Can you guys verify this?

[Adam Cavaliere]

After reading around and trying to wrap my head around all of the Dust Collection info on Bill Pentz website and other threads, I believe I have come to this conclusion:

Dust collection can vary depending on the end result you are looking for. Unless you want to do modification to your tools and also more than likely invest in a cyclone / big motor, you aren't going to get all of the "fine dust".

On the other hand, if you are looking to do full chip collection and some dust collection (ie not the dangerous stuff), you can get by with a 1.5 HP dust collector.

I downloaded Bill Pentz' static pressure calculator and instead of looking to pull 800 CFM @ 4000 FPM, I switched it over to 400 CFM @ 4000 FPM. That reduced the required diameter from 6 inches to a little over 4 inches.

Because of that I am planning on running a 6 inch trunk for my main run and mostly 4 inch runs to the machines. By having the 6 I realize I will be leaving fine dust behind, but I believe anything that isn't exactly "floating" will be grabbed by the dust collector. Can you guys verify that I am correct in that thought?

I figure if my garage door is closed I'll wear a mask while working and also have an air filter running. If the door is open I will have fans circulating air and also have the air filter running.

Let me know what you guys think.

[David Romano]

One of the most important considerations in collecting the fine stuff is how to keep it from escaping the DC system in the first place, i.e., a good hood at the source of dust creation. Without this, the amount of airflow won't make a difference. In the case of a planer, the fines are probably collected pretty well. In a RAS or TS, it is much more difficult. A RO sander is probably the worst. Router DC is too inconvenient in my opinion, each time I use the router the shop is covered in dust. There is no perfect solution. I have a Jet DC 1200 with a Phil Thien baffle and a Wynn cartridge. I think it is darn close to a basic cyclone in performance and less expensive.

Do your best to make effective hoods on your tools, remember to use the DC each time, and wear a mask. I also have an ambient air cleaner that works great when sweeping the floor or doing a lot of sanding

David

[Adam Cavaliere]

David,

Do you feel the ambient air cleaner also helps when using other tools that your DC may not be capturing enough of the dust from?

[David Romano]

David,

Do you feel the ambient air cleaner also helps when using other tools that your DC may not be capturing enough of the dust from?


Adam,
Yes, I like to run my air cleaner whenever possible. It's loud enough to drown out the radio, so if I can put up with the noise, I run it. It keeps the shop from getting a fine layer of dust all over everything. No tool really collects all the dust. The RO sander with a shop vac and a Dust Deputy (mini cyclone) doesn't let too much escape, but I do alot of sanding by hand and unless you've got a downdraft table or a hood placed very close to the board suck mucho CFM, the shop will soon be in a cloud of dust. BTW, get a Dust deputy for your shop vac. My shop vac clogs so quickly with dust and chips, I stopped using it. The DD does a great job separating out the chunks and the fine stuff. It makes the shop vac useful again.

David

[David Giles]

When you run the 6" main, consider installing 6x6x6 tees and swage down to 4" instead of 6x6x4 tees (or wyes). Just in case you change your mind later. It will be much easier to change just the 4" leg to 6" without cutting into the main header.

4" stuff is cheap. You won't lose much money when you upgrade later. :D

I still hold to my basic premise that 4" duct only works with 2-3Hp dust collectors or cyclones. And then it's still just adequate. That's essentially the same answer you get from Pentz' calculators. High air flow isn't possible with 4" ductwork. Will you be satisfied with lower air flow? That's a subjective question. If you have engineering or perfectionist tendencies (and those who wade through Bill's website do), won't be satisfied long term. IMHO. I'm one that is learning to live with "adequate", but I wish that I had done it right the first time.

[Jesse Cloud]

An ambient air cleaner is a great idea no matter how good your dust collection. After I have shut things down, I keep the ambient running for another couple of hours (you can program this automatically) and the air feels crisp and fresh, better than inside the house.

But don't give up on dust control on the router. Lots of folks here trash Festool for being too expensive, but I can route dovetails all day and end up with about 30 seconds of clean up at the end of the day.

Some router or tablesaw situations are just gonna spew, no way around it, but just because something isn't perfect doesn't mean that its without value! I sometimes see woodworkers up to their ankles in dust because they have written off DC since it ain't perfect.:eek::(

[Adam Cavaliere]

That's a subjective question. If you have engineering or perfectionist tendencies (and those who wade through Bill's website do), won't be satisfied long term. IMHO. I'm one that is learning to live with "adequate", but I wish that I had done it right the first time.

David,

Thanks for the response! :)

While I realize this is subjective question, I also feel that all I am looking for is adequate. I don't have a burning desire to suck up every bit of dust to keep me "safe". I just don't want to be dealing with stuck shavings in my jointer and have enough airflow to pull all the shavings off of my planer. The only reason why I hit pentz' site is because he has the most information out there it seems. It is over the top for what I am trying to achieve and I realize that.

I honestly wish there was a site dedicated to the garage weekend warrior type of wood worker who wasn't as worried about his lungs as Pentz is. I do realize the risks, but I am taking a calculated risk and am willing to deal with it in different ways.

In all honesty, I want it so I am not spending 1/3 of my time cleaning up the garage and dealing with a bunch of sawdust all over the place.

Hopefully what I am implementing will take care of that. :rolleyes:

[Rod Sheridan]

Hi Adam, a 4 inch line isn't adequate for many tools.

What are the airflow requirements for your particular pieces of machinery?

Some of my machines have a 5 inch line, my tablesaw has a 4 for the cabinet and a 3 for the overhead guard.

It's best to work backwards from the tool to the dust collector when designing your system.

Many here at SMC have wasted money on less expensive collectors, only to replace them with higher performance cyclone systems.

I've had an Oneida for years, my brother recently installed a 2 HP commercial Oneida in his home shop, and is amazed at how well it works.

Collecting dust at the source is the best way to treat the problem.

A good cyclone with good filters, properly designed ductwork, will work well.

Spend a little more money up front, avoid having to do it all over again.

Regards, Rod.

[David Giles]

From one weekend warrior to another, the planer is probably the easiest to address. Few hobbiest planers have anymore than a 4" connection. And the Dewalt fan assist will blow almost as fast as a choked DC will suck. On the jointer, 4" is probably big enough as well because the chips are relatively big and well contained. But it's real easy to cut a 6" hole in the plastic jointer DC connection and stick in a pipe. All bets are off if your jointer is on a mobile base.

The table saw is where most of the fine shop dust gets thrown around. That spinning blade accelerates the dust particles and it takes a hefty air flow to counteract it. Adding a six inch port to most cabinet saws is easy. Make a template of your PVC pipe and cut to match. Metal pipe has standard takeoffs that can be screwed on.

One of the most my used connections is 25ft of super flexible 4" flex hose connected to a 4" pvc pipe. I can sweep the entire shop floor in 10 minutes! Good luck and let us know how it turns out!

[Adam Cavaliere]

Hi Adam, a 4 inch line isn't adequate for many tools.


I have read Pentz' site and realize why manufacturers put 4 inch ports on consumer products. I have to say though that every tool I have is 4" in diameter.

So I don't want to modify my tools - never had any intention to do so.

That brings me back to my original point about verification. If I am hooking up to a 4" port on my machine, am I going to get the same amount of air flow / suction as I would had I not run the ducting and just hooked straight up to the machine? Because from what I have read, the limit to what a 4" pipe can pull is 350 - 400 CFM. After that you don't get any more... So what is the difference other than a huge amount of convenience from not having to wheel from one machine to another?

[Phil Thien]

Because from what I have read, the limit to what a 4" pipe can pull is 350 - 400 CFM. After that you don't get any more... So what is the difference other than a huge amount of convenience from not having to wheel from one machine to another?

You are correct to a point. Extra ducting will add resistance, and you may drop below 350-400 CFM if your DC can't handle it.

If you can keep the main straight with no twists and turns, you'll do fine. As you add complexity (twists/turns) to your ducting, you'll need a DC with greater static lift.

I've been in shops where the DC is in a corner and there is a single 4" main (maybe 15 to 20' long) down the "tool wall." There are maybe three or four connections for machines (table saw, jointer, planer, table saw) made to this 4" main. I've been impressed with how well it works.

[John Keeton]

I did 6" runs, with vertical drops, and 4" flexduct to each machine. I am sure that I would get better efficiency with 6" the whole way, but I can hog as much wood as my Grizzly 0453 15" planer can stand, and it all gets sucked through the clear flex so fast that I can't even see it. There appears to be no dust escaping - and NO chips. If my Oneida 2.5 did nothing other than that, it was worth the money!

I also like the stationary floor sweep, and I have a section of 2.5 flex that I plug into various open drops (blastgates) I have in my shop for mobile machines and use it as a shop vac. Much easier than fooling with the filter on my shopvac, which I rarely have a need for now.

Aside from the health aspects, I can say that my shop stays so much cleaner. I rarely have a dust layer on anything, and when I do, it comes mostly from hand sanding (going to work on a downdraft table soon), or from my tablesaw and I hope to fix that situation someday soon, as well. I did install 2 separate drops for the TS in preparation for a bladehood at some point. The TS really requires more than a 4" off the port.

I agree with Rod - spend a little more now and do it right. You will be glad you did. My DC system is the best tool I have ever owned. For years, I would "feel" the effects of breathing dust for hours in the shop. No longer! Saves me lots of cleanup time, too.

[David Giles]

Adam, dust collectors move air by "sucking", creating a negative pressure at the blower inlet. A typical suction pressure is 6-8" WG. Take a long straw and pull 8" water into it, put your finger over the end. That's the total driving force to move the air. It's not a lot.

At these pressure drops, air acts like an incompressible fluid in engineering terms. Basically the flow behavior is like water. Consider a 2" water header with 1/2" drops. What sets the total flow? The 1/2" pipe, of course. The is little "flow resistance" in the 2" pipe because of the low velocity. What happens with a 1" pipe? Flow goes up almost proportional to pipe area. How about a 2" pipe? Goes up again, but not strictly proportional because the 2" main header starts restriction flow. How about a 3" drop? Not much increase because the 2" main restricts the flow.

It doesn't take much pressure drop to significantly reduce the flow. The 4" ports act like restriction orifices. No matter how big the main line, 6"WG only pulls so much through a 4" hole. Now if the main line is 4", the flow goes down because there isn't 6"WG at the orifice anymore.

So weekend woodworkers have three choices:
A. Buy a larger blower DC or cyclone that has more suction pressure. The higher suction pressure will pull more air through 4" ports.

B. Buy a standard DC and oversize the ducting including the ports.

C. Use a standard DC with 4" ports and learn contentment with lower air flows. It should be sufficient for the jointer/planer.

But you have to find and buy 6" pipe anyway and hang 6" from the ceiling. Both are time consuming tasks. Why are you spending time reading websites and calculating? It will be faster to just do it!

But to your specific question, a 6" main with 4" drops will have about the same air flow as direct connecting the DC with a 4" flexhose. Basically the 6" line adds reasonably small amount of pressure drop. In reality, the 6" header will pull more because you don't connect to the DC with a 4" line, but with 6". Removing that dual 4" inlet spool really adds air flow!

[Curt Harms]

I think the 6" hose is worthwhile. There has to be some velocity/CFM loss in the air next to the hose, it's like water running over a rapids-it's gonna swirl and slow down. I used 6" PVC and 6" flex to Jointer/Planer and bandsaw. The table saw has a 6" flex to the cabinet. I don't have any overblade dust collection on the TS. This is hooked into a "2 hp" Penn State dust collector w/ wynn filter. Seems to work pretty well.

Curt

[Adam Cavaliere]

Alright! I think I have done enough reading and you guys have verified what I was trying to make sure I understood!

I know you all like pictures, so I'll be sure to do before and after photos to share with you guys :)

Thanks for all the time and responses.

[David Giles]

So have we sufficiently annoyed you into running 6"? :D

[Adam Cavaliere]

I am going to run a 6" trunk and run 4" off the trunk...

[Adam Cavaliere]

You guys had me convinced until I went to Menards and priced out the cost of going 6". Since I am only going to be in my current setting for another 4 - 5 years and it isn't "permanent" in my mind, I decided it wasn't worth the investment to go 6. I am sure I will have a ton of people reading this thinking it was a mistake, but that is OK. I guess I will "live and learn"....

[Phil Thien]

You guys had me convinced until I went to Menards and priced out the cost of going 6". Since I am only going to be in my current setting for another 4 - 5 years and it isn't "perminante" in my mind, I decided it wasn't worth the investment to go 6. I am sure I will have a ton of people reading this thinking it was a mistake, but that is OK. I guess I will "live and learn"....

Lots of people are very happy with their 4" ducting.

[David Giles]

Contentment is a learned attitude that is not necessarily related to dust collector air flow. :)

[Denny Rice]

Adam,

I went to Menards to help my uncle price a PVC dust collection system using 6" PVC, and your right regular schedule 40 6" PVC is very pricey and not needed. You can order 6" S&D PVC pipe for not much more than the 4" stuff, the only problem with Menards is the only way you can get it is to purchase an entire skid (20- 10ft sections) he didn't need that much. Menards does stock 6" S&D fittings Y's, ect.... We ended up finding 6" S&D just this spring at a few differenet places but Carter Lumber was by far the least expensive.

[Jeff Duncan]

I think it's a mistake only b/c your worried about saving a few bucks now b/c you may move in several years? Well when you move just take the duct with you, there's no reason you can't re-use it.
Other than that I think just running 6" all the way to the machines is the way to go. No good reason to step down to 4" at the machine in my mind. Except for machines which require 2 connections, in which case 6" to 2 - 4" ports is just right.
It's your shop though so you do what you need to do;)
good luck,
JeffD

[Robin Cruz]

4" works exceptionally well. for a small shop, 6" is not justified based on impressive performance of smooth bore 4" pipe, the significant added cost for metal or 6" PVC and the room the large diameter takes up.

[Adam Cavaliere]

OK guys,

Everything isn't fully hooked up, but at least I took some pictures and even a small video.

Click this link to go to my site:
http://www.airedalez.net/index.php?option=com_content&view=category&layout=blog&id=37&Itemid=66