LumberJocks

Dust collector trunk line options

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by SweetTea posted 03-02-2018 12:57 PM 1902 views 0 times favorited 13 replies Add to Favorites Watch
View SweetTea's profile

SweetTea

352 posts in 776 days


03-02-2018 12:57 PM

I recently acquired an older two bag Grizzly 3HP dust collector. I am in the process of rearranging my shop layout and getting all of my dust collection lines ran. My question boils down to: can this 3HP Grizzly d/c handle a 36ft, four inch trunk line? It will be the only trunk line on the entire unit, and it will have only one drop which will come down and branch on to 3 shaper tables, but the branch’s will only be around 2ft long as I have my shapers arranges in a circle (back to back sort of) and the drop will come down directly in the middle of this circle. This would allow me to place this d/c in the back of the shop, thus freeing up valuable shop real estate. That will be all this d/c has to do.

My other option is to place the d/c roughly 10ft from the shapers and pipe the line roughly 10ft up to the ceiling then have a 10ft line of 4” PVC along the ceiling and then drop it roughly 6ft down into the center of the circle where the shapers reside. Which stills puts the line at 26ft total, versus 52ft with the other option (well that option would be a 36ft trunk line with a 10ft drop at the beginning and a 6ft drop into the circle). I already have the 4” PVC and really don’t want to go up to 6” unless I absolutely have to. I also already have the 4” flex hose, the 4” blast gates, the PVC to 4” hose adapters, and the 4” three way junction fitting.

Last question, would it be wise to add a trash can separator with either of the above scenarios? Or would that drop the CFM’s a bit too much?


13 replies so far

View BoilerUp21's profile

BoilerUp21

97 posts in 883 days


#1 posted 03-02-2018 01:27 PM

I don’t think you will have too much of a problem. I have a 30’ line with my 2HP Harbor Freight (with dust deputy and Wynn filter) and there is enough suction at the end of the line. I am looking at getting a 3HP though similar to what you have.

View Dustin's profile

Dustin

551 posts in 856 days


#2 posted 03-02-2018 01:37 PM

Man, I know you said you don’t want 6” duct unless you have to, but according to the Pentz static pressure calculator, adding 36ft of 4” ducting adds about 18.7” static pressure (and that’s just the ducting). Conversely, 36ft of 6” only adds 2.4.

If I were in your shoes, I’d try to run 6” from the DC to the ceiling above the tools, then drop down with 4” (or even see about expanding the tool ports to 5”). As for a separator, I hated my cheap trash can separator. I picked up a second hand Super Dust Deputy from another LJ and love it. I’d go for the SDD XL in your case, as it has a 6” inlet and outlet, vs a 5” inlet/6” outlet on the standard SDD.

Bottom line: you picked up a nice and powerful machine, and it’d be a shame to choke down its performance.

-- "Ladies, if your husband says he'll get to it, he'll get to it. No need to remind him about it every 6 months."

View SweetTea's profile

SweetTea

352 posts in 776 days


#3 posted 03-02-2018 01:51 PM



Man, I know you said you don t want 6” duct unless you have to, but according to the Pentz static pressure calculator, adding 36ft of 4” ducting adds about 18.7” static pressure (and that s just the ducting). Conversely, 36ft of 6” only adds 2.4.

If I were in your shoes, I d try to run 6” from the DC to the ceiling above the tools, then drop down with 4” (or even see about expanding the tool ports to 5”). As for a separator, I hated my cheap trash can separator. I picked up a second hand Super Dust Deputy from another LJ and love it. I d go for the SDD XL in your case, as it has a 6” inlet and outlet, vs a 5” inlet/6” outlet on the standard SDD.

Bottom line: you picked up a nice and powerful machine, and it d be a shame to choke down its performance.

- Dustin

If I use a 6” trunk line, and then drop it down to 4” flex hose at the machines, how much performance would drop assuming that my 4” flex hose is less than 3ft long at each machine? Next question, how would I treat the opening going into the d/c? It has three 4” ports on the d/c inlet. How would I go from 4” flex hose coming out of the inlet and into 6” PVC?

View SweetTea's profile

SweetTea

352 posts in 776 days


#4 posted 03-02-2018 01:59 PM

Another option that I have is to remove the filter and collection bags and pipe the dust directly outside of my shop. Would this gain me any real performance over relying on the stock filter and having to empty the bags? I could move the dust collector itself over to the side wall approx 26ft away where there is an opening that I could run a 6” pipe through to the outside of my shop. Then I could remove the three port entrance on the d/c itself and use 6” PVC over to my shapers approx 26ft away.

View Fred Hargis's profile

Fred Hargis

5068 posts in 2609 days


#5 posted 03-02-2018 03:13 PM

Venting outside would actually improve the performance (likely) a good amount. It would also keep you from worrying about clogged bags. It would also (yep, another) make a big mess outside…but that may not be of concern. Usually outside venting is coupled with a separator (typically a cyclone) to just allow the fine dust out. But if the chips aren’t an issue, the only other problem you might face is loss of heated and/or cooled air in the room.

-- Our village hasn't lost it's idiot, he was elected to congress.

View pintodeluxe's profile

pintodeluxe

5739 posts in 2929 days


#6 posted 03-02-2018 04:12 PM

After setting up my hard piped DC system, I learned that 4” pipe is not a trunk line diameter. It certainly would hamper performance over 36 feet.

6” diameter pipe is minimum in this application. Functionally, it’s easiest to match the biggest possible diameter that your powerplant will accept. Some are 6”, while others are 7” or 8”.

3.14 x r squared = surface area of a circle
3.14×2 squared = 12.56 in sq.
3.14×3 squared = 28.26 in sq.

So… what I’m trying to say is 6” pipe has well over twice the cross sectional area of 4” pipe!
Your powerplant has the power for large trunk runs.

The fabric bags will be a limiting factor when dirty. They really choke the system down, and are miserable to clean. That is the main reason I went with a cyclone. If you want to keep this powerplant long-term, you might consider upgrading to pleated filters with paddle cleaners at some point.

Best of luck setting up shop!

-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush

View brtech's profile

brtech

1041 posts in 3039 days


#7 posted 03-02-2018 05:46 PM

I also think you need a 6” main line. I would take off that splitter in the front of the DC. I can’t see what the diameter of the inlet is there, but it could be 6” in which case you should be able to pipe right into it. There are parts around, like for example:
https://www.amazon.com/Goldwood-4330171946-Port-Tube-ID/dp/B000HJ9SAC/ref=sr_1_8?s=electronics&ie=UTF8&qid=1520012326&sr=1-8&keywords=6%22+port
That could be used to make a 6” port on the front of the collector.

Usually, if you have a short length of flex, you are okay. It’s the 8’ or 10’ lengths that drop a heck of a lot of airflow. Remember: no 90s, wide sweep or a pair of 45s with a short straight section.

And sure, exhaust outside if the mess and the make-up air isn’t an issue. Or get good canister filters and replace the bags.

View Loren's profile

Loren

10477 posts in 3764 days


#8 posted 03-02-2018 06:09 PM

Venting outside is the best way to get the
dust out on a budget imo if you can tolerate
the climate control issues it causes.

http://www.woodcentral.com/bparticles/saw_dust_collection.shtml

View fivecodys's profile (online now)

fivecodys

1116 posts in 1752 days


#9 posted 03-02-2018 10:35 PM

I second the Super Dust Deputy and the 6” trunk lines.
If you get the SDD XL it is already set up for 6” lines.
You can vent what ever the SDD doesn’t capture outside if you want and eliminate filters all together.
(if that is an option for you).

That is exactly what I did. http://lumberjocks.com/topics/256729

I work in my very well ventilated garage so replacing the exhausted air is no big deal for me.

My system is much smaller than yours but the theory is exactly the same.
Oneida recommended 5” ducting for my blower and that matched the SDD I bought.
They claim up to 99% of captured dust and chips are captured and only 1% will be sent outdoors.
Since I was using fans and a leaf blower to clean out the shop every night, I’d say that is a major improvement!

Happy Woodworking!

-- There' are two theories to arguin' with a woman. Neither one works.

View 49er's profile

49er

171 posts in 1720 days


#10 posted 03-03-2018 12:55 AM

I have a 5HP Clearvue. I vent to the outside. It is not messy at all. I have two trunk line and ran 6 inch plastic all the way to the machine with very little to no flex line.

-- Correlation is not causation but I did loose my Doctor !!!

View SweetTea's profile

SweetTea

352 posts in 776 days


#11 posted 03-03-2018 10:29 AM

Thanks for all the replies fellas. I have decided to mount my Grizzly 3HP collector on the side wall of my shop and venting it completely outside. I don’t have to worry about the mess, nor will I have any issues with loosing the climate controlled air. I have also decided to go with a 6” trunk line, and will remove the splitter on the inlet of the d/c so that I can run one 6” line straight from the intake. Hopefully this will give me a nice upgrade in performance! I will need a total of four 10ft sections of 6” S&D PVC. I plan to run the 6” PVC all the way to the center of my circle where my shapers reside. I will use no more than 2ft of 4” hose at each machine.

View SweetTea's profile

SweetTea

352 posts in 776 days


#12 posted 03-03-2018 10:42 AM

I have a couple of more issues that I could use some advice on. First, my 6” trunk line will be mounted to the ceiling of my shop. Which has 10ft ceilings. I will take the motor and blower off my d/c and mount it next to the opening in my side wall which is around 2ft from the ceiling. I will have to rig up some sort of solution to hang the motor/blower unit up there, which I am sure that I can figure out. I will see if I can locate some 6” pipe hangers to hold the trunk line up there. Do you guys know where would be the best place to buy two 6” s&d PVC 45’s? I will run the 6” pipe down to the center location where it will be surrounded by my shapers. What would be the best way to go from the 6” s&d PVC to 4” flex hose? The 4” flex hose runs will be extremely short, ie: less than 2ft, and maybe less than 1ft. I picked up a 3 way (4”) junction and 4” blast gates around the holidays.

With that being said, how would be the best way to split the line into three sections for each of my shapers? Should I do this with my existing 3 way junction even though it is 4”? Or should I look around for a 6” three way junction? Last question, should I use my existing 4” blast gates at the machines? Or should I pony up for some bigger blast gates, and if so, how should they be implemented?

View Redoak49's profile

Redoak49

3450 posts in 2105 days


#13 posted 03-03-2018 12:11 PM

I bought my 6” fittings at Menards. I do not see a location in your profile so making a recommendation is not possible.

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com