JDS 3100ck Dust Collector

[Ron Hampe]

Nearly done now my new shop is in our detached garage and this dust collector is located in the lower bay which is 14' x 38' x 13' high. The stairs lead up to the main shop which is 24' x 38' x 8'.

This is a 3hp single phase dust collector rated at 2300cfm. All of the runs will have remote controlled or automatic gates and I will be using spiral pipe, twin 45's or sweep 90's and a minimal amount of flex duct.

Question: A fellow was telling me that I should install an 80" straight duct between the inlet and the first wye if I go with 8" pipe and 60" if I go with 6" pipe. I've not been able to verify that anywhere else and am curious if anyone else knows that to be true or how much of a difference in performance there will be if it is only 36" long?

Looking for opinions and/or suggestions on the design:

This will have a 6" spiral pipe coming off the first wye to the hole that extends thru the wall to an existing 6" pipe that goes straight out to the table saw and wyes off to the center of the 23' miter table located on the other side of that wall.

I'm also planning to run 8" from the side of the wye nearest the stairs vertically thru the ceiling which is app. 8' up from the level of the wye to a 20' horizontal run of 6" across the attic to second wye with a 6" drop thru the ceiling into the center of that bay and a 4" spiral pipe extending from that wye 6' to the outside wall for the twin 4" ports on a 6" x 132" edge sander.

My Oliver 399, Kuster 18" double drum sander, DJ20 and a 20" disc sander are on mobile bases and will have a flex hose with a magnetic connector on each to attach to the ceiling drop. Same will be true for the twin ports on the edge sander.

Not shown but I also have a 1.5hp Delta 50-850 DC that will be dedicated to the cnc and another that will be used when needed for the drill press, band saw and pocket hole machine.

477719

[Jim Becker]

It's always a good idea to have a stretch of straight duct directly to the inlet as it provides for a smoother, 'quieter' air stream into the cyclone. It's not the end of the world if that can't be done because of physical constraints. I can think of no previous mention of a specific length for that straight run but longer is obviously better than shorter. :)

[Bryan Lisowski]

Jim is correct that you should have straight pipe, I think Bill Pentz made a point about this in his write ups about DC.

[Dave Sabo]

I seem to recall the “rule of thumb” is 2ft. of straight pipe before the cyclones inlet regardless of diameter.

And, just who is the “fella” ? Does he have a degree in fluid dynamics , or design ducting systems for a living ?

[Ron Hampe]

I seem to recall the “rule of thumb” is 2ft. of straight pipe before the cyclones inlet regardless of diameter.

And, just who is the “fella” ? Does he have a degree in fluid dynamics , or design ducting systems for a living ?

No clue, just someone who offered his two cents when I posted a question on another site. I hadn't heard that before and when I looked at Oneida's they are only showing 2' of straight going into the cyclone.

[Jim Becker]

Dave, I think two foot is a good minimum if it can be maintained, but longer certainly isn't going to hurt with stabilizing the air stream before it hits the cyclone. Anecdotally speaking, of course...

[Dave Sabo]

No clue, just someone who offered his two cents when I posted a question on another site. I hadn't heard that before and when I looked at Oneida's they are only showing 2' of straight going into the cyclone.


There ya go- some dude -or- one of the oldest and most respected names in the dust collection industry ?



Dave, I think two foot is a good minimum if it can be maintained, but longer certainly isn't going to hurt with stabilizing the air stream before it hits the cyclone. Anecdotally speaking, of course...

Might not hurt the flow, but it might hurt my use of the shop. I've seen plenty of professional designed and installed systems that didn't have 2ft. straight into the inlet too. Like most everything else in life, it's a compromise.