Noise control

[dwdrury]

Freq. Analysis

Freq. Analysis

jgveill,

My plan is to do just that, and also try some of the noise reduction items we've been discussing in this topic. I have an old Win95 Pentium II box I can use, along with one of those awful microphones that came with computers of that era. I have no idea how good, or bad, the microphone is, but schemed to generate a tone sweep, put it on a CD, and play it through some decent speakers. That should give me a fair idea, with the GSpec spectrum software PWH Chris suggested. Assuming the mic is decent, then I should be able to get the wav and/or MP3 file.

Assuming Ed agrees its OK, I'd have no problem posting it, but am aware competitors may use it against him, so I will defer to his wishes. We can cross that bridge when we get to it. My CV 1800 is still in boxes, so I cannot supply an audio file today. I must complete some other projects prior to starting its assembly, so I don't foresee being able to supply the information until sometime in September, at the earliest.

As FORTRAN is the only foreign language I once spoke, all I can say is your English is bound to be much better than any attempt I might make in your native tongue, so no need for apologies.

Ultimately, Ed and others are quite correct, that the most effective noise reduction is going to be putting the unit in an insulated closet. Please note the installation in Ed's new shop, in the photo gallery section. If you haven't gone through that yet, there are a lot of good ideas, for noise control, assembly tips, and novel solutions to various challenges that inevitably crop up in custom projects. Thus I recommend you spend some time and go through the photos and comments there, if you haven't already.

Regards,

DWD

 

[woodman]

I just uploaded photos of my completed enclosure to the gallery. Hope they help.

 

[dwdrury]

Completed Enclosure

Completed Enclosure

Steve,

Nice looking box & door!

Just one question: a few messages ago you noted some noise levels, specifically the 83 dB with the beast enclosed. Are the photos of that configuration, a mockup (i.e., perhaps not as neat and tidy with a hinged door, but essentially the same sort of baffle), or is this something "extra"? And if the latter, any improvement in the noise numbers?

I find I'm at least a month behind, and have not started my CV 1800 installation yet. Only about halfway through that other project I foolishly promised. Getting old, I suppose.

Regards,

DWD

 

[woodman]

DWD, Thanks.

I took a new reading this morning to be sure. With one 6" gate open to the TS, it reads 80dB. As a reference, the TS reads 84dB. Both readings were standing in front on the TS.

As for the difference in readings from my previous post, it -could- have something to do with the foam insulation I used to seal the through holes for the muffler and cone. I used the yellow Great Stuff expanding foam when it read 83dB. I've since cut it all out. It got so rigid, that I assumed it was transmitting vibrations to the enclosure. Before I sprayed the foam in there, the whole cyclone unit was able to swing just a bit when bumped.

I'm going to consider using the DAP brand latex expanding foam instead, since it stays soft once cured. I'll let you know if there is any difference. You might notice, that that is what I used around the cyclone inlet through the enclosure. It's white in color.

I don't know if this would have contributed to the decrease or not, but I'll share it anyway. I installed a notty pine T&G floor in the shop over the dirty, hard plywood. If nothing else, it sure looks good.

BTW, I ran the cyclone for about an 90 minutes over the weekend, which is the longest run time I've had so far. The motor was VERY hot to the touch. I wonder how long I would have gotten without the thermal overload switching. I've have to look into venting the enclosure into the attic, and hope it doesn't make it loader outside. The other day my neighbor mentioned that he can't hear the cyclone -inside- his house anymore. Yikes.

 

[dwdrury]

Pine floor, small space

Pine floor, small space

Steve,

Now that you mention it, does look like a rather small space. I suppose I reckoned you'd vented it someplace, somehow.

It might be worth making or leaving some sort of air hole towards the bottom of your enclosure, maybe around the muffler? If you then open up a hole above the motor into your attic, you'll provide a nice flow path for cooling air, a chimney effect. Though the hole(s) might result in some noise increase.

Also wonder if doing so might increase the noise noticed by your neighbors. Always good to keep the neighbors happy. But I think a minor increase in noise would be justified by a reduction in potential for premature motor failure or, extreme case, fire.

Also must admit I didn't notice the nice pine flooring until you mentioned it. What, had to keep up with the guy who put down that nice cherry floor? Just teasing. And jealous.

Regards,

DWD

 

[woodman]

Good point about the chimney effect for ventilation. I'll do that.

Funny you mention that...Yes I was inspired by the cherry floor. It does look a lot nicer then the dingy plywood. At about $1 sq.ft, I couldn't resist.

Only downside is it dents easy, but that'll just add character. Plus, after 4 coats of poly, it's real slick. I may have to add some grit to a top coat to make it safer. Never thought of that potential before I started.

 

[Matt]

Motor Hot to the touch

Motor Hot to the touch

Woodman,

I won't say that it won't kick out but it does get very hot To hot for the touch...I have run my dust collector continuous for 12-14 hrs with at least 1-6 inch gate open all day and only kicked thermal overload out once and i replaced it because i thought it was bad. Turns out it is very hard to push because of where it is located. In looking at your installation it looks as if the top half is completely isolated from the return air going back to your shop so that there is no way for the heat to exchange with the return air. Opening a hole in the ceiling is going to exposed the whole thing to attic tempertures which won't be good either but may help. Adding a fan and hole in the top half will expose your shop to noise again so I really don't have any better suggestions. Unless you have a problem with overheating I wouldn't worry too much about it and also be aware that start/stop cycles will tend to overheat the motor faster than running continously with gates closed(amp draw goes down when everything is closed). Seems like there would still be alot of noise coming from the filters even though they are located at the bottom. Our Max installation is running at 65 db at 10' http://gallery.clearvuecyclones.com/A-new-home-for-Clearvue/New_Building_f_005 is a pic of the room and http://gallery.clearvuecyclones.com/A-new-home-for-Clearvue/New_Building_f_012 shows the inside lined with window screen and insulation. I know it's too late for you but maybe it'll help others.

The motor is designed to run at a Max of 104 ambient air temp. That does not mean max temp that you will feel on the outside of the motor which will most likely be much much higher. Also it will run continuous at that temp at full load of 20.8 amps. It has an insulation class f which means the insulation on the windings inside are rated at 311 degrees F. This does not mean the outside of the motor. One last note is that the thermal overload will protect the motor if the temp is to high so don't worry too much that it is hot to the touch. Here's a pdf link to basic training about motors from leeson electric for more information about thier motors..... http://www.leeson.com/cgi-bin/fetchpdf.cgi?/literature/tech_info/pdf/basictraining.pdf


Matt

 

[dwdrury]

Chimney effect, follow on

Chimney effect, follow on

Steve,

Obviously Matt is the expert. However, I'd like to draw your attention to a couple of things.

Personally, with our hobby, I'm petrified of fire hazards, all that wood, the opportunities for spontaneous combustion and the like. So the heat being kicked off by the motor would, in the enclosed space you've given it, make me as nervous as a long tailed cat in a room full of rocking chairs. So I'd be looking for a way to enhance its cooling potential, even if, as Matt observes, it probably won't bother the motor.

Have no idea where you're located, I'm in the southern SC swamps near Hilton Head and Savannah, GA. Yes, it gets toasty in our attic during summer, but with the vents and fans, our attic temps don't often exceed 120 F. So provided you have adequate and perhaps powered ventilation in your attic, I think venting excess heat into that space would be the easiest to accomplish.

I also reviewed your earliest photos, to reaquaint myself with your installation. On the other side of the back wall of your alcove is, if I've read your descriptions properly, a space for storing your gardening supplies and equipment. So there's an optional area for either obtaining cooling air or dumping the excess heat. Or both, maybe a loop with a circulation fan like a 4" or so computer fan. Depends, I suppose, on how sensitive that area is to noise and heat, if its reasonably well vented itself, etc. But by sourcing cooling air from there, you might be able to avoid opening up the hole around your muffler and thereby providing a path for noise back into your shop.

But as you've got the cyclone now less noisy than the table saw, I think a dB or so added back by removing the foam blocks from around the muffler wouldn't be onerous. Try it and see.

It would be a neater and easier installation to remove the foam blocks, open a hole above the motor into the attic, and rely on the chimney effect. A fan for motive flow is just another potential failure. But, as Matt points out, the wisdom of doing that depends on your attic.

Regards,

DWD

 

[Matt]

No expert

No expert

I was simply going by motor specs and 120 in the attic will overheat the motor. I hope you don't run into a problem but you have some ideas if you do.

Matt

 

[dwdrury]

Yet another mea culpa

Yet another mea culpa

Sorry, Matt, if my earlier post came out wrong. I only meant you have more experience and expertise with these motors than I. No offense intended.

True, 120 F is over the operating environment for the motors. But in a reasonably well ventilated attic, that really is only seen in the upper portions. Lower, an attic should be only, oh, 10 to 20 F above ambient. And if Steve provides for ground floor air from his shop or storage area, the motor's local ambient, prior to turning it on, should be even lower, maybe half way between source and upper attic temperature.

I see Steve's tag says he's in Pennsylvania, which would suggest his attic maximums will be much less than you or I see here in the south. Granted, were he in Tucson, a path to his attic might not be the best idea.

Regards,

DWD

 

[Matt]

heat energy from motor

heat energy from motor

No offense taken. I agree with what you said and at this point there needs to be some air flow from somewhere. I am thinking that the motor at 18 amps of power draw and 82% efficient comes out to be about 700 -800 watts of heat being generated(correct me if i am wrong).....sounds like alot but that motor is doing alot of work! That much heat in that samll an area isn't an ideal situation and the chimney effect that you guys had already come up with sounds great.

Matt

 

[dwdrury]

Sound Recording

Sound Recording

Just to follow up on a portion of this thread that was under discussion last August. In Message 40, jgveill requested a recording of a CV in operation. Jameel Abraham beat me to it, and documented his efforts nicely in the "Building a noise-blocking closet" thread in this noise control portion of the forums. He also made a noise recording, and has a link available for the MP3.

Regards,

DWD

 

[jgveill]

Freq analysis

Freq analysis

Hi everybody,

I just saw DWdrury post and downloaded the mp3 recording. I'm quite busy right now but I should be able to post some real pictures and analysis this weekend. I briefly looked at that and I could not see any real frequencies pattern ... it " looks " and sounds like noise with higher levels in the low frequency range, as we could expect. It's fun to have 4 different recordings that we can compare.

I will be back soon !

Jean-Guy

 

[R and D Nikkel]

For what it may (or may not) be worth, since we have no sound monitoring equipement...
Ed, in his general overview to noise, says "At 80 db, you can't listen to the radio, talk on the phone or carry on a conversation without shouting. It's not a comfortable level...IMO."

Our unit therefore is putting out less than 80 db. With it running and no gates open, you can easily hold a conversation. With a 6" port open, you can still hold a conversation, but need to concentrate a bit more. Once you turn a machine on - you have the machine noise too. What I find really different is how much the system amplifies the noise the jointer/planer puts out. Take our fitting away from the machine, leaving both running, and it is half the volume of the two together. This doesn't happen with anything else where the pipes are permanently connected. I'm not sure why that is, but it definitely is - with the machine in either orientation.

It is not that loud outside either when we are venting outside.

(We have now put our up our stuff in the gallery under Rod and Denise's shop if anyone wants to see.)

 

[wade]

Motor heat

Motor heat

Woodman,
One idea would be to add a small line inside the enclosure to pull air from the enclosure. The line could be setup to pull air directly through the motor. If the enclosure is perfectly sealed, then adding a 1-1.25” hose to allow air in would probably not have any significant effect on noise.
Wade

 

[Matt]

Planer

Planer

Hi,

My planer is also louder with the 6" line open than when it is closed and i am just guessing that it it caused by the spinning blades smashing into that much air.

Matt

 

[jgveill]

Noise Frequency analysis

Noise Frequency analysis

Hi everybody,

I took Jameel's noise file and look at frequency analysis. The frequency analysis is showing average frequency for 5 to 8 seconds when cyclone or saw was operating at full speed.

All graphs show levels rapidly dropping after 16 000 HZ. MP3 encoding creates this. No having these frequencies is not a problem as most people cannot hear them, dogs can !


Graph shows sound #, using the same order we hear them.



First : no clear harmonics. We see bumps in every graph but no clear repetition pattern. Sometimes we can hear frequency beating, that's probably coming from these bumps that are not always there when I take shorter sanples. The level of the bumps compared to the average level is also not meaningfull. No specific frequency to kill. Just noise ... We can see that lower frequency's level are always higher than higher frequency's levels.



No surprise, sound # 3 ( door and blast gate open ) is the loudest. Frequencies up to 2000 HZ have the highest levels.



Sound # 4 ( Unisaw ) has the highest levels for high frequencies, but we do not feel this as really loud because low frequency levels are low compared to other sounds.



Sound # 1 and # 3 are really similar at high frequencies. At lower frequencies, Sound # 1 is about 6 db quieter, which really makes the difference.


As expected, sound with quieter low frequencies are the nicest ones to hear.

Jean

 

[dwdrury]

Possible Conclusions?

Possible Conclusions?

Thanks Jean-Guy, that graph illustrates Jameel's data much better than I could do with GSpec (Operator error on my part, most likely).

From this data, though, I think perhaps we're in a position to draw some conclusions. As what seems to have become the norm, I might as well fly some up the flagpole and see who salutes.

First, the evidence seems to indicate my earlier speculations about blade passage (especially around the gore point) aren't confirmed. Thus my plan to rework that transition probably won't yield much.

Second, products like Dynamat that work in the low to mid frequency range are most likely to have a positive effect (though others such as Nako and Steve (Woodman) report mixed results with those sorts of products, if memory serves).

Third, the relatively flat noise output across this spectrum hints to me there's a lot of eddys and shearing going on in the blower housing. Stepping back a bit, yeah, that's what one might expect from a non-airfoil impeller. The design was selected for its durability and self cleaning features, not to minimize noise by creating as smooth an airstream as possible.

The other interesting tidbit Ed provided some time ago, some sort of cone arrangement to help turn the air entering the blower from vertical (up the tube) to horizontal (out the housing exit). The idea, if I have it correctly, was to keep air from hitting the blower's back plate and perhaps setting up resonances. However, shortly thereafter, I seem to remember Matt said they tried coating the backplate with various materials, to no perceptable advantage.

I'll probably still try my envisioned experiments. It appears I'm a good two months behind (usual!). I have three things to try: Modify the blower housing's gore point to a radius instead of the sharp break of the "stock" units; make a little blower outlet extension, to go between the outlet and transition pieces, and line it with Basotech (those Mr. Clean Magic Erasers); and one or more Styrofoam cones at the blower inlet. Thought I'd try them individually and then in combination, see if there's anything to be gained. Though something tells me at least the gore point experiment will prove ineffectual.

Regards, and thanks for all the great work,

DWD

 

[r j cedar]

noise control and dust pickup objectives

noise control and dust pickup objectives

[FONT=&quot]I am about to buy a cyclone. But Im looking for a quiet solution as the workshop is in the house basement. Most dont have this situation and/or don't care about noise. [/FONT]

[FONT=&quot]Isnt it tricky how even if you shift objectives only a little, the solution changes. This is a discussion about objectives and levels of dust collection effort. Would like comments plese.[/FONT]

[FONT=&quot]My objectives: a quiet shop. fine dust pickup. Are these mutually exclusive?[/FONT]

[FONT=&quot]Translation: [/FONT]

[FONT=&quot]QUIET:dont want to add any more noise to machine running noise. And when machine is not running, would like NOT to hear the DC (much) as it runs on in the background. So I will put the DC in a cyclone room with sound block, muffled return duct etc.[/FONT]

[FONT=&quot]FINE DUST: hmmm, books say 350-500 cfm objective for the tablesaw, and I was only considering one dust pickup on the Tablesaw, not 2. So IF I do not change this objective, my cyclone choice may change. Newer objectives say arund 800cfm for the tablesaw with 2 pickups. [/FONT]

[FONT=&quot]Was looking at the 1.5 Oneida Component Cyclone and 2hp Oneida Super Dust Gorilla. Now looking at Clearvue CV 1800 RH Combo- 1045 +85.00 S&H[/FONT]

[FONT=&quot]For my ductwork static pressure, return duct SP, dirty filter SP factor: I get these CFM at my most distant tool, the tablesaw:[/FONT]
[FONT=&quot]1.5 Oneida Component Cyclone - 350 cfm. bare minimum using old books as a guide.[/FONT]
[FONT=&quot]2.0 hp Oneida Super Dust Gorilla - 600 cfm. 14.25"x4" fan on 2hp.[/FONT]
[FONT=&quot]CV 1800 RH Combo- 1045 +85.00 S&H - not sure. Need the fan curve but with a 5hp motor on a 15" fan, it must be LOTS. Could not find the fan curve for this machine at[/FONT]
[FONT=&quot]http://www.clearvuecyclones.com/Order_Page.htm[/FONT]
[FONT=&quot]I really should apply the proper fan curve to my SP situation. Havent yet, will ask some questions anyway.[/FONT]

[FONT=&quot]One the forum, many complain about the air nose / duct noise / noise at the blast gate. It has been observed that blast gate and duct noise can easily be greater that the cyclone noise. Thats not great. How to quiet that too? I guess there is a direct conflict in my objectives: quiet shop and fine dust pickup?[/FONT]

[FONT=&quot]Have not seen much on how to quiet blast gates/ductwork. The noise is is a direct consequence of very high cfm/velocities. BUT I suppose if one keeps duct diameters large (6" or 5") to the tool, then this must be all one can do to keep the NOISE AT A MINIMUM. Right? And the consequent lower static pressure is good for high cfm too.[/FONT]

[FONT=&quot]But can I go to a Clearvue 5hp high velocity/cfm solution and still have my quiet shop?[/FONT]
[FONT=&quot]I need that fan curve to calculate how high is high velocity. [/FONT]

[FONT=&quot]The clearvue approach seems to be 2 pickups per machine. Then the new, higher airflow requirements for a e.g. tablesaw - 800cfm - gets split into 2 - 400 cfm minimum objectives to maximize max fine dust pickup. And given the 5hp motor and high cfm/velocities some higher actual cfm is actually delivered throught these 2 pickups. Maybe having 2 (maximum sized) pickups "quiets" the overall system too, as much as is possible. Quieter than having smaller e.g. 4" sized pickups I mean. This is confirmed by ed[/FONT]
[FONT=&quot]http://www.clearvuecyclones.com/Bullentin/showthread.php?t=754[/FONT]

[FONT=&quot]saying[/FONT]
[FONT=&quot]Inside the shop.no gates open........................ .........72 db[/FONT]
[FONT=&quot]4" port open(sound of sucking air)..............................85 db[/FONT]
[FONT=&quot]6" port open(sound of sucking air)..............................80 db[/FONT]

[FONT=&quot]But I would guess these levels are relative to how much cfm is going through. Not sure what the specific cfm situation is for these 2 decible ratings.[/FONT]

[FONT=&quot]Up to now I have only been thinking of 1 pickup per tool except for the miter saw. A common thought I suppose when planning dust collection for the first time.[/FONT]

[FONT=&quot]Looking at 2 levels of objectives: A quiet shop plus....[/FONT]

[FONT=&quot]DC Level 1 objective: 1 pickup per tool/high dust capture. Recognize some fly dust from the table saw blade will escape, and the in room ceiling air clearner has to take some of that out, and you breathe a little. A lot less dust than no DC and room air cleaner. Quiet shop (?) Here I have either a 350 cfm or 600cmf 'solution' in one 5" base pickup, based on dc choice, with differing noise and fine dust pickup differences. [/FONT]

[FONT=&quot]DC Level 2 objective: 2 pickups per tool/max source dust capture. retool machines to accept 2 5" ports, above and below. The current clearvue approach? [/FONT]

[FONT=&quot]Would the clearview approach ( 2- 5" ports running ??? cfm each - situation specific), be quieter than having one 5" base pickup port running 600 cfm? Got to work out the numbers. But Hmmm, maybe it is. Somewhere I heard decible emmissions from noise sources are not cumulative. Here you have 2 pickups, the table saw, and the dust collector going, plus the noise in the pipe. But Im not sure if 80 db plus 80 plus x, y and z db really adds to 80 db. Likely something more?[/FONT]

[FONT=&quot]So what should I do?[/FONT]
[FONT=&quot]Stay at level 1 and get the 2hp Oneida and an in-room air filter? [/FONT]
[FONT=&quot]Go to level 2, but calculate the cfm being put thorugh those 2 pickups to meet the minimum objective of 400 plus 400 = 800 cfm. If its pulling ....1200cfm???....maybe the noise problem will not go away.[/FONT]

[FONT=&quot]What is your experience?[/FONT]

[FONT=&quot]Thanks![/FONT]
[FONT=&quot]RJ[/FONT]

 

[dwdrury]

Some Thoughts

Some Thoughts

RJ,

Some random thoughts as perhaps a partial reply to your post.

First, lets get this bit out of the way. Ed & Matt provide a fan curve, see http://www.clearvuecyclones.com/Specifications.htm and scroll down a bit.

If you wade through Bill Pentz' site, he makes a very good case for the need for 800 CFM, and 6" ducting. Should you choose to split the 6" at a tool, say 5" at the main dust pickup and 2 to 2.5" at the blade guard, you'll end up with the same effective area, which, in turn, will yield the same velocity through the ducting. Too much is a waste, too little and you can get chips falling out of the airstream and collecting in the ducts.

The thing I liked about ClearVue's system is it is designed to yield this sort of performance, and to move that amount of air at those speeds, you need at least 3HP, according to Pentz. Though the curves suggest upwards of 1500 CFM, bear in mind that's with minimal, if any, ducting. For anybody's system. By the time you get down to the tool, you're in the 800 ballpark with the CV.

Obviously you've spent some time here, and are concerned about the noise. My installation starts in a week or so, thus I cannot provide you firsthand perceptions. However, from Jameel's recordings and Jean-Guy's analysis, it appears the predominant tones are in the lower registers. However, most people seem to be more concerned with what appears louder, in the midrange and higher octaves. As an example, your ears notice singers and cymbals, but not necessarily the bass line in any given tune. Look at how much power, the size of the speakers some are putting in their vehicles these days to "feel the music".

It is apparent from Jameel's recordings, plus experience from Ed, Matt, Steve (Woodman), Nako and perhaps others that an insulated, dedicated room type structure does a decent job of killing most of the higher frequencies that seem most annoying. However, I might suggest with the amount of airflow recommended by Pentz, your desired numbers may be unattainable.

But if your family is unhappy from the noise, it might help your case to note your super-duper collection system is keeping dust from going throughout the house.

As an aside, if presented a choice prior to ducting run design, I'd try for the LH unit, for slightly more airflow as the "spin" of the air matches the rotation of the impeller.

As another aside, and not meaning really to dig at Oneida too much, there is an album in the photo gallery where someone switched from Oneida to ClearVue. From perhaps faulty memory, I believe he opined he was unhappy with the performance of the Oneida machine. But that said, for what it is, I can't really fault Oneida, their manufacturing or design. It is just underpowered according the the CFM and flowrates Pentz recommends. And they're pushing a lot of air through a single filter, which means higher porosity at a given filter area (and I also seem to recall, theirs and Wynn's were about the same in area), which in turn means bigger holes in the filter media.

As yet another data point for you, I have one of those older Delta units, with blower on top of a 55 gal. drum and a bag for final filtering, sort of a two stage contraption. At the time, it was highly rated, but in short order, I realized I'd wasted money. At 1 HP, and claiming 700 CFM without ducting or flex hose, it barely got chips once actually connected to a machine. And the 30 micron filter bag just wasn't capturing dust, so I'd go in for the night, and find everything coated the next day. To try to fix that, I, too, bought one of those overhead filter units, this one also Delta. And it works OK. Dust levels in my shop went down, but now after a few years, I'm almost afraid to look in the overhead bins. I'm sure I could have a healthy crop of potatoes up there.

The point being, I've already wasted a lot of bucks on stuff that really didn't do the job. And no telling what its done to my lungs in the mean time. I do know I've developed sensitivities to certain woods, like walnut. Pentz pretty much destroyed his health from being exposed to fine woodworking dust. So although the overhead collector will help, and will cut down on dust that settles throughout your shop, you're still breathing it while working.

You should also be aware you'll need to calculate the bottom line bill, if for no other reason than to put all your choices on an even playing field. Plus you avoid sticker shock and that sinking feeling the pot you've set aside is way too small. You'll need two filters from Wynn, and shipping ain't cheap, though worse for the flex hose. When I cranked my numbers, my bottom line including $400 for an electrician to run several 220 circuits for me, clamps, 60' of SDR-35 pipe, (5) 6" wyes, (11) 45 els, flex pipe and clamps, plus shipping for stuff I couldn't get locally, came out just shy of $2500. Some of it you'll need regardless of whether you choose Oneida or CV. Some may change. For instance, Oneida, last I checked, includes one filter with their system whereas Wynn and CV recommend a pair. But you have to compare full up systems. The "advertised" price is just the starter, like a car without options.

The bottom line for me: Space precluded me from a lot of machines, like Grizzly's or Jet's. I was leaning heavily to Oneida's when I stumbled upon Pentz's site (Google search), which lead me to ClearVue. Yes, CV is a smaller outfit, hasn't been in business as long. But Ed and Matt seem more attuned, more geared towards us hobbyists. Prices, once all is included, are within spitting distance but you get a larger motor and material handling fan with CV. Though Oneida's more aerodynamic fan should be quieter, it also should be cleaned with some frequency and might not do as well if you manage to overfill the collection bin. Plus the clear plastic, though more expensive than steel, adds a "Gee, neato!" factor I find irresistable. So I went with CV. Have the little mini up and running, am pleased with it (surprised at how well it works, actually), and am looking forward to being similarly pleased with the CV 1800.

Hope that all helps.

Regards

DWD