Thread: DRAFT Ducting Recommendations

The IPEX Canplas brand of 90s appears to available at several places at a reasonable price.
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I've not used any of these so be sure they're what they look like they are before ordering.

Thanks, Dave. These appear to be constructed along a larger radius than the McMaster-Carr elbows I've been looking at. A hardware retailer chain with a local store seems to carry them and I'll check them out.

Dave, I've found yet another source here in the U.S. for longish turn 6" 90-degree elbows. Similar to what the pictures of the IPEX Canplas suggest, this elbow is built on a larger radius than most other 90s I've seen for SDR 35 and D-2729 (S&D) pipe. It's manufactured by Normandy Products in Pennsylvania and available for online retail purchase in the U.S. from Drainage Solutions.

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Given the longer radius on which this curvature is built, I'm getting more comfortable using it.

For the IBEX Canplus, I was not able to find a specification drawing from which I could get measurements to validate the radius on which that elbow pipe is constructed.

Thank you for allowing me to gain so much good information from forum members here, even though specifics I have shared relate PVC available in the U.S. and not Australia. As we get into making the actual connections to the machines in our community workshop, I will hope to share some experiences more generally relevant to forum members.

As a parting post for now, I thought I'd share where the discoveries about variations in sweep curvatures of PVC 90-degree connectors have led us in our duct layout design. We are using a Clear Vue 5HP CVMAX cyclone in this setup. Green pipes are 8" SDR 35 and blue pipes are 6" D-2729. Comments/questions welcome.

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Design looks fine. I suggest the blast gates be located as close as possible to the relevant trunkline junction. The reason for this is to reduce the possibility of dust building up in less often used ducting lines which end up being under slightly lower pressure due to the Bernoulli and will pull sawdust into themselves over time . When blast gates are located at trunk line level it's harder to use conventional gates so unless you are looking t automated gates maybe look into using Rocker Blast gates. So a search for "blast gate gallery" in this forum and you will see plenty of ideas.

If you decide to make further posts about you own system it would be appropriate to start your own thread on your build as this thread is meant for posts associated with this Ducting Recommendations. If you start a dedicated thread I can move posts dedicate dot your build to that thread.

Originally Posted by BobL

...I suggest the blast gates be located as close as possible to the relevant trunkline junction...

Thanks, BobL. You've certainly hit upon the reason for my hesitation to mount blast gates at the trunk line junction: 8'-9' in the air will require some custom build gates like the rocker blast gates for manual operation. The auto gates would be nice, but I think we're too small a shop to have the expertise among us to take these on as a DIY project. But, excellent observation.

Originally Posted by Rushton

Thanks, BobL. You've certainly hit upon the reason for my hesitation to mount blast gates at the trunk line junction: 8'-9' in the air will require some custom build gates like the rocker blast gates for manual operation. The auto gates would be nice, but I think we're too small a shop to have the expertise among us to take these on as a DIY project. But, excellent observation.

Sorry if you misunderstood. My recommended location for blast gates is not in the trunk but in the 6" ducting just as it leaves the trunk line.

If the trunk line is not too high above the shop floor level then conventional gates can still be used, but if its too high the rocker type gates might need to be used.

The photo below shows the installation of Rocker gates at a local community "Mens Shed" where the trunk line is located about 9ft above teh floor.
The ropes with the green balls attached are pulled open the gates and the red balls are pulled to close them.
Thus looking across the workshop one can quickly see what is opened and what is closed.

ValveHandles.jpg

Very helpful to see this photo. Thank you! I've seen a DIY variant of these gates. I'll have to look into this as an option for our shop.

Originally Posted by Rushton

Very helpful to see this photo. Thank you! I've seen a DIY variant of these gates. I'll have to look into this as an option for our shop.

Also look shere
Blast gate gallery

Just a quick tip on joining 150 flex pipe to 150 stormwater pipe.
If you pull out about 3 or 4 laps of the wire inside the flex pipe with long nose pliers you can then stretch it over the stormwater pipe. Put a hose clamp on that and you have a perfect airtight connection

Thankyou so much Bobl and others for all the info you've put on here over the years. With much research I've gone from having a 2hp 'dust pump' in the shed (thinking I was doing a good job fine dust collection) to now having 3hp cyclone, venting outside with 150 ducting to nearly every machine.

Originally Posted by BobL

3HP and larger DCs can usually utilize 150 mm ducting, while some 4HP DCs can utilise 225 mm ducting, while it normally requires a > 6 HP DC to utilize 300 mm ducting. The final size used sometimes also depends on depends on having the necessary space around machinery and elsewhere in the workshop.

Back to TOC.

Now that 3HP collectors with attached cyclones are more common and commercially available can you recommend 150mm pipes for use with these units? Will they be underpowered and be considered in the same pen as 1 1/2 or 2 HP single stage machines? I am aware the cyclones reduce the CFM over a single stage collector.

I'm looking at the Sherwood 3HP cyclone unit (https://www.timbecon.com.au/sherwood...dust-extractor) for a new setup in a garage with some fixed (TS, Drill Press, SCMS, linisher) and some moveable machines (Planer/Thicknesser, band saw). I was going to run a main line in PVC which can have short runs of flex for most machines with a longer 2m run of flex for the Planer/Thicknesser. This PT has a helical head and mainly chips rather than dusts so less concerned about max CFM for this one machine... Once moved in to new place and up and running DC will be moved to a shed outside and ducting will run into garage to reduce both dust and noise. Max length of trunk line to furthest machine would be approx. 10-12m.

If I'm mad in my thinking please let me know.

Originally Posted by A_J_

Now that 3HP collectors with attached cyclones are more common and commercially available can you recommend 150mm pipes for use with these units? Will they be underpowered and be considered in the same pen as 1 1/2 or 2 HP single stage machines? I am aware the cyclones reduce the CFM over a single stage collector.

I'm looking at the Sherwood 3HP cyclone unit (https://www.timbecon.com.au/sherwood...dust-extractor)...

Until Bob comes along and gives you the good oil...

See if you can get the specs on the impeller size out of them. You can't trust the other figures they give on CFM, etc.

My understanding is that extra HP without an increase in impeller size is just going to cost you more without any benefit.

Likewise, higher CFM and static pressure performance in an extractor isn't going to give better DE if, along with other things, the ducting size is adequate. I went with 6" ducting on my 3HP 3ph 13" impeller + cyclone system.

The manufacturers claim on these units are

At 750CFM (cubic feet per minute) the 2200W (3HP) motor provides exceptional suction whilst being able to be run on a standard 10A house plug. This unit has more than enough power to handle 2 machines at once through its two 100mm intakes or 125mm single intake.

This is the first time I think I have see a DC flow consistent with the diameter of the ducts being use (2 x 4" or 1 x 5" ducts) from any Timbecon DC.
BUT, FWIW, I would hardly call 750 CFM anything to crow about.

To maintain enough air speed the unit you prefer to should probably really be used with 5" ducting otherwise you risk the possibility of sawdust falling out of suspension. Good luck in finding cheap 5" ducting.

If you can located or vent it outside a modified 2HP (modified as per the sticky at the top of this forum) with clean bags and 6" ducting can generate 850 CFM and with clean Pleated filters around 920 CFM would seem a better option, but only for short ducting runs. I doubt it would be any different to the cyclone in your post as its the same size impeller. A standard 3HP twin (again with the same size impeller) but with two filter bags will get you to just over 1000CFM. This is the flow region you need to be operating in according to BP.

My experience with Helical heads is they initially do make a lot of chips but eventually they will also make lots of fine dust. I would avoid a 2m length of flex for a thicknesser as this will really stymie the air flow.

Originally Posted by BobL

DUCTING RECOMMENDATIONS: Construction tips and Ducting Suppliers
...
The cheapest places to purchase are usually dedicated PVC pipe and fittings specialists as they have very high turnover. An example of this in WA are https://www.pipeonline.com.au – they also will ship and although shipping is expensive you may find it's overall cheaper that local hardware or plumbing suppliers. ...

Thanks very much for an informative thread.

I'm having a surprisingly difficult time trying to find a supplier for 150mm PVC stormwater and fittings (45/y tee and 45 bends) in Sydney; any equivalent to pipeonline on the east coast? I haven't tried a shipping estimate for pipeonline, on principle it does seem nuts to think about shipping a commodity like PVC pipe across the country...

Ta,
Ben