Replies

1. 
   shawng | Oct 14, 2009 06:19pm | #1

   I have an "engineered" basement floor, meaning that it's suspended on steel and aluminum beams and a crawlspace underneath.  I considered routing my DC under the floor, but decided against it.  I figured that making changes would be much more difficult if I moved machines, and I also worried about removing any clogs, especially in the bends of the pipe.

2. 
   Jammersix | Oct 14, 2009 07:25pm | #2

   In my opinion, much easier to go overhead. I used 4" ABS, working fine.

   Hanging piping from the ceiling is MUCH easier than a raised floor, and you will find that a 9 foot ceiling is a wonderful thing in a wood shop. Don't do anything to lower it.

1. 
   zolton | Oct 16, 2009 03:28am | #7

   Jammer,

   That's the best, shortest advice I've ever read on this forum! And I agree 100%. The ceiling height issue is a big one, especially for spinning around sheets of plywood..

   ZoltonIf you see a possum running around in here, kill it. It's not a pet. - Jackie Moon

3. 
   Don01 | Oct 14, 2009 07:27pm | #3

   Our favorite topic.

   If I read correctly, you are thinking of sizing your ducting to your flooring. Simply put - Don't!
   1. Your entire DC system needs to be sized to accommodate your dust generating tools.
   2. If you don't like your tool placement, your ducting will be buried, forcing you to use inefficient flex hose to connect your machines.
   3. You will find that you under estimated the duct size. Putting lrger ducting in the flor will not be an option.
   As this system will be in your home, you have to be extra cautious about not contaminating your living area.
   First get yourself up to speed on dust collection. There are a number of resources including the online archives in these forums.
   One of the best is:
   http://www.billpentz.com/woodworking/cyclone/index.cfm
   You don't have to agree with his solutions but you will get a good understanding of the basics and will be able to make better decisions.

   Don

4. 
   stevecater | Oct 14, 2009 09:18pm | #4

   I have a stand a lone shop, 5hp cyclone (home built), 10' ceilings but I have a 2x8 joist floor with another 8" clearance below the joists to the gravel floor.
   As such I have lots of space between the joists and also under the joists to travel across the floor where needed. My cyclone is in one corner and the pipe for the south wall runs on the wall then a wye takeoff sends it under the floor. From there I supply the north and west walls rather than go overhead. It is the shortest distance between points as well so cuts down on total duct run. I branch off to supply the jointer, TS, BS and other items as needed all UNDER the floor.

   I had the same shop piped with overhead at one time so I can compare from experience.

   Given the room I MUCH prefer under floor for a few reasons.

   - Pipe overhead casts shadows unless your lights are suspended below and it sounds like you don't have that option with 9' ceilings as your lights would really be low then.

   - Overhead pipe was often in my way weilding long boards etc.

   - Exposed plastic pipe is a dust magnet! I hate the 'chia pet' look;)

   - Pipes on the wall take up wall space (always a negative)

   Under floor (given room) is out of the way has some nice points primarily the opposites of that listed above.

   As for clogging, I have not had a clog in 6 years either overhead or under floor. That said, leave a wye or just take off the fitting where it exits the floor if you ever need to snake out a pipe, not a big deal.

   Your setup sounds like you don't have room to install 6" duct which would be the choice for most 2hp DC and up. 2x6 sleepers only leaves you 5.5" and that's too tight for 6" so in the end you probably are going to have to go above ground.

   Cheers,
   Steve

5. 
   stevo1952 | Oct 14, 2009 09:36pm | #5

   HI Todd,
   I really think its a good idea to put dust collection and also wiring below the floor if possible. Of course you may want to move things and clean out clogs etc. so what I would do would be to put in some removable panels of plywood or corrogated steel that could be lifted out to access the pipes. I had installed some 4" lines for my table saw in concrete, and while it works, next time I would allow for at least 6" or even 8" and use the wide bends, not the sharp ones that plumbing usually has. Good luck. Stevo

1. 
   Jammersix | Oct 15, 2009 01:00am | #6

   The main thing to remember is that FWW solved the round dog vs. square dog, finally, and once and for all.