Ducting question for DC

[Rob Littleton]

So, I am getting to the point in the shop where I will install my DC and plumb it. I am still stuck with the pipe problem and what to use.

I recently started working for a local plumbing outfit as a driver/warehouse and never realized the amount of choices. One guy even suggested I use what the guy down town is using in his cabinet shop. The like dryer hose stuff and have that hang from the ceiling. Maybe having the main run as the drain pipe stuff (not familiar with the terms yet OBVIOUSLY), then come from the ceiling with the 4 inch metal flexy stuff.......

Any thoughts +ve or -ve on the above suggestion? I was gonna run a ground wire through whatever I install anyhoo.....

I know this an age old question but I am still confused and need to make a decision now.

All my pipe is cost plus 5% so it shouldnt sting me too bad.

Cheers

[Jim Becker]

1) The "ground" wire is unnecessary with PVC/ABS, other than as a drain to help reduce personal discomfort from occasional "little shocks" to your finger if you touch it at just the right moment. If you do "ground", the wire should be wound around the outside, not put on the inside unless you really want to have to deal with clogs from time to time.

2) Use high-quality clear flex hose for your connections and keep them as short as possible. Flex hose has a lot more resistance to air movement and you want to minimize it. There is steel flex available for DC application but it's really expensive. The aluminum stuff sold for dryers is not appropriate and too light for DC applications, especially with the kind of system you're installing in your shop. I like the clear flex from Oneida, but some one recently posted a list of products from various suppliers that were slightly less expensive. Good hose is a bit smoother inside and heavier in construction. It will last longer and work better.

3) If you are still going with the 2hp Onieda Commercial system, keep in mind that the first section of your main duct should be 7" in diameter. You will need to use 26 guage metal for that...no plastic available. Once you reduce to 6", you can certainly use 6" thin sewer pipe quite effectively and economically, especially with your "connections".

4) 4" drops may not be appropriate for many of your tools if you want maximum performance. 5" and 6" works better for almost all of the larger tools and 4" is fine for small tools. Bigger drops can also be used with smaller tools, but not vice versa when it comes to performance.

5) Assuming you go with PVC/ABS, remember that you'll need to use two 45º elbows with a short piece of straight pipe for your bends to approximate the "large radius" elbows available from DC suppliers in metal. The bigger the sweep, the less the negative effect on the air flow.

6) Don't use tees...only use lateral wyes.

7) Don't use those black "dust collection" fittings from the woodworking stores. They are generally poorly made and designed and often reduce the inside diameter of the pipe too much from poor molding.

8) If you buy an Oneida system...get them to design your duct work for free, even if you choose to buy your duct from your employer. They design duct work for a living. Also, read the duct work guide freely downloadable from their site as well as other dust collection resources on the 'net. Educate yourself.

Don't buy your duct work until you have your DC system...you may need to make changes and it's easier to do that before you stock up.

[Chris Padilla]

1) The "ground" wire is unnecessary with PVC/ABS, other than as a drain to help reduce personal discomfort from occasional "little shocks" to your finger if you touch it at just the right moment. If you do "ground", the wire should be wound around the outside, not put on the inside unless you really want to have to deal with clogs from time to time.If you truly want to ground plastic piping, it needs to be done on the inside and the outside. To that end, don't even bother.


Rob, did you see this long thread:

http://www.sawmillcreek.org/showthread.php?t=9933

The kit is fun and challenging to build but I enjoyed it. You also won't find anything on the market that can beat it price to performance ratio.

I haven't decided if I will go plastic or metal ducting for my DC and I will try like crazy to get 6" hook-ups to my TS, BS, and J/P.

[Jim Becker]

Chris, don't even think about not putting 6" to your J/P...you will absolutely need the air flow when working on wide material. This was exactly one of the things that triggered my cyclone upgrade as well as a larger drop to that tool.

[Chris Padilla]

Check, Boss! :)