Poly liner for 55US gal steel chip collection drum on cyclone dust system?

[ian maybury]

I'm nearing the end of building a Pentz/Clear Vue style dust system. (my thanks to Bill for his work, and CV for the bought parts which have been of excellent quality) It's running. Boy do these systems move some air!!!

The non standard layout (blower mounted in a loft, cyclone projecting through the floor) permits the use of a std 572mm dia X 851mm deep 55gal open top steel drum for chip collection - in place of the usual trash can size. The plan is to use poly bags for chip disposal. There's build photos on this UK forum here - two batches, one near the start, and another towards the end of topic: http://thewoodhaven.co.uk/phpBB3/vie...php?f=3&t=2048

Finding an off the shelf source for small quantities of polyethylene drum liner bags is proving difficult in Ireland (it's a very small market) - no problem if you can order 2,000 and can wait four weeks for them. The ideal item is probably a circular bottomed drum liner in heavy 125 micron (?) polyethylene, but so far they can't be found in small quantities off the shelf. An option is possibly a gusset bottomed 900mm wide (when flattened, that'd give circumference of 1790mm) bag, but it's again proving difficult to find these in a suitable size.

Can anybody suggest a standard bag that would suit, and name the application they are used in? This might help the search over here.

Are liners like this available off the shelf in the US on a mail order cash sale basis? (I'm sure they are)

Experience based input on the pros and cons of bag types, and on how to handle them/what to look out for when using them for dust disposal would be appreciated. I'm presuming they work well provided the drum lid is well sealed so they don't get sucked up into the cyclone (I have clip on lids with built in seals and full circle clamping rings), but don't know if the lids will seal well enough if I use an oversize bag that requires folding of the polythene to fit it in.

The thinking is to use clears bags, and fit a perspex window in the side/top section of the drum, plus another in the lid for shining a light through so that the level can be checked. Is this likely to work?

Thanks

ian

[Rod Sheridan]

Hi Ian, no help to you however in Canada you can buy a box of drum liners at most cleaning supply places, or Home Depot etc.

Perhaps you could check at places that sell commercial cleaning supplies in Ireland?

I use the drum liners in a 35 gallon drum (Oneida cyclone) and can barely lift it when it's full of sawdust. It's Ok when full of planer shavings, however sawdust is much denser.

Regards, Rod.

[Jamie Buxton]

A window in the side of the bin is a very very good thing. If you don't notice that the bin is full, eventually all the chips are flowing into the filter. Cleaning the filter is a big pain.

Just dropping a flexible bag into the bin doesn't work. It gets sucked up into the cyclone. If you're going to use a disposable liner, you need more robust means of holding the bag down. I've never seen one I really like, so I don't use a liner. Instead, chips go directly into the bin. When the bin is full, I empty it into the dumpster, or into plastic trash bags to give to gardeners.

[Jamie Buxton]

In the US, you can buy almost any size and shape of plastic bag from U-line. Dunno if that really helps you though. www.uline.com. They're kinda set up so their minimum buy is $100 or so, so you'll likely get 100 or 200 of any bag you buy.

Rod's point about the weight of a bag filled with sawdust is a good one. When I fill 35 gallon bags, I'm always in danger of ripping them or poking holes in them.

[John P Clark]

I use these for my 55 gallon drum from my Oneida cyclone http://www.uline.com/BL_6754/Round-Bottom-Drum-Liners Like Rod says these are very heavy when they are full of sawdust, and the bag gripper has pulled them tight against the drum

[Prashun Patel]

I wonder if you can use any kind of clear plastic or trash bag, and then use a wire retainer ring to keep it from collapsing.

[Rod Sheridan]

I wonder if you can use any kind of clear plastic or trash bag, and then use a wire retainer ring to keep it from collapsing.

Prashun, that's esentially what I do.

I made a "birdcage" with a top and bottom ring and four vertical slats out of that steel strapping that holds things onto pallets. It has almost no thickness so it isn't messy to pull it out of the bag/drum before removing the bag of dust...........Rod.

[Jamie Buxton]

Here's my take... Unless you have an industrial-sized disposal means, a 55-gallon chip bin is too big. 55 gallons of chips makes an object that's too big to handle easily. It is heavy and bulky. It will overwhelm the usual disposal systems in US residences. 30 or 35 gallons is much more manageable. You can more easily pick up the bin to dump it. Or if you use a liner, you can more easily handle the bag full of chips, and the garbage collectors can handle it too.

I think the 55-gallon approach comes from the light-industrial environment, where big dumpsters and forklifts are more common.

[Jeff Monson]

Here's my take... Unless you have an industrial-sized disposal means, a 55-gallon chip bin is too big. 55 gallons of chips makes an object that's too big to handle easily. It is heavy and bulky. It will overwhelm the usual disposal systems in US residences. 30 or 35 gallons is much more manageable. You can more easily pick up the bin to dump it. Or if you use a liner, you can more easily handle the bag full of chips, and the garbage collectors can handle it too.

I think the 55-gallon approach comes from the light-industrial environment, where big dumpsters and forklifts are more common.

I could not agee more, I've dealt with a couple 55 gallon containers full of chips, its a major PITA, I'd much rather deal with a 35 gallon container any day of the week and dump it more often. Just my .02

[ian maybury]

Thanks guys, as ever you've come up trumps. Fortunately I'm at a stage where it's possible to go whichever route works best.

On weight. I've been used to using a much smaller bag/filter unit, and the bag on it was indeed quite heavy when full. Think maybe I'll try the 35 gal option first as the bags will have to be hauled across a small yard to a trailer.

On drums. Since posting I've discovered I can get fibre drums in a variety of sizes from a packaging supplier, and that I can probably fit a ring clamped lid on the bottom too. The parallel sides should help in getting the bags out, especially if the 'unclamping the bottom and lifting the tube (that is the drum wall) off the bag' method I'm starting to remember somebody saying they use works.

On bag holders. My head is indeed shot. I'm also starting to recall a discussion on the various methods here (?) maybe a year ago - including the arrangement OA have on some of their systems that takes a tapping from a low pressure location on the cyclone to pull the bag into the drum. Others (including maybe yourself Rod) mentioned various mechanical hold downs.

I had thought that the bag would stay put in the drum if it was well sealed, although this looks a more risky proposition now that I've run the system - it's actually generating a fairly decent level of suction inside the cyclone. The drum would need to be very well sealed to prevent enough air bleeding in and getting behind the liner to cause a problem. (leakage presumably isn't good for the fine dust performance of the cyclone anyway, in that it'd prevent it from dropping down the hose into the drum)

It sounds like a mechanical hold down works well - something rock solid reliable that can't fail is attractive.

Those Uline guys are exactly what's needed over here. Will have to keep digging. Maybe switching to a 35 gal drum will open up some local options on bag supply...

ian

[Tom Rausenberg]

I put a window in the top of my rectangular bin, and it works well. Just shine a flashlight in there, and you can see when it's full.



Picture120.jpg

[ian maybury]

Thanks Tom, good to hear that....

ian

[ian maybury]

Just to say I ran a source of 500mm dia X 810mm 35 gal fibre drums to earth this morning. Not only that, but they also had liner bags available that fitted perfectly. Off to install windows and hook it up now.

ian

[Alan Schaffter]

Ian, I'm sorry, I'm late to this thread, I thought it was about a ClearVue instead of a DIY Pentz installation, but if your drum and liners don't work the way your want and you are up for a few mods- here is a solution- reconfigure you cyclone as a "push-through' with the blower forcing the dusty air into the cyclone rather than pulling in through. Then, all you need to do is attach any sort of bag directly to the bottom of the cone with a band clamp.

That is how my system is set up. When the bag is full it is easy to disconnect it, tie it off, and put it out with the trash. Since air is being forced into the cyclone the bag will be under positive pressure and not collapse, and as long as you don't have a totally clogged filter, the pressure won't cause the bag to blow-out, at least not with my 3 hp motor / 14" impeller blower unit- and I've tested that by over-filling the bag and clogging the filter on numerous occasions before I designed and added a high dust alarm.

My cone may look longer than the ones on a typical Pentz cyclone, because it is. It is a 3D- length of the cone is 3 times the diameter of the cylinder, not 1.64d like a standard Pentz. (I've never tested it so can't prove it, but a 3D is supposedly better at separating fines than a 1.64D)





The twin filters mount in a plenum above the cyclone. Plenum was not installed when this photo was taken.



Standard 39 gallon leaf and lawn bag:

[Jamie Buxton]

... reconfigure you cyclone as a "push-through' with the blower forcing the dusty air into the cyclone rather than pulling in through....

Back when I had a cheap bag-type DC, it was a push-through. If all that ever went through the thing was dusty air, it worked fine. But hand-plane shavings would wrap themselves around the impeller, and force a tear-down to get them out. And little solid-lumber offcuts would bang through the impeller like a grenade. IMHO, one of the great things about cyclones (of the usual pull-through design) is that they don't require babying.