Just thinking about a full on system... Design idea at work here...

[dbhost]

The thought occoured to me that the impeller housing / blower motor can be integrated into the lid of a Thien cyclone, and eliminate much of the resistance of the feed hose. So with my brain churning along I want to present an idea here to you guys and gals...

Start off with a known good blower motor. PSI sells some decent ones with 14" impellers, 6" inlet (and presumably 6" outlet).

http://www.pennstateind.com/store/DC250SEMB.html is the one I am thinking of. A bit pricey, but would work. Other suggested makes and models would be appreciated.

A 55 gallon drum like the one I used in my recent build.

http://www.jpthien.com/smf/index.php?topic=223.0

Side inlet as seen in so many other builds...

http://www.jpthien.com/smf/index.php?topic=196.0

With the DC on top of the lid. (Not quite like in this pic, using the side inlet should eliminate the need for the riser from the lid...

http://www.jpthien.com/smf/index.php?topic=27.0

Wynn spun bond Farr style open / open filter. Sorry no pics...

The question would be how do we connect to the filter, and provide for the inevitable amount of dust that gets past the separator section?

Commercial cyclones have a short jumper of hose, that leads to the filter assembly, with a catch pan below that on the floor.


Is there a better way of doing this?

Is this worth doing? How would the results compare to a commercially available cyclone?

[Sub-Dooood]

The first thing I notice about your plan is you'll have about $500 into it just from the blower and the pleated filter.  I don't know what a 2hp cyclone costs, around a $1000 or so?  I think you could get very good separation efficiency, especially with the tangental (side) inlet, if you paid very close attention to the tolerances you cut and fitted the various parts to and made sure you sealed all air leaks.  The large 55 gallon drum would be more tedious to empty than the smaller fiber drum under most cyclones.  Lifting the combined assembly of the blower housing AND the drum lid/baffle to empty the barrel would be a pain, as well.

That being said, as to the configuration: I would set the drum and the filter side by side, kind of like the cyclone from JDS.  Feed off of the blower housing with a short length of flex hose to an adaptor disk on top of the filter.  On the bottom of the filter, put a sealed box with a smallish clean-out tray.  Both the barrel and the filter assembly could ride on a common platform, but that would have a rather large footprint (if floorspace is a limiting factor).

Just shooting some random thoughts back at you.  It would be an interesting project and my gut says you could more or less equal the performance of a commercially available cyclone for somewhat less money.

[servant74]

I saw on the Woodwhisperer site he has a ClearVue cyclone, and the exhaust of the blower goes through an MDF built up duct directly into the top of a filter stack.  Using a solid duct that keeps down the friction should allow the air to blow smoother and dust not to collect in the creases in the hose.  Even a plastic hose or pipe would be OK here, and the smoother inside, the better.

I was thinking that using a 55gal drum or even a large metal trashcan would be nicely served as the chip collector.  But putting the fan and top 'on and off' could be a pain.  Making a 'short table' that the can or drum can sit on, with a simple lever to 'raise and latch' the empty drum or can in place while allowing it to be slightly lowered (half an inch or so?) for replacement might be a neat option.  That way the blower / chip separator could be stationary.

Reading the Pentz site for a 'long' time gives some insight as to why he chooses a 5HP blower and 14 to 16" steel impeller (like you get with ClearVue) similar to what Jet has on their larger units.  It is that a small shop full of tools requires it.  He has lots of information about calculating it all, and the size of 'vacuum bubble' needed around various tools.  The size of the 'bubble' and the speed of the air needed to collect the fine particles determines the number of CFM needed.  In addition to that, there are friction losses, leaky blast gates, etc that all need to be considered, plus you should never close all the blast gates (you will starve your blower of air)... anyway, Pentz helps you calculate it all and also has a 'short cut' rule of thumb.  A small one man shop with one or two major tools running at once will have around (or under) 200' of ducting, and to run the amount of air needed, typically needs 6" duct, and to keep that all moving fast enough it requires just under 5HP with a well designed blower.

Using Bill Pentz rules, 2HP blower is about right for some tools, but wouldn't cut the mustard to power even a small shop with his kind of desired specifications.

Would a 2HP unit work?  Obviously the answer is yes.  Bill Pentz would suggest it still needs the find dust collection filters on it.

Bill Pentz has major health problems caused by his long term wood working as a woodworking professional.  So his focus is NOT the large particles that his cyclone and the Thien Cyclon Separator Lid collects so well, but the fine particles.  And to Bill, you need to collect particles down to half a micron to keep the air 'healthy enough.  That is why he suggest filters like Wynn sells and that is why ClearVue (which uses the Bill Pentz design for their cyclone, just implements it in plastic) uses the big filters that are rated to the half micron level and has LOTS of filter material, partly so it doesn't need to be replaced so often and it allows enough air to come through without generating a lot of back pressure across the filter.

Sorry for being so long winded.