My bin is empty, but at least the filter box is full!

[Nathan Conner]

So, after using the new-to-me cyclone for a couple of months and rapping on the barrel every so often, I decided it was time to clean it out, regardless of the hollow sound.

Imagine my joy on finding a perfectly clean, empty barrel. With a sigh, I gathered the tools to start taking the filter box apart. What a MESS! The entire filter box (7' x 3' x 3') is full to the brim with chips, dust, crud. There were several families of beavers living in there, a smallish herd of white-tail deer, and two families of gypsies that had tunneled out some living space.

So, apparently, something's wrong. I cleaned and cleaned and cleaned, got the entire box emptied and disposed of, even gave the gypsies a few bucks to relocate, though I will dearly miss the fiddle music in the middle of the night. (I'd often wondered where that was coming from)

I fired the cyclone back up and went to town with the incense, all around the opening below the cyclone. The 55-gal drum is steel, has been ground smooth and free of rust around the edge and lined with closed-cell foam tape. There's a metal retaining ring with a long bolt to really crank it tight (enough to hold liquid) and about 230 layers of duct tape around the bung hole that had been tapped into the steel top. The 6" flex hose is tight to the bottom of the cyclone AND to the steel barrel lid. With it running, there's no disturbance of the incense smoke. No "barrel gets sucked into the air" deal, but it seems plenty tight. Without the barrel attached, I feel my arm wanting to get sucked up into the cyclone.

Is it possible that there's something wrong with the design of this cyclone? There's nothing stuck in the air ramps, the 5hp motor hums away, it sucks like crazy and I have great collection at the tool-end of things. I bought this custom-built Pentz designed cyclone from a Craigslist post, and though it was noisy, it seems well-put-together. Strong steel, good welds, good spray-on liner inside. There's a 10' mostly-straight run up to the cyclone. It had never been used (it was too noisy for the neighborhood) other than to test it.

It seems I recall thinking the foam seals between the impeller and top of the cyclone seemed rather beat up when I was assembling it. Is that a possible issue? Could something be silly like the vanes welded backwards or the motor wired backwards or...something?

I want to make sure before I build a custom top for the drum or buy a new drum/top kit. Should I try installing a bag, and see if it gets sucked up into the cyclone?

It makes me sad.

[Doug Shepard]

No expert but I think the problem is air leaks at the barrel lid. Ed @ ClearView emphasized that I needed to ensure I had a good gasket to seal it up. I think the problem he described is the mess you have.

[Phil Thien]

With the type of problem you're having the leak would be sufficient enough to move the smoke. You may want to repeat that test, just make sure you check the entire drum (top to bottom).

The vortex finder tube (the tube that extends down from the motor into the center of the cyclone) isn't missing, is it? How far into the cyclone does the vortex finder extend?

[Alan Schaffter]

I think Phil is on to something. There is something major wrong with that cyclone. Even a leaky cyclone will separate 80% of dust. Either that or it is connected wrong. Any pics of outside and looking up into the dust outlet?

[Don Abele]

Guys, I don't have a cyclone and don't pretend to know that much about them other than I know they work much better than my Jet DC-1100.

Anyway...why would he feel suction at the discharge where the dust barrel attaches? That doesn't sound right because that's where all the dust should be dropping in to. If there's a suction there, it would never fall into the bin.

Does this sound right...and if so...how?

Be well,

Doc

[Alan Schaffter]

Guys, I don't have a cyclone and don't pretend to know that much about them other than I know they work much better than my Jet DC-1100.

Anyway...why would he feel suction at the discharge where the dust barrel attaches? That doesn't sound right because that's where all the dust should be dropping in to. If there's a suction there, it would never fall into the bin.

Does this sound right...and if so...how?

Be well,

Doc

The whole cyclone is under suction (unless you have a push-through like mine). That is why the dust discharge chute and barrel must be tightly sealed and the barrel wall heavy duty enough so it won't collapse. With a sealed chute and barrel there is no flow in or out of the barrel and the dust can fall into the barrel via gravity.

[Tom Veatch]

...Anyway...why would he feel suction at the discharge where the dust barrel attaches? That doesn't sound right because that's where all the dust should be dropping in to. If there's a suction there, it would never fall into the bin....

That is completely normal. The impeller draws air out to the cyclone body reducing the pressure in the body. Air under higher, atmospheric pressure enters the cyclone body through any opening it can find. Normally that opening will only be the cyclone inlet.

But, if the dust outlet at the bottom of the cyclone body is open, air will try to enter through that opening as well as through the air inlet at the top of the cyclone. That will be detected as "suction". Normally air cannot enter the dust outlet since it is connected to a (presumably) sealed dust collection bin. Therefore, there is no airflow into the cyclone through the dust outlet. And note, it is airflow, not pressure differential (suction) that affects the dust particles.

With the dust outlet sealed to the collection bin, the bin and the cyclone body will be at the same (reduced) pressure. Hence there will be no pressure differential between the bin and the cone to induce airflow into the cone. No airflow, no effect on the dust dropping out of the bottom of the cone.

Incidentally, for those who use can liners/bags in their bins and have problems with the bags being drawn up into the bottom of their cyclones, it's because there is an air leak in the bin allowing air to enter between the bin wall and the bag. If the bin is well sealed, the bag will not be drawn into the cyclone cone.

[Alan Schaffter]

And that is one of the reasons I built my cyclone in the "push-through" configuration.

(The chip bag is under more pressure here than usual because I hadn't cleaned my filters after a major back-up. Two years ago I did some heavy planing and didn't check my bag which is not in my shop, so dust overfilled the bag, eventually backed up into the cyclone, and then into the filter. Immediately after this "latest" backup I installed the high dust detector visible it this pic. It has worked great since then, by the way)

http://www.ncwoodworker.net/pp/data/500/HighDust-9.JPG

[Bret Leishman]

Allen, could you provide info on your high chip/dust detector?

[Alan Schaffter]

I don't want to hijack this thread, so here are links to my High Dust Alarm threads on NCWW. The first covers my initial ideas, pics of the parts and installation, and was updated with test results. The second contains a simple schematic and installation diagram for bin type cyclones, and the third is a write-up with pics of a portable version (in a fancy enclosure) that I made for a friend.

Please note there are many identical/nearly identical photo-electric sensors on the market- this one (Summit Lighting CP688 I purchased at Lowes) is the only one I know that works properly. Others that look identical, some even from the same manufacturer, have an internal resistive circuit inside instead of a relay circuit and so have a delay, which can be as much as three or more minutes before actuation. Read the product description first. If it says time delay anywhere, I do not recommend you use that sensor!

High Dust Alarm, It works!!! (http://www.ncwoodworker.net/forums/f31/cyclone-high-dust-alarm-works-w-new-pics-7195)

High Dust Alarm and recommended installation on cyclones with a dust bin (http://www.ncwoodworker.net/forums/f31/cyclone-dust-alarm-circuit-w-sketch-7240)

Portable Dust Alarm- Oneida test (http://www.ncwoodworker.net/forums/f81/portable-cyclone-high-dust-alarm-w-pics-13220)

[John Schreiber]

Based on your description, nothing comes to mind. But, I wonder if something is installed backwards or perhaps a major piece is missing. Perhaps if you posted a couple of pics some one here might be able to identify the problem.

I wonder if the problem with the previous owner was really the noise, or did he have the same issue you did?

[Nathan Conner]

I wonder if the problem with the previous owner was really the noise, or did he have the same issue you did?

If he did, he did the vary smart, sane thing, and got out of woodworking altogether.

Let me just say, I feel stupid...REALLY stupid. But not SO bad, because no one suggested it.

Let me start by saying that when this first happened 3 months ago, I thought it was a leaky top. I fixed that. Then, it happened again. I thought it was more leaks, so I ground the rim of the barrel smooth, bought some camper tape and put new tape on the lid for a nice tight seal.

Then, it happened again, so I replaced the thumbscrew on the retaining ring with a huge lag bolt, and used the air drill to really hammer it down. I'm surprised I didn't collapse the entire steel drum.

So, after this last go round, I'd had it with this steel drum. Obviously it doesn't work. There's SOME issue with it. I tore it out, threw away the 6" flex hose connecting the bottom of the cyclone to it, and found a guy locally in Portland, here, who sells barrels. That's ALL he sells. Thousands of them, all shapes and sizes, all used. He showed me a great reinforced fiber drum with a quick release retaining ring on the tough plastic lid. It has been used to store a bag of 600 lbs of liquid, so I figured it was good enough. $10? I'm in! (Let me know if you want a cheap drum source in Portland!)

I brought it home tonight, did a SUPER careful trace/cut job on the bottom of the cyclone -> lid mating. It's PERFECT. Just in case, though, I used about 1/3 gallon of silicone.

I thought to myself, "Self, you'd better do the underside of the lid, too, for overkill!" So, the lid's hanging in midair, connected via hole to the base of the cyclone. I'm on my hands and knees under the cyclone, looking up, caulking gun poised...

...poised... (*blink*) ... (*blink*) ...

There was about 5 seconds of open-mouthed silence.

Then I got the camera and snapped the first photo - evidence of my idiocy.

Then I reached up and carefully pulled out the first of the handfuls of 20" cross-grain walnut planing fibers that were...of course...jamming the bottom of the cyclone about 10" up.

After about 8 handfuls, a WATERFALL of dust and chips cascaded out of the bottom of the funnel. Then I took the second picture.

Gee. I wonder what the problem could have been?

(*facepalm*)

[Nathan Conner]

Any pics of outside and looking up into the dust outlet?

And Alan, I owe you a cold one. Had I listened to you in the first place and taken the picture, I would have figured it out.

(*sigh*)

[Alan Schaffter]

And Alan, I owe you a cold one. Had I listened to you in the first place and taken the picture, I would have figured it out.

(*sigh*)

Glad I almost helped! :D By the way, take a look the second sketch at the second link in my previous post. It is a good way to set up your dust drum so it doesn't fill all the way to the top. Of course, you could also build my high dust alarm too. :D

[John Eaton]

Hey Alan,

Thanks for posting those links. I may try to build one this weekend if I have some time and I'll post what I come up with. Has anyone tried using an LED for the light source successfully?

-- John

[Alan Schaffter]

I haven't heard of anyone using an LED.

A number of NC Woodworkers have built my high dust alarm, as has Todd Crow, a member here, and all have used incandescent bulbs. I get 6 mo. or more life from the 7W bulb I use. Also, you can always go to a higher wattage bulb if your window or clear flex duct gets cloudy and the sensor needs more illumination.

FYI, please read my bolded red note about the proper sensor. They may be getting harder to find because I think they are actually being replaced with the ones that have a time delay to reduce/eliminate flicker that the older relay types exhibited. Most of the Intermatic models and some Summit Lighting models at the big box stores have a time delay.