Duct size for 3 HP DC

[03rangerfx4]

I am a new owner of a used Oneida V system 3hp dust collector.
I have been using a HF dust collector with a Super Dust Deputy, Wynn Filter and 5” snap-lock ducting.
I’m still in the process of getting my shop completely set up the only thing left is the dust collection.
I have most of the 5” collection pipe hung up, but not connected to any of the tools.
My longest run will be 25’ to my table saw. Jointer and planer are about 18’ away from the DC.
Will this 5” piping be adequate for the new 3hp dust collector?
If I was starting out new, I would definitely do 6” pvc, but I already have roughly $400 into 5” piping and Kencraft fittings.
Advice?

[JGrout]

all my main drops are 5" then necked down to 4"

My trunk is 8"

longest run I have is 30'

If you only use one or two gates at a time 5" will be fine.....

[03rangerfx4]

It's just me in the shop, so just 1 gate open at a time.

[fredhargis]

Don't know whether 6" would be worthwhile, but I do know I'd try what I have first. If you need to upsize nothing says it has to be right now. I suspect you'll be just fine, especially if everything goes to 4" at the tools.

[03rangerfx4]

Thanks Guys.
I will try the 5" for now and see how it goes.

[TDKPE]

That would be sensible.

And remember that your new one will have a much stronger blower curve than the HFDC, which has a very anemic curve. So even though your trunk is only 5" dia., more air will move through it, as well as through the 4" branches. You'll probably be leaving a lot of HP on the table as the blower won't work as hard as it can (with just one blast gate open), but that's not going to hurt anything, and you can then explore improvements. If you think it still needs any.

I would also look into adding another branch duct to an overhead blade guard, like the Shark Guard. You've got plenty of blower capacity now, and you can take advantage of that to get the substantial amounts of dust coming off the top of the blade.

[Kudzu]

Airflow or CFM is the deciding factor. You want to keep the speed of air at a certain level to keep the dust suspended. To small and you restrict the volume, too large and you have to low air speed and the dust fall out and lays in the ductwork.