Dust Collector questions.

[paul cottingham]

I have an 800 cfm single stage collector. Can such a machine lift dust and chips 8 feet vertically, 10-15 feet horizontally, then down another 6 feet into a cyclone? Or am I asking too much? I am using 4 inch ABS for the majority of the distance.

Thanks as always,

[Jim Andrew]

You don't say what machines you are collecting from, but IMO, you should use 6" pipe for your main line, and if your machines have only 4" openings, reduce right at the machine. I find that 2- 4" openings about equal 1- 6" in area, so just use one gate on 2-4" openings. My cyclone works better on machines with 6" openings, had to modify my planer as it came with 4", the company literature said to wear a dust mask even when using dust collection, so I just sawed it out and welded in a 6" flange, and it picks up everything. If these WW machine companies would test for dust collection, they would use 6".

[Rod Sheridan]

Paul, 4" pipe is going restrict your airflow to about 400 CFM or less.

To answer your question you need to determine how many CFM you need at the tool, then calculate your duct and cyclone losses.

Once you have the static pressure loss calculated, you can compare that to the fan curve for your dust collector.

It doesn't matter which direction your duct is going, only the static pressure losses are important.

Regards, Rod.

P.S. As a generalisation, an advertised 800CFM single stage dust collector will really only deliver about half of that. I would suspect that it wouldn't be able to cope with the ducting and cyclone restriction.

A good collector will have a fan curve available to provide actual performance curves of the collector, which is required to evaluate performance.

[paul cottingham]

Here is my current setup. I have a trashcan cyclone running into my collector. the cyclone is fed by 4" abs pipe that collects from my table saw, jointer, and planer. It works very well, given the size of my collector.

I am changing largely to free up floor space, currently my piping lays on the floor, in the way. I want to mount it on the wall or ceiling, freeing up floor space.
I have 4" ABS for the horizontal runs.

Am I off my rocker here?

[Rod Sheridan]

Paul, if you keep the same number of elbows, feet of pipe etc. it won't change the performance whether you orient the pipe one way or another.

If you're happy with the performance now, you'll be happy afterwards.....Rod.

[paul cottingham]

I will probably be adding 10-15 ft of smooth ABS. Do you foresee any problems?

[Rod Sheridan]

Probably not............Rod.

[paul cottingham]

thanks. I know this is very vague guesswork,

[Bud Millis]

Paul -

Table saw shouldn't be a problem. The planer and jointer maybe. I didn't see if you listed the sizes. If your using an 8" jointer or a 15" planer, that is pushing the limits of 4" pipe, the distance you want to move it and the suction of the machine (CFM). If its a 20" planer, don't waste your time.

[paul cottingham]

12 " planer little 6" x series delta jointer. my horizontal runs is approx. 15 feet...I use 4" smooth pvc for that. So far, it seems pretty good....but I'm wondering if a 1.5 HP collector might be better (of course it will, but how much?)

I'm also hoping to add in my stuff currently being run off my vacuum, 2.5 inch like my router table, fmt and drill press.

[Bud Millis]

That should do good. You might want to do some mods to the DC - bigger bag, or filter cartridge might give you increased performance.

[paul cottingham]

Ok, i have an additional question, if I may. I now have a 1200 cfm, 1.5 hp DC. It has a 6 in port that is covered by a wye with two 4 in ports. the 6 in. port has a disk welded into it that is essentially a 4 in. restrictor. My question(s) (are) is this....can i cut that restrictor out? Does it need to be there? Would removing it increase my airflow?

Thanks again.

[Chris Damm]

Cut it out and run 6" ducting. Your 1.5HP DC is no where near 1200cfm, they are vastly overrated. My 3HP DC with 6" ducting runs a measured 1250 cfm at the end of a 10' straight section of pipe.

[paul cottingham]

Sorry, i understand that those number are vastly overstated. That is one of the reasons for the question, I am concerned that 6 in. may be too large for effective collection of dust.