Finding Local Ductwork - Not an Easy Task

[Bob Borzelleri]

Sometimes it is pretty darn hard to spend money. Take my current project, for instance. I have the cyclone installed and am chomping at the bit to connect it to the dust makers. Obviously, I need a manner of transport for all that fine dust between the table saw (fill in the blank) and that 7" intake on the cyclone.

Now, having a 7" intake is a mixed blessing. Of course, it provides more "umph" for carrying chips and dust away from my lungs and on to their eventual demise. But, if one wishes to tempt fate and throw minimal caution to the wind by using PVC, the main run is out of luck. Nobody seems to make 7" PVC, ABS or whatever other plastic formulation is typically used for sewer and drain purposes.

Metal spiral pipe comes in 7" diameter, but the last two fabricators I called told me that they do not sell their product for dust collection, "air only; thank you, we are not going to get into the chain of liability for use of our product for dust collection".

"And, do you mind if I ask what sort of product failure you are concerned about", I posed to the fellow on the other end of the line. He told me that his ductwork could collapse if used in a DC system. I followed that with "and what gauge are we talking about?" and he responded 24. At that point, I figured he had already predicted that I really wanted to to do pullups with 100 lb.weights strapped to my ankles and that any further request for clarity was doomed.

On the PVC front, well, there doesn't seem to be 6" ASTM 2729 in California. The irrigation supply houses carry SDR 35 with is twice the wall thickness and weight per foot as ASTM 2729, so instead of wrangling 12 lbs. of 10 ft. section of ASTM 2729 over my head, I would be dealing with 23 lbs. of SDR 35 for the same length. Hmmm...

I know that there are web suppliers of this stuff. It just seems weird that it is not readily available locally (I'm sorta near Sacramento, CA.

...Bob

[Tim Sproul]

Ewing irrigation in San Leandro (bay area) carried ASTM 2729 as of about a year ago.

[Bill Fields]

Hey Bob:

Did you ask Griz or Oneida?

Failing that, I would take a couple of sketches to a local HVAC or roofing contractor who knows how to fabricate duct work and transitions 7" to 4" wye for example.

Failing that, I would call back the folks who turned you down and lie to them.

Do you have a copy of "Woodshop Dust Control"--may be something in there. I believe the more extensive/expensive of the 2 books out on this subject is alleged to have material on industrial strength systems.

Good luck!

BILL FIELDS

[Steve Roxberg]

Try www.spiralmfg.com for your supplies. I have purchased from them and their prices are so good that even with shipping I saved over any available local option. Very high quality parts and very easy to deal with.

They have everything you need.

[Allan Johanson]

I like Bill's idea. Go back and lie to them. They just don't get it. I'm running 7", 28ga spiral pipe and there is no way that stuff will collapse and I'm running a stronger DC than you are. Even my 7", 28ga snaplock from Home Depot is doing just fine.

You're there at the spiral pipe place to pick up pipe for your friend in the HVAC biz. You don't know anything about it except what he wrote down on your list. :D

Cheers,

Allan

[Bob Borzelleri]

Tim...

Thanks for the lead on Ewing. I'll call them tomorrow.

Bill...

Grizzly has some stuff in their catalog that looks like it was fabricated by Michaelangelo. The Oneida pipe looks pretty good, too. Problem is price. I feel like I need to make a run at a less expensive alternative before biting that big a bullet.

I have the 1st edition of "Woodshop Dust Cobtrol". I just have to find it.

Lying is beginning to sound pretty good.

Steve...

I have seen some pretty favorable comments about Spiral Manufacturing. I will call them tomorrow, too.

Allan...

Ditto on the fabrication fabrication.

Thanks guys.

...Bob

[Bill Simmeth]

Ditto what Steve said. Won't be overnight, but Spiral Mfg is the best! ( Not affiliated, yada, yada. )

[Randy Moore]

Bob,

I like Allan's idea the best LIE to them. They don't need to know what you doing. Tell them it is a cash deal and pay in cash. MONEY TALKS and they will sell you what you want.

Keep us posted on your project.

Randy

[Jim Becker]

Bob...it's not for dust collection. It's for moving air at low pressure and high volume. (If it happens to grab a little dust along the way...so be it ;) ) And 24 guage is more than sufficient for your purpose. My metal duct is 26 guage through and through. (Welded laterals from Oneida are obviously much heavier)

Plastic pipe just doesn't come in odd-numbered sizes...anywhere.

[Bob Borzelleri]

Jim...

It looks like I am slowly settling in on spiral pipe. The analogy that is beginning to fit in here is the home storage conundrum. If people took stock of how much of the square footage of their homes is used to store items that are never used and then calculate the cost of that space as a percentage of their mortgage, garage sales would be the next great economic growth opportunity.

The connection is the fact that I have spent well beyond the cost differential between plastic and metal in research at this point and the sunk cost in time, while considerable, isn't enough to keep me holding out for some great deal to come along.

Now that I read what I wrote, maybe the connection is looser than I originally thought, but the end result is the same. Gonna call those Spiral Mfg. folks in the morning.

...Bob

[Bill Fields]

Bob:


Go a chuckle on your theory of the economics of gathering stuff vs. yard sale.

MY DC system is new--sitting in a shiny galvanized trash can alongside my garage. Pipe and tubing and blast gates, couplers, clamps, etc. I'll get to installing it soon.

I see you are/were into bicycles. See my website if you have time: www.billfields.net (http://www.billfields.net). I've been in the bike biz in one form or another for 35 years.

Best

BILL

[mike malone]

BOB
i don't know how close you are to north Los Angeles, but there is a good source there in Sun Valley
hi metal
9313 borden ave
sun valley ca 91352 (linda 818-768-2315)

mike

[Michael Perata]

On the PVC front, well, there doesn't seem to be 6" ASTM 2729 in California.

There are at least three place in San Jose to get 6" S&D pipe. Look in the yellow pages for an irrigation company. ($11 - 13 for a 10' length)

[Kevin Herber]

I suggest going back to the supplier and ordering what you want. If the salesman asks the purpose just say it is for ductwork. If he presses you tell him you have it all designed and you just want the material. End of discussion.

It's hard to imagine a salesman saying he won't sell you something because you won't go into detail on its intended purpose. However, we've all run into that guy who has to display his supposed superior knowledge while making himself look like a moron. If he gives you a problem get another salesman.

Good Luck -- Kevin

[Steven Wilson]

Spiral is nice, so is Nordfab but overkill for a 2hp system. The 7" snap lock from Oneida is fairly cheap , easy to work with, and they'll get it to you in a couple of days. I had initially wanted to go with spiral or Nordfab but was talked out of it because it's really designed for much greater CFM systems than my 2hp Oneida Commercial. The bulk of my runs are snap lock with adjustable elboes (fairly inexpensive). I terminate it all in Nordfab fittings because I wanted to use the Nordfab quick disconnects (a bit pricey) but the bulk of the pipe work was fairly cheap

[Bob Borzelleri]

This forum is an amazing resource. Excellent recommendations, incentive, support and, every so often, a reminder of what is important in life.

Mike...

I'm about 1 light year from Sun Valley, but if unit pricing, taxes and shipping made sense, that might be an option. Thanks for the reference.

Michael...

Looks like I've bitten the bullet and gone over to the shiney side. I called Spiral Mfg. this morning and asked for a quote. Interestingly, their per foot price for 24 ga. 7" pipe is about 1/2 of the cost of SDR 35 ABS. Similarly, the cost of 90 degree elbows is only slightly more than the ABS elbow. The 7X7X6 whyse are about 2X the cost of ABS. The plot thickens.

Kevin...

At this point, if I buy locally, I have decided to script out a scenerio where I am working on a doctorate to research air flow characteristics using hermetically sealed and filtered air under extremely low pressure (with a research protocol that expressly prohibits anyone from doing pullups on the ductwork).

Bill...

What a small world. You founded what was, in my mind, the best alternative to Bicycling Magazine and I was a long time subscriber. I remember when Bicycle Guide came out. My first reaction was to sense an air of independence. I recall thinking that Bicycling had become an "inside baseball" publication in that there were times when I couldn't easily distinguish subjective from objective writing (actually, I could and that was why I had become increasingly dissatisfied with Bicycling). I know that's not a unique criticism coming from a magazine reader within any particular genre, but at the time, I seem to recall that Bicycling had an enormous strangle hold on the market; they had become the poster child for the case for free competition.

I'm sure you are proud of that venture, as well you should be.

...Bob

[Bob Borzelleri]

Looks like I'm back to local shopping. Just received a quote for spiral stuff with fittings and blast gates. I was encouraged by the product cost, but dismayed by the shipping. $325.00 for UPS and $490 for Roadway. I guess its back to the yellow pages.

Steven...

I'll check out the snap lock stuff, too. thanks.

...Bob

[Chris Padilla]

Bob,

How about:

Air-Duct West Inc.
30956 San Clemente St
Hayward, CA 94544
510.487.0200

Yes, shipping KILLS many deals on metal ductwork. I'm still waffling between PVC or metal...I just don't know. I can get the 2729 ASTM S&D 6" here:

Horizon Irrigation (Warehouse or Supplies or something....)
1990 Stone Avenue
San Jose, CA 95125
408.971.9500

Their pipe is reasonable but they don't have many fittings for the 6" stuff. You'll want to get your fittings from McMaster-Carr: http://www.mcmaster.com/

Good Luck...let us know what you end up with.

[walter stellwagen]

You might try www.kencraftcompany.com for 26 gauge fittings.Should be able to buy most 26 gauge at home depot

Walt

[Bob Borzelleri]

Anybody got any thoughts about using 26 ga. pipe and 30 ga. fittings? I ran around a bit today and couldn't find any wyse or elbows stiffer than 30 ga.

...Bob

[Bob Borzelleri]

Walter...

I called KenCraft today. They thought they had some stuff and said they would get back to me. Thanks for the referral.

...Bob

[Jim Becker]

HD and Lowes generally carry 26 guage adjustable elbows...may be labeled as "stove pipe". HVAC suppliers have them, too. The real issue is laterals...HVAC laterals are built "backwards" relative to air flow compared to dust collection.

[Allan Johanson]

What do you mean by being "backwards", Jim? The ones I've seen have the crimped end on the proper side, but have little metal tabs on the inside of the wye. I tapped those down with a hammer and applied foil tape on top of them to make a smoother transition and to make sure no sawdust shavings got caught in there.

HVAC 30ga elbows might work fine considering the seams. Those frequent seams will help strengthen the piece.

Allan

[Jim Becker]

HVAC wyes are designed to push air out and usually have the crimps are on the wrong side for "pull" applications such as DC. The crimp should always be pointing in the same direction as the air flow. Therefore, the lateral wye should only have one crimp...on the side that points towards the DC blower.

[Allan Johanson]

Therefore, the lateral wye should only have one crimp...on the side that points towards the DC blower.
That's exactly how mine are. I guess I lucked out. :D

Cheers,

Allan

[Andy London]

That's exactly how mine are. I guess I lucked out. :D

Cheers,

Allan

Mine were criped on the proper end also however the HVAC store I bought my supplies from also.

Andy

[Allan Johanson]

Mine were criped on the proper end also however the HVAC store I bought my supplies from also.

Andy
Were you still sleeping when you typed that, Andy? :D