a space between the insulation and the filters would be needed to allow air to escape the filters. But then I doubt I am suggesting anything you have not already thought about.

You did not mention insulating the impeller housing. I have to believe that most of the noise emits from the impeller housing and the travels mostly with the airflow, ultimately to the filter stack.
 

craigcclick

New member
The two photos show the cyclone and filter stack enclosed with mineral wool 5cm thick attached to the interior walls. The plenum is also wrapped in 5cm thick mineral wool. What a difference; the sound meter reads 72db. The top is not enclosed, allowing the motor to keep cool. It's not uncommon that the system will run 2-3 hours a stretch, and dump 4-6 barrels a day. IMG_4268.jpg IMG_4269.jpg
 
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