Still Can't Get Decent Chip Collection with the Laguna Jointer/Planer

[Joe A Faulkner]

Using the Pence calculator, I show your Static Pressure loss at 11.07. Not sure what the Fan Curve is for the HF unit. I know several folks have used this design. I've been curious to hear how it is working out for you. You might go to the Thien Seperator forum and see if anyone there has had luck running 6" rigid or you just might try that. Good luck and please keep us posted.

[Alan Lightstone]

Using the Pence calculator, I show your Static Pressure loss at 11.07. Not sure what the Fan Curve is for the HF unit. I know several folks have used this design. I've been curious to hear how it is working out for you. You might go to the Thien Seperator forum and see if anyone there has had luck running 6" rigid or you just might try that. Good luck and please keep us posted.

Actually, I get 8.40 inches using Pentz calculator. That's still huge, but not as jaw dropping as 11.07". How does anyone get a DC to work with that kind of loss? Everyone would need a 5HP unit. That just doesn't jibe with people's real world experiences with far lesser units.

My future plans are for permanent 6 or 7" rigid duct, but I can't install that until I sort out which DC motor I need, and install that first. It's a chicken and egg thing.

Pentz's calculator states that my optimum duct diameter is 7". On a practical basis, I'll likely have to keep it at 6", though I might run 7" mains, reducing them to 6" at whichever machines I can enlarge the outlets to.

[John Lanciani]

Hi Alan,

You might want to invest in one of these, they're $85 from Amazon. The range is .1 to 20" of water, positive or negative pressure. It's a great way to figure out what's going on as you design and build your system, and it will give you real numbers instead of using someones SP calculator that is not particularly accurate for a full system .

I use mine to monitor my filter now that my system is done so it has long term value. I'll let you borrow mine if you're close by.

[Alan Lightstone]

Actually, I have one, John. I just keep forgetting to hook it up when I'm making changes.

How do you use it effectively? Do you make a small hole in the flex tubing and measure the pressure before the machine and check another pressure more proximal in the tubing, or do you just tape the probe in place in the airstream?

[John Lanciani]

What I did was to put a pitot tube that I made up myself from a piece of brake line in my main duct about 2' in front of the cyclone inlet. By measuring from here I can get relative readings that show the effect of changes made up-stream. By taking an initial measurement with just a short piece of duct I was able to see how much SP was added as I built out the system. I could then use those numbers to get airflow readings using Oneida's fan curves.

[Alan Lightstone]

Not sure what my readings mean, or are accurate, but here's what I measured. This is with the Digital Manometer, using it's included tube, placed just before the HF DC inlet.

With just the inlet connected, static pressure was -1.8 in H2O.
With the inlet and the 6" Thien separator connected, the SP was -3.0 in H2O.

With the system hooked up to the Thien, then with about 5' of 6" flex tubing to the converter box on the Laguna, the SP was -3.2 in H2O.

So if I can believe the measurements, the Thien, tubing, and converter box only add 1.4 inches of static pressure. Or as far as fan curves go, I should be getting stellar air flow through the system.

It all seems too low. Even with the cannister filter, shouldn't I be getting higher readings?