Replies

1. 
   sawduster | Jan 10, 2004 06:21am | #1

   I'm using 2-4" PVC trunks on a 1.5 hp Jet DC. I find it is adiquite so long as I only use one machene at a time. The only thing that seems to not function well is the band saw which has a 4" flex and a 1 3/4 connector. I just finished resawing some vineer and had dust all around the saw. Other than that, the jointer, table saw, drum sander, and router table all work well. So far as explosion hazards, if you use a bonding wire you should be okay with the PVC, especally if you live in a humid climate (humitity at or over 50%).

2. 
   hammer1 | Jan 10, 2004 07:03am | #2

   Dust collectors can be funny. If you are a math wizzard you can calculate all types of values, pressures, static lift, and figure each elbow and fitting but the fact is as you said, you don't run all the machinery at the same time. You need blast gates and how you operate the gates and what they open to will often affect the collectors efficiency. Standard shop equipment, table saws, shapers, etc. usually have 4" outlets so I run 4" to them. Small stuff can have all different size fittings needing adaptors and reducers. I like the clear flexible hose, easy to find fittings, easy to find clogs and quick to move around for special uses. My table saw and planer have 4" outlets with a run of 5ft. to the saw and 20ft to the planer. 2hp, 2bag, 6" into twin 4". I can run both of these with just the line to them open and the collection is great due to their wide open hoods. If I run my shaper or joiner with just their gates open the collector moans for more air so I just crack another gate. Generally the farther away the smaller you want to be so with your collector I would not run a big 6" out 30ft. If you want to run 6" for 10ft. with a bunch of Ts then drop to 4" I think that would work with out losing too much just to the pipe. With your collector you will have two elbows just to get to the ceiling and you won't be able to move it if you are hooked with ridgid pipe. I have set up and run some rather elaborate engineered industrial systems, 16" pipe to start, and they react similarly. Static electricity does build with plastic, my hoses were real hairy today, 20 below and dry as a bone. As far as exploding schedule 40, maybe if you planed enough wool and silk. You can ground everything easily. We've all heard it can happen, sounds like a job for the myth busters. Listen to your collector, it will talk to you!

3. 
   TerryH | Jan 10, 2004 07:14am | #3

   cutawooda,

   The SF will support 6" ducting, right to the tool just fine. I had the Griz 1029 before I built my cyclone and it performed well. Definitely get some good bags!!!

   I would suggest that you run the 6" as far as you possibly can reducing only right at the tool. I have even upgraded many of my dust hoods on my machines to 6". The 6" makes an amazing difference.

   This whole deal is about moving air. Bottom line is 6" duct will flow about twice as much air as a 4" duct. The larger duct is the way to go as long as you maintain duct speed sufficient to keep the dust suspended in the airstream. The SF has enough power to keep the duct speed up where it needs to be in the 6".

   PVC is very unlikely to blow you up. It has been in my shop for quite a while and I couldn't be happier with it.

   More on my site if you are interested.

   http://www.terryhatfield.com

   Terry

   Registered Shopaholic
4. 
   kensshop | Jan 10, 2004 04:41pm | #4

   Terry H is entirely correct.  I also have a Jet 2 hp system with an aftermarket cyclone.  Run the 6" as a trunk to the very last machine.  Split off with 5" down to the machine then use an appropriate reducer.  This will maintain maximum air flow right to the machine's dust outlet.  The comment about goods bags is also important.  Incorporate a cyclone as this will help maintain the bags' ability to "breath".   PVC?  I used metal but PVC is fine as long as you follow the rules about keeping it grounded.      Good Luck!  Ken

5. 
   triplenet | Jan 11, 2004 03:01am | #5

   Hi,

   I have a Torrit with 2HP.  I ran 6" metal snap duct as a trunk line (taped all seams and joints).  I used PVC plumbing for Y's and reduced drops to 4" metal snap duct.

   I installed metal Jet blast gates at each machine and it all works well.  I did a floor sweep, but hardly use it as it's easier to make a few piles rather than sweep a big amount to the sweep.

   I also recommend the remote control (Penn State?) can't remember the brand I bought, but it's well worth the bucks.

   Good luck.

6. 
   dirtstirrer | Jan 11, 2004 08:54pm | #6

   I went through the DC mind convulsions this fall, and someone here recommended this link.  Its got some great info, and a bunch of it.

   http://cnets.net/~eclectic/woodworking/cyclone/index.cfm

   aka Steve
1. 
   RandMCapozzi | Jan 12, 2004 04:30pm | #7

   Check out Bill's site (http://cnets.net/~eclectic/woodworking/cyclone/index.cfm) as Steve suggested. After looking through it (a lot of information) you will know more than what you need to figure out the correct size of your duct work. I found his site extremely helpful when figuring out my setup and debunking some DC myths.

   --Rob

7. 
   GHR | Jan 12, 2004 10:15pm | #8

   There are two things you want to accomplish.

   You want to pick up and carry the dust. There is a minimum speed for that.

   You want to NOT blow the fine dust through the bag. There is a maximum speed for that.

   I suspect 3" pipe is a good size to do both for your application.