Dust collector pipe sizing

[cody michael]

I have a grizzly 2hp dust collector, it has a 5 inch port for the impeller. Can I run 6in main lines off of it without issue? They would be short, 10-15 feet, metal tubing. I have some 6 in already, 5in I would need to buy and someday I would like to upgrade it.

Mainly I use it for planer, jointer, and tablesaw.

[Jim Becker]

You can by using a reducer. It's not optimal performance, but it will work.

[cody michael]

You can by using a reducer. It's not optimal performance, but it will work.

Is it worth spending the money to buy 5in if I already have 6in?

[jack duren]

I think I’d really consider the 5”. I run 5”, down to 4” at the machines. You run a 6” off the DC and You may only be able to properly DC one tool at a time. I can easily do two with the 5” reduced to 4” at the machine..

[George Yetka]

I agree with Jack I think the 6" will function fine and I would not use more than 1 port at a time. Though this is really all the system could run to begin with.

[Jim Becker]

Is it worth spending the money to buy 5in if I already have 6in?

Since you indicate that you intend to upgrade in the future, replacement of the 6" with 5" would not make financial sense to me if the future isn't "way in the future". The DC you have now is potentially marginal for great performance, so I'd leave the 6" you have in place and save your shekels for a DC upgrade to something that can move a lot more air...that's the secret sauce for good dust collection: being able to move a lot of air at high velocity and low static pressure because that's what moves the dust and chips. It's not about "suction" like with a vacuum cleaner/shop vac. My current system is a Harvey G700 with a 6" main up into the rafters which then transitions to 5" for most of the entire network since most of my tools have 120mm ports which is about 5".

[cody michael]

Its only ever me in the shop so one tool is fine. I was going to run a wye off the dust collector one branch would be for tablesaw the other branch for planer/jointer. I would put gates next to the wye.

[Paul F Franklin]

Really the only downside to running 6" instead of 5" is that the air velocity will be lower in the 6" pipe. But the velocity will go back up when you reduce down to 4" for the machines. In theory this can result in chips settling out of the air in the 6" sections because the air isn't moving fast enough to keep them moving. As a practical matter, you are unlikely to see this to any worrisome extent. I'd go with the 6"

[Bill Dufour]

My theory is 6" is fine for horizontal runs. If it is too big the extra will just fill with sawdust and make it 5" equivalent. Only an issue in uphill runs.
6" is much easier and cheaper to find in PVC for my location. I can find a little 5" pipe but no fittings local.
Bill D

[Aaron Inami]

Which Grizzly 2HP dust collector do you have? I'm not aware of any normal dust collector that has a 5" inlet. They normally have a 2x4" splitter mounted directly on a 6" inlet. Even the smaller 1-1/2HP dust collectors use this standard. The only 5" inlet I have seen is on a Oneida Dust Deputy cyclone.

[cody michael]

Which Grizzly 2HP dust collector do you have? I'm not aware of any normal dust collector that has a 5" inlet. They normally have a 2x4" splitter mounted directly on a 6" inlet. Even the smaller 1-1/2HP dust collectors use this standard. The only 5" inlet I have seen is on a Oneida Dust Deputy cyclone.

Mine is older, it has a 2x4 splitter to a 5in port.

[David M Peters]

I have the 2HP Jet cyclone whose inlet is about 5-3/4. I use 6" DWV PVC all over the shop without issue. Longest run is a good 30'.

[Ron Selzer]

Which Grizzly 2HP dust collector do you have? I'm not aware of any normal dust collector that has a 5" inlet. They normally have a 2x4" splitter mounted directly on a 6" inlet. Even the smaller 1-1/2HP dust collectors use this standard. The only 5" inlet I have seen is on a Oneida Dust Deputy cyclone.

I have 2 Grizzly 2hp dust collectors, one bought in 1988 new and one bought used. Both are 5" inlets
Ron

[Curt Harms]

Really the only downside to running 6" instead of 5" is that the air velocity will be lower in the 6" pipe. But the velocity will go back up when you reduce down to 4" for the machines. In theory this can result in chips settling out of the air in the 6" sections because the air isn't moving fast enough to keep them moving. As a practical matter, you are unlikely to see this to any worrisome extent. I'd go with the 6"

Me too. I have a "2 h.p." Penn State dust collector with 12" impeller. Ducting is 6" S & D PVC. The only time I've been aware of chips settling out is when I was using 2 1/2" hose on a router table fence and didn't open another blast gate. When I used a different machine with larger ports I heard a slug of chips from in the line that had settled out when the 2 1/2" hose was in use. Opening another blast gate a little to admit more air fixed that problem.

[Michael Schuch]

I have a grizzly 2hp dust collector, it has a 5 inch port for the impeller. Can I run 6in main lines off of it without issue? They would be short, 10-15 feet, metal tubing. I have some 6 in already, 5in I would need to buy and someday I would like to upgrade it.

Mainly I use it for planer, jointer, and tablesaw.

I use 6" duct on my Jet 2hp dust collector with a 5" port (it came with a 5" to dual 4" Y fitting) and it works just fine. Some day you might upgrade your dust collector and you will be happy you invested in 6" instead of buying 5".