PVC or landscape duct for dust collection duct?

[Sean Rainaldi]

I'm setting up a dust collection system for my garage shop and was thinking about using PVC or land scape hose available at the big box stores instead of the flexible hose to save on $. Problem is the OD for PVC for 4" pipe is 4.5" and the ID is 4", whereas the standard ID for the flex hose many folks use for dust collection is around 3 7/8 - for the machine drops such as a tablesaw or a jointer or planer.

Any suggestions how I can adapt to my machiine ports? I could not find anything at either the big box stores or woodworking retailers like a reducer.

Or is there a cheaper alternative to either PVC or the landscape drain ducts at the big box stores?

I think I will be using only the 4" for my floor machines (and 2.5" hose for things like my router table and maybe a sanding table). I'll be tying this all in to my steel city 65110 which has a 4" port - I think it's a 600 cfm unit.

I'll be tying in to my table saw, jointer, planer, router table, chop saw later a sanding table and eventually a band saw and a couple of sanders and will use some blast gates.

Thanks.

[Matt Meiser]

I don't know of any hose or flexible pipe sold at the big box store that is suitable for dust collection. Its not smooth enough inside. Woodwerks (http://www.woodwerks.com/bluetube-c-52_258_857.html)sells a really nice, pretty inexpensive hose that I like.

PVC pipe works great. For 4" pipe to hose connections, I use quick couplers (http://www.woodwerks.com/4quot-plastic-dust-collection-quick-connect-disconnect-p-6868.html). Put a 4" PVC coupler on the end of the pipe then slip the quick coupler inside. Occasionally the fit will be loose and a wrap or two of electrical tape on the quick coupler fixes it.

[Sean Rainaldi]

So just use the PVC over head and the appropriate PVC elbows and fittings (glued with that epoxy) and quick couple with electrical tape and quick couplers to all machines?

Think that would be the cheapest alternative to the standard dust collection hose?

DO they make quick couplers for 2.5" pvc to 2.5" ports?

[Chris Kennedy]

Just to warn you of a potential issue -- I have a 1HP DC about the same size as your Steel City. It chokes on planer chips. You may want to plan on a chip separator on the line to the planer.

Cheers,

Chris

[Sean Rainaldi]

Yeah that is one thing I want to add a seperator.

[Dan Hintz]

I chose to go with sewage PVC pipe... the wall thickness is less than Schedule 40 pipe, which means a smaller OD. If it is still a problem, take a 2" wide ring of it, slice it across the ring to shrink it in diameter a couple tenths of an inch, and glue it inside the main pipe halfway to act as a coupler. I still went with the typical flex hose, though, so removing a bit of the wire and warming to stretch is the way I go.

[Sean Rainaldi]

Do they sell that sewage pipe at HD or Lowes?

Or where could I buy it?

[Dan Hintz]

A buddy found a (semi-)local place that stocked it. Search for piping supply companies in your area... if you're anywhere near a decent-sized city you should find at least one. Wall thickness is about 1/16" for 6", plenty thick enough to handle a few HP of suction capabilities. I think I paid $200 for four 10' straights, ten 45s, one 90, and three Ys.

HD and Lowes only stock Schedule 40 on the shelves, though I never bothered checking if they could order the sewage stuff. I have yet to see 6" of anything in their stores.

[Sean Rainaldi]

Yeah I did not see any there either.

I wonder if Menards carries it.

What is the technical name for it? Just PVC sewer pipe?

...actually I just checked with Menards they call it schedule 30 sewer pipe and sell it for $6.48 for a 10' section 4"dia and have all the y fittings and t's.

[Jamie Buxton]

Use snap-lock metal ducting from the big-box stores for your rigid runs, including bends and junctions. It is inexpensive, readily available, and strong enough. If your machines never move, you can run the snaplock directly to them. If they move, perhaps some flex for the last couple of feet is in order. If you do extensive work on the snaplock, like shortening sections, get the crimping pliers, which'll be stocked somewhere near the snaplock. My shop is plumbed in 6" round snaplock, but I have a bigger DC than you. Perhaps 4" snaplock would be enough for a 600 cfm DC.

[Byron Trantham]

I use PVC sewer pipe and it's associated fittings. A suggestion - do not use 90 dergree fittings. Make a 90 degree by glueing two 45's with about 4" of separation - a nice smooth 90. I don't remember which company, Rockler I think, offers a pvc to standard 4" flex hose fitting now. In fact they offer several combinations makeing the sewer pipe stuff quite easy to set up.

[Matt Meiser]

For 90's you want to use 2 45's to allow for a longer radius. Don't glue! I stick a screw or two in each joint for mechanical strength if needed, then tape with foil tape. Makes future changes much, much easier and you can reuse the parts.

Our Menards pretty much stocks everything in 4" and all the 6" fittings. 6" pipe can be harder to find. I got all mine at Carter Lumber, but not all Carter stores even stock it.

[Sean Rainaldi]

Use snap-lock metal ducting from the big-box stores for your rigid runs, including bends and junctions. It is inexpensive, readily available, and strong enough. If your machines never move, you can run the snaplock directly to them. If they move, perhaps some flex for the last couple of feet is in order. If you do extensive work on the snaplock, like shortening sections, get the crimping pliers, which'll be stocked somewhere near the snaplock. My shop is plumbed in 6" round snaplock, but I have a bigger DC than you. Perhaps 4" snaplock would be enough for a 600 cfm DC.


Is Snaplock cheaper than the schedule 30 sewer pipe?

[Sean Rainaldi]

Ah Matt you live in Ida I am in SE mich area. What's the nearest carters lumber to the down river area?

[Sean Rainaldi]

For strapping what do you guys use to strap the sewer pipe to rafters or ceiling?

[Matt Meiser]

Sean, you are in luck--Carter Lumber in Monroe carries a lot of 4" and 6". Its at the N. Dixie Hwy exit off I-75. Head west toward Monroe, go under the railroad overpass and it will be on your left right after the big curve.

And if they don't have enough of what you need you can jump back on I-75 and head to the Menards in Toledo at Alexis Rd which is also right off 75.

Lowes in Monroe also stocks 4" fittings/pipe and 6" fittings, as does the one in Ann Arbor. The pipe they carry is heavier. Generally Lowes that are closer to rural areas carry the bigger stuff, "city" ones don't in this region.

If you are in the Warren area much, there's a place called Warren Pipe that carries everything.

For all of them, fitting wise, a complete shop DC system will probably exhaust their stock at least once, several times for Lowes. It has to really mess with their inventory :)


For strapping, buy large screw eyes and large zip ties. You can put in the screw eyes and loosely put up the zip ties to hold everything, then snug it up when you are done. Also easy to rearrange later.

[Sean Rainaldi]

By zip ties do you mean those plastic tie wraps?

[Bas Pluim]

Do they sell that sewage pipe at HD or Lowes?
Or where could I buy it?
Try a local landscaping supplier, e.g. John Deere. Some suppliers charge consumers a lot more than contractors, so if you have a friend that owns a business, that could help. Cheapest place I found for fittings online is acehardwareoutlet.com.


For strapping what do you guys use to strap the sewer pipe to rafters or ceiling?
Plastic pipe strapping (comes in metal too, but why make life difficult?) It comes in a big roll, cheap. Lowe's/ Home Depot carries it.
201185

[paul cottingham]

I use thin wall (I think it is S+D) pvc, and join it to flex using the 4" splice sold at Lee Valley. Works great.

[Sean Rainaldi]

Forgot to ask you guys, what should I do for a blast gate?

Could not find anything at Home depot for that...

Any of you improvise and rig up your own gates?

They had some schedule 40 pvc caps there but they are asking about 8 bucks a piece for them...

[paul cottingham]

I use the metal self cleaning ones. fortuitously. they fit in the pvc I use. A little teflon tape, a couple screws, and they stay put well. In fact, I often just clamp them with a screw clamp.

Don't scrimp on this, you'll probably just wind up going to them in the end.

[Sean Rainaldi]

So the only line with suction then should be the one collecting dust at a machine?

Any suggestions how to get the blast gates to fit around 4 1/4 to 4 1/2 OD pipe?

I was thinking about buying that Hancor HDPE triple wall pipe they sell at Home Depot...for sewer and or land scaping i think...and use it with blast gates sold at rockler or woodcraft...

[Matt Meiser]

This is what I mean by zip tie: http://www.amazon.com/Plastic-Cable-Ties-100-Pack-Black/dp/tech-data/B002C0SKBW but all the big box store sell very long ones that work great for hanging duct from screw eyes.

I made my own blast gates. Very easy to do and they work well. I've got two different versions, but any new ones will be like this.

[Sean Rainaldi]

Wow that's pretty cool matt did you seal the joint somehow between the two pieces of plywood that you screwed together?

[BOB OLINGER]

FYI, I got my 4" at Lowes, however, it's not in the same department as schedule 40. Check in the department handling drainage stuff - like sump pump pits, drain tile, etc. for fittings. At mine, the pipe was outside in the garden department.

[Jamie Buxton]

Is Snaplock cheaper than the schedule 30 sewer pipe?

Yes, and it is lighter, so it is easier to install.

[Bruce Wrenn]

For transition from 4" sch 20 PVC to 4" flex, Lowes stocks a fitting that is designed to go between 4" sch 20, and 3" sch 40. 4" flex slides right over 3" end. There is a molded stop inside, which I remove with a long flush trim bit. Tag says" NDS L3P12. UPC # 52063 33712 8. For blast gates, some brands of sch 20 are a little thicker wall, and will fit snuggly over 4" aluminum blast gates. I have a length, and use short pieces of it as a "bushing" in fittings at blast gates.

[Sean Rainaldi]

Thanks bruce,

Is the stuff you use similar to that Hancor HDPE triple wall pipe they sell at home depot in their garden section?

that stuff goes for about 75 cents a foot. The Snaplock stuff seems more expensive.

[Sean Rainaldi]

thanks Jamie,

Is Snaplock the stuff sold in heating section for heat ducts?

Both Lowes and HD carry it?

[Jim Matthews]

The drain pipe idea is impractical, as the material is difficult to terminate and rather inflexible.

I hear no mention of spark suppression and grounding in this discussion. Sawdust explosions can take out a garage wall.

Dust goes BOOM (http://www.wonderhowto.com/news/wonderment/boom-sawdust-explosion-tested-by-mythbusters-0113376/)!

[Matt Meiser]

Sean, for the latest ones, I just used prefinished maple plywood scraps for the outer parts. I used a beam-type circle cutter to cut a hole for the pipe, then mechanically fastened the pipe from the inside with small screws and caulked. The core is 1/4" material. I cut a U-shaped slot so there are no tricky corners to clean and sandwiched the outer part of the U between the two ends. In practice I've never had any issues with them trying to clog up.

As for static causing explosions, its been debated 1000's of times on the forums. No one has ever cited a real case in a small shop. If you light off road flares in your PVC ductwork, maybe--if you get the right fuel to air ratio, which is unlikely. Grounding PVC is like herding cats--you can try but you won't succeed. Its a non-conductive material.

[Sean Rainaldi]

The drain pipe idea is impractical, as the material is difficult to terminate and rather inflexible.

I hear no mention of spark suppression and grounding in this discussion. Sawdust explosions can take out a garage wall.

Dust goes BOOM (http://www.wonderhowto.com/news/wonderment/boom-sawdust-explosion-tested-by-mythbusters-0113376/)!

Yeah I was going to ask about that - should I ground the duct work with copper wire attached from the duct to a copper pipe hammered into the ground outside the garage?

[Sean Rainaldi]

As for static causing explosions, its been debated 1000's of times on the forums. No one has ever cited a real case in a small shop. If you light off road flares in your PVC ductwork, maybe--if you get the right fuel to air ratio, which is unlikely. Grounding PVC is like herding cats--you can try but you won't succeed. Its a non-conductive material.

thanks for the info on your blast gates Matt.

As for grounding, would it be safer then to use metal duct and ground it, instead of PVC?

I have a friend who told me about the dangers, and I often get static electricity shocks from the colllector - can't remember if it was from touching the flexible tubing or what...

[paul cottingham]

Scan through some of the other post on this forum about static explosions, I think this has been pretty much debunked, even the mythbusters couldn't get dust to explode that way. I believe the massive explosions on mythbusters were all set off by flares. Metal is easier to ground, but more costly.

[Sean Rainaldi]

Sean, for the latest ones, I just used prefinished maple plywood scraps for the outer parts. I used a beam-type circle cutter to cut a hole for the pipe, then mechanically fastened the pipe from the inside with small screws and caulked. The core is 1/4" material. I cut a U-shaped slot so there are no tricky corners to clean and sandwiched the outer part of the U between the two ends. In practice I've never had any issues with them trying to clog up.

As for static causing explosions, its been debated 1000's of times on the forums. No one has ever cited a real case in a small shop. If you light off road flares in your PVC ductwork, maybe--if you get the right fuel to air ratio, which is unlikely. Grounding PVC is like herding cats--you can try but you won't succeed. Its a non-conductive material.

Matt,

What size collector do you use?

[George Clark]

The drain pipe idea is impractical, as the material is difficult to terminate and rather inflexible.

I hear no mention of spark suppression and grounding in this discussion. Sawdust explosions can take out a garage wall.

Dust goes BOOM (http://www.wonderhowto.com/news/wonderment/boom-sawdust-explosion-tested-by-mythbusters-0113376/)!

Jim,

Unless you can point to a documented case of this happening in a home shop, I believe you are perpetuating a myth. The theory may sound good but reality just doesn't back it up. There are literally thousands of home shops with PVC for ductwork and no documented dust explosions caused by static discharge according to many many on line discussions. Unless you have some documented data, we probably ought to leave this dead horse alone.

George

[Dan Hintz]

To back George's statement up, there was a test I mentioned a number of months back about this very thing... can't recall exact numbers offhand, but it amounted to dust particles of a certain size (a relatively fine grit sandpaper) being created at a rate so high it would take a 36" wide belt sander removing 1/4" of wood per minute in an airstream moving fast enough to keep the airstream saturated with the dust, and so on and so on... followed by a spark. The numbers they were talking about were way higher than any Joe Schmoe could do in a home shop... it was approaching industrial setups before it was a potential problem. With the equipment any of us have (or ever hope to have), it simply wasn't possible to reach that correct dust-to-air ratio for an explosion to happen.

Explosions are something to worry about... just not by us.

[paul cottingham]

Bear in mind, tho' that pvc can give you a good zap when sawdust is running through it. My planer "generates" enough static electricity to raise the hairs on my arm, and give me a good crack if I'm not careful.

Do I worry about an explosion? Not at all. Besides, no-one has been able to explain to me how to ground an insulator.

I get pretty good dust extraction with 4 in. pipe and a 1.5 HP collector. But I really want a cyclone, and want to use it with 6 in. duct. (PVC if it's cheaper.....)

[Matt Meiser]

Sean, I have the Grizzly 3HP cyclone.

[Sean Rainaldi]

I only have a one horse 700 CFM with no cyclone so I think it would be better to use it at the machine for now.

[Alan Schaffter]

So just use the PVC over head and the appropriate PVC elbows and fittings (glued with that epoxy) and quick couple with electrical tape and quick couplers to all machines?

Think that would be the cheapest alternative to the standard dust collection hose?

DO they make quick couplers for 2.5" pvc to 2.5" ports?

DO NOT USE EPOXY or GLUE!!!! Friction fit is fine add a little screw if needed on vertical runs, and seal with a small bead of pure silicone caulk (not latex) applied to the outside of each joint after assembly. If you don't it will be a pain to reconfigure if needed- and it is always needed!

[paul cottingham]

DO NOT USE EPOXY or GLUE!!!! Friction fit is fine add a little screw if needed on vertical runs, and seal with a small bead of pure silicone caulk (not latex) applied to the outside of each joint after assembly. If you don't it will be a pain to reconfigure if needed- and it is always needed!
I just used tape and screws. Works great.