[woodpig]

I have recently purchased a 2 hp dust collector from Harbor Freight for my small basement shop. I am planning on hooking up my new Grizzly table saw (when it arrives), my router table and my miter saw to this system. This should require less than 20' of ductwork, I was planning on using 4" metal ducting from Menards or Lowes, and clear flexible tubing just for the tight/difficult spots. However, I just discovered that I can purchase a roll of 50' of 4" clear flexible tubing on eBay for about $60.

What I'm wondering is this -- is there any good reason for me not to skip the metal ducting and just use the clear flex tubing for the whole thing? It would save me some money, it has good user reviews and it even claims to be "self-grounding". I'd even have a bunch left over for when I eventually want to add more machines to the dust collection network.

Thoughts? Feel free to tell me if this is a dumb question, but do it gently if you have to...

 

[Stick486]

flex will cost you efficiency...

 

[RainMan 2.0]

I’m with Stick . In order for it to flex, it’s going to have ribs . I’m my case, I want every available cfm I can get .
Now if we’re talking clear sewer pipes , that’s another story .

 

[woodpig]

Okay, thanks guys, that's the information I needed. I'm going back to my original plan; flex only where necessary.

 

[DaninVan]

Bryan; I'm in the same boat right now...the Wonderful World of Dust Collection piping. meh...
I discovered that:
-the ID of 4" PVC drain pipe is the same as the OD of dust collector fitting hubs , ie it's a tight slip fit. This means that if you use a short piece of the pipe over the ftg. hub, the other end of the pipe piece will now be a perfect fit for the hubs of PVC drainage fittings and/or the flex hose (with a gear clamp of course. So, short story, cheaper fittings, better and easier to find selection.
-somewhere in the archives here there's a thread on customizing PVC pipe and fittings using heat, if you like the PVC idea. Not going down the grounding path.

Having said that, any reason that say a 2' or 3' section of metal pipe , installed and grounded, right before the dust collector wouldn't relieve the static buildup?

 

[sunnybob]

Not a good idea.
If there is a long run of ungrounded pipe, the static will build up. If you then ground the pipe at the end, thats where there is the greatest possibility of a spark. The last place you want a spark is just before the dust goes inside the collector where you cant see any flame.

My pipe run is only 20 feet long, all in plastic, but I can sometimes feel the static on the hairs of my hand when i hold it close to the pipe. i dont ground anything. even the metal collecting bin is sitting on a rubber pad. No chance of grounding, so no spark.

a factory sized piping system or one that ran for hours at a time would definitely need grounding though.

 

[DaninVan]

I was kind of thinking along those lines, Bob, hence my question. Thanks!

 

[Danman1957]

As far as I know, all plastics are prone to static. Plexiglass is a perfect example. It attracts dust way more than glass. Plastic tubing for central vacuums are all grounded, or should be. Better safe than sorry and it is not expensive to ground your system. I don't have any piping, I just connect to each tool as needed for now. Eventually who knows.

 

[DaninVan]

Oops

As far as I know, all plastics are prone to static. Plexiglass is a perfect example. It attracts dust way more than glass. Plastic tubing for central vacuums are all grounded, or should be. Better safe than sorry and it is not expensive to ground your system. I don't have any piping, I just connect to each tool as needed for now. Eventually who knows.

My Beam's not grounded; didn't even realize it should be!

 

[DesertRatTom]

In my small shop, I have flex tubing, but the runs are never more than 10 feet. Hard pipe would be nice, but the shop is too tightly packed to use it. I probably should cut the length of the hose. Good question Dan.

 

[JFPNCM]

I have about 40' of 4" flex tubing attached to the DC that runs through the rafters with 2 drops with blast gates at the end of the run for the joiner, planer, drum sander, router and ROS as required. A bare 9 gauge copper wire runs through the system to tie it to ground. While there may be some drop in efficiency overall because of the ribbed tubing it handles the DeWalt 735 without issue. Would I prefer to have meal piping, yes, but I can't justify the cost for the change.

Just my 2 cents worth.

 

[DaninVan]

How big (HP)is your DC, Jon? Do you use a pre-container with it (cyclone type lid)?

 

[JFPNCM]

@DaninVan

Dan: It's and old Delta, 50-850 single stage system. The 1 1/2HP motor feeds a short 6" line that goes to the metal pan between the exhaust and collector bags. The specs claim 1250 CFM for the airflow. I haven't added pre-container to the system but one is under consideration. Space is the issue.