Cyclone & Budget Blower Update

[Bill Pentz]

As many of you know I've been helping Terry Hatfield with his new Dust Eliminator cyclone kit design (http://www.dusteliminator.com) . At Terry's request last week I redesigned my budget blower to instead use a good Leeson 5 hp compressor motor with that Jet 14" DC-1900 impeller. Terry just finished the testing and shared his results with me. I'm both happy and sad.

I'm happy because the new design is clearly an incredible success with performance that leaves even most of the big commercial cyclones in the "dust" so to speak. Here are the real numbers measured with two different sets of calibrated gauges following the test procedures of an independent engineer:

http://cnets.net/%7Eeclectic/woodworking/cyclone/TerryHatfield/FanCurveDustEliminator.jpg

I'm sad because I miscalculated in redesigning my upgraded cyclone plan so others could just easily pick up a standard 4" x 10" to 6" round HVAC transition for the inlet. That saves a lot of work having to figure out how to make transitions, but it squeezes the area down between the cyclone outlet and cylinder wall. That area is a little too small with the air ramp installed and takes a little away from performance. The air ramp does what it is supposed to do in terms of making a very stable airflow, and is needed if you are using an airfoil impeller. For those going with the material movement impellers, like the Jet 14", you should leave the air ramp out.

Here are a couple of additional finds that have come my way that might be of interest for those just getting going on making a cyclone.

The first is the Electric Motor Warehouse (http://www.electricmotorwarehouse.com) is a good source for the motors: Leeson Model # P145K34DB1B, Cat#120554.00, 3450 rpm, 5hp, 7/8 shaft, & 20.8 rated amp motor sells for $179.92 plus face mount #175181 at $15.60 and about $18.54 in shipping. They don't show this motor on their web site, so you need to call their toll free number 1-877-986-6867. To make this work with the Jet you need to order an arbor adapter from Terry or come up with your own. I got one from Terry and am impressed as the workmanship was excellent. I also got from him the 8" flanges for the connections from the blower to the filters, plus some 6" flanges to upgrade a few of my tools.

Second, I recently picked up a set of Wynn Environmental (http://www.wynnenv.com/torit_filters.htm) filters for my cyclone that have good filtering and pricing. Their model 2B226BLFROL is open on both ends, has no inner liner, uses blended, fire retardant filter material, and offers 226 square feet in a 12.75" x 26" cartridge. Two of these works well with a cyclone. I also was told about E-Filter Man's (http://www.efilterman.com/showcat.php?categoryid=2) DF2SOP-254 filter Model# 09080001 that has near identical specifications at only $50.00. Their web page says not yet active and I've not tried to order from them, so may not be a valid price. E-Filter Man also has great pricing on the Farr filters.

Anyhow, that's the latest. Just passing the word as not part of any of these firms.

Bill Pentz
Dust Collection Basics (http://cnets.net/~eclectic/woodworking/cyclone/dc4dummies.html)

[Bruce Walton]

How do you read the graph? Say take the 7SP on the bottom and go up to the 600 CFM mark. It shows 4 SP, too? I'm guessing the 7 SP at 600 CFM sounds reasonable, but what is with the 4SP up the right side? I guess the right side SP numbers completely baffle me. Please help me out here.

[Bill Pentz]

Bruce,

Please forgive. I got a little fancy with my Excel graphing and used a dual scale graph showing both Static Pressure as one line and CFM as another. I replaced it with a graph that matches what others show when they present static pressure and CFM. The scale on the left gives CFM and below gives Static Pressure.

The Static pressure scale is not in nice even increments as the testing was done using a series of different sized rings. Each ring generated a different pressure. To get nice even increments, I would need to put in a blast gate, tweak that gate until I got the static pressure desired, and then get the CFM from that.

Regardless, the bottom line here is that even with the extra overhead of pulling through a cyclone, this unit absolutely kicks tail in terms of the CFM it moves. In the working static pressure range which for most hobbyist sized woodworking shops will range from about 3.5" to over 10", this combination will do the job and get the fine dust that lots of others claim, but don't move enough air to get the job done.

Hope this clears the confusion.

bill

[JayStPeter]

How did that compare with the $99 HF "5HP" compressor motor?

Thanks

[Scott Coffelt]

How much do you suspect I will see in difference in performance if I have already attached and sealed the air ramp? I plan on using the PSI 14" 2Hp blower. I really do not want to tear this thing apart considering that I have went to a bunch of trouble to assemble and seal. I am at the point where I am attaching the cone to the upper cylinder.

[Bill Pentz]

Jay,

The HF motor should get exactly the same results as the Leeson motor. Both are rated near identically, but the Leeson is a much heavier motor with bigger bearings and an easier to use face mount. I personally have a Baldor, HF, and Leeson. Of the the three, I favor the Leeson. The Baldor is a little more quiet, but my motor expert said the Leeson is actually a little better for this application.

Scott,

I have measurements both with and without the air ramp. I calculated the % difference at the various static pressures to see how much impact:


SP Difference
3.8" 11%
4.3" 8%
6.8" 3%
8.5" 4%
9.1% 8%
9.7% 2%
10.4" -17%


With our systems designed to work in the 4.5% to 9% range, I don't see this as a significant effect.

The key point here with the air ramp is it does reduce buffeting and flow problems that make your blower oscillate. For an airfoil this is important, and is not for a material movement impeller such as the Jet. Bottom line, if you have it built, don't worry about it, you are still going to have double the airflow of anything else I've been able to measure and plenty to collect that fine dust at your larger machines.

Please let me know if you have more questions, and my sincere apology for the confusion here.

bill