Hard Ducting For The HF 2HP DC

[Tom Miller]

My biggest gripe with the setup is getting to the blast gates which, unlike a lot of what I've read, I have kept right at the the wye to the main trunk line so that there is less static load on the runs to the machines.

Yes, I've always heard you should keep gates nearest the main, for the reason you state. Sadly, I don't always do as I'm told. But I think my branch lines are pretty short that it shouldn't matter much.

Regards,
Tom

[Tom Miller]

I think what Pentz is saying there...

I think his main point, though, is that you have to have 6" dust ports (or equivalent) on your machines to do a good job of getting everything; because that's really the only way you can get the 800 cfm at the machine, which, again is what you need, according to Bill.

I believe he has re-engineered his machines to accomplish this, hasn't he? I'd check his site to corroborate this, but it always makes me soooo sleepy....

Regards,
Tom

[ironhat]

Per your last statement, Jeff, this stuff makes me nuts!!! It's like getting a second and third opinion from docs until you're told what you want to hear.

That aside, have opted for keeping my piping just off the floor, at the same level as the DC machine's inlet. My thinking was to reduce the effects of gravity and best use the available cfm of the HF unit. Granted, when I want to hook up to the TS it means a hose on the floor. Most everything else is along the wall so the hose hazard is a non-issue there. My biggest gripe with the setup is getting to the blast gates which, unlike a lot of what I've read, I have kept right at the the wye to the main trunk line so that there is less static load on the runs to the machines. I have opted to use a 3/4 x 3/4 piece of hickory (or whatever) to manage them. The engeneering boggles the mind - LOL.
FWIW,
Chiz

[LarryG]

I think what Pentz is saying there -- at least, this is how I've always interpreted it -- is that a commercial operation might have a main trunk that's truly massive, with a correspondingly large cyclone*** driving it, with reductions as required ... maybe to eight inches, maybe to six inches, but probably no smaller than that. For a small hobbyist shop, the floor plan dimensions and longest runs are small and short enough that 6" will suffice for everything.

(***There's a furniture manufacturing outfit in the industrial park here that has a cyclone that must stand thirty feet tall, with an intake that's about that many inches in diameter.)

[Jeffrey Schronce]

I have always avoided Bill Pentz site due to the controversy and it's relatively unorganized structure. I started taking a look at it today and found this nugget :

"Unlike big industrial sites, most hobbyists should run the same sized ducting, fittings and hose right up to their machines. Don't do like many and run a 6" trunk line then come off with smaller duct or flex hose."

Huh? That is the exact opposite of what I have heard.

[Jeffrey Schronce]

We have the D2729 stuff here. S&D. It's not the schedule 40 stuff. Bill Pentz' site mentioned it and said what it was made of -- styrene also ? It's white but it's thinner walled than the schedule 40. There are a good many connection pieces as well but I could only find 45's, not 22.5's.

I wonder if that thinner walled stuff would collapse in with the higher end DC units -- like a 3-5 HP cyclone.

How hard is it to find 5" or 6" in this type of pipe ? Obviously can't just pick it up at HD or Lowes.

Steve

My local HD/Lowes has white S&D and Green S&D.
The green is the stuff that fit the DC fittins real well in my experience.

The thin walled S&D is fine for cyclone.

6" S&D is easy to find. However, costs for 6" S&D approach that of entry level metal so you have to compare costs/benefits.

[ssmith1627]

We have the D2729 stuff here. S&D. It's not the schedule 40 stuff. Bill Pentz' site mentioned it and said what it was made of -- styrene also ? It's white but it's thinner walled than the schedule 40. There are a good many connection pieces as well but I could only find 45's, not 22.5's.

I wonder if that thinner walled stuff would collapse in with the higher end DC units -- like a 3-5 HP cyclone.

How hard is it to find 5" or 6" in this type of pipe ? Obviously can't just pick it up at HD or Lowes.

Steve

[Jeffrey Schronce]

Tom is right on here. Schedule 35 is much more adaptive than the white stuff. Fits real well over blast gates, both plastic and metal.

[Tom Miller]

Tom (and others): I know that you used the green S&D pipe, but ... tell me again, please, what kind of gyrations you had to go through to mate these up with standard 4" DC hose and fittings? Am I right in remembering that this pipe uses the standard white Schedule 40 fittings?

Lastly, the Lowe's here has the green S&D pipe, Schedule 35, for around $15 for a 10' piece. They also have a white pipe that has a bell on one end; it too says S&D but it's not Sch 35. It appears to be exactly the same stuff as the perforated pipe used for foundation drains and leach lines, sans the holes. Cost is seven bucks per 10' stick. Has anyone used this? If so, does it use the standard Schedule 40 fittings?

Schedule 40 fittings do NOT fit the green (schedule 35) S&D pipe. At my HD, the S&D fittings, which may be made of styrene, are in a smaller section next - to the Schedule 40 fittings. Also, the schedule 35 pipe I get at HD has one flared end, to allow connecting pipe end to end, FWIW.

I'm not sure how well the thinner wall white stuff fits these fittings, or how it will work with the stock dust chutes on machines. So you'll have to do your own research if you go that route.

One more note about nomenclature: the schedule 35 stuff is also referred to as ASTM 3035, and the thinner white stuff is ASTM 2729. You may see these markings on this pipe.

I find the schedule 35 pipe fits OVER the following:
- aluminum blast gates (use a screw or two if you need rigidity)
- most 4" plastic machine dust ports (Jet jointer, Ridgid planer, Performax drum sander)
- most plastic (Jet brand, e.g.) DC fittings, INCLUDING 4" to 2.5" REDUCERS. While it also fits over the elbows, wyes, etc., I recommend against these in favor of the styrene fittings for better air flow.

The schedule 35 pipe will fit INSIDE:
- the styrene fittings made for it. D'uh!
- the clear DC flex hose that you get at Rockler or Woodcraft, but you first need to remove a couple turns of the reinforcing wire. I usually use a hose clamp, too. With a 4"-6" piece of pipe inside the end of such hose, it is now a quick-connect fitting for a 4" DC port on a tool.

Here's a pic that shows some of this:



Regards,
Tom

[LarryG]

Dave and Steve, this excerpt from Bill Pentz's web site covers that very topic:

"My respiratory doctor recommends installing a good quality ceiling mount air cleaner to help keep the shop air cleaner. He said the ceiling units are worthless for protection while you work, but they do help to clean up the air so every time you go back, you don't start with the same problems. I asked which one and he said that the magazines rated Jet, Delta, JDS, and Penn State all pretty close, but he bought a Jet for himself because he likes Jet tools. In looking at many woodworker posts and some magazine reviews, it appears that he did pick one of the best.

"In following up I decided that if I caught the dust at its source and just let my cyclone run, an air cleaner would not be needed. An air engineer friend said that AAF had done extensive testing and found that was not accurate. An air cleaner is setup to stir the whole volume of air in a room. Without that stirring, much of the fine dust will be missed. Unless you setup your cyclone system so the air coming out of the filters blows in a directed stream at close to ceiling height, what happens is the air creates a narrow racetrack between whatever gate is open and the cyclone filters without doing a good job of cleaning the rest of the air. Moreover, a good air cleaner uses a small motor, meaning my dust collector would use more power and cost far more to run, plus is noisy."

Don't forget too that the CFM ratings of virtually all DCs are shamefully exaggerated. IIRC Wynn's testings found the 2HP HF unit that many of us own, and which is rated at 1600 CFM, actually moves more like ~550 CFM.

Also, I read somewhere -- although I've not been able to find it again -- that even the air cleaners with their larger intake areas will not scour all the air in a shop ... a given filter may move (say) 1000 CFM but it will do this by repeatedly recycling easily-moved air within the immediate vicinity while the air in the far corners of the shop, or blocked by tools or fixtures, will remain undisturbed and will never get filtered. This seems somewhat at odds with what Pentz says above (which is why I wish I could find wherever I read this again).

[ssmith1627]

"Why not just leave the DC running for a while after you're done cutting? The DC should "turn around" all the air in the garage fairly fast and filter out the fine dust that's hanging around (assuming you have a low micron bag or cannister on the DC)? That fine dust doesn't settle fast and at 1600 cfm a DC should "turn around" the air in a two car garage in under 5 minutes. "

Interesting idea. Maybe with ALL the blast gates open ? Would be acting as an air filter at that point. I don't know how effective it would be.

Steve

[IBBugsy]

"But if you're getting that fine dust settling all over the shop it means it's in the air and that you don't have the airflow at the tools to capture it there. At least that's my understanding. And if that's the case, it's loose floating in the room and you're breathing that same air."

To add more thought to this thread......

Why not just leave the DC running for a while after you're done cutting? The DC should "turn around" all the air in the garage fairly fast and filter out the fine dust that's hanging around (assuming you have a low micron bag or cannister on the DC)? That fine dust doesn't settle fast and at 1600 cfm a DC should "turn around" the air in a two car garage in under 5 minutes.

I don't do a lot of cutting so I can't vouch for this but it just seems logical to me??

[LarryG]

Thanks to everyone for the replies thus far. It sounds like I won't at all be overtaxing my DC with the "plumbing" I will need. In fact, I've realized that the lengths of runs reported here will actually free me up to arrange my tools a little differently than I've been planning to do, just by adding a couple more runs of inexpensive pipe.

Loring: yes, I'm planning to use long-sweep fittings wherever I can, whether factory-made or cobbled together out of two 45s and a short length of connector pipe.

JR: I agree about the need for an air filter. It's one of the things I intend to get when I move into the larger building, as soon as I can work it into the budget.

Tom (and others): I know that you used the green S&D pipe, but ... tell me again, please, what kind of gyrations you had to go through to mate these up with standard 4" DC hose and fittings? Am I right in remembering that this pipe uses the standard white Schedule 40 fittings?

Lastly, the Lowe's here has the green S&D pipe, Schedule 35, for around $15 for a 10' piece. They also have a white pipe that has a bell on one end; it too says S&D but it's not Sch 35. It appears to be exactly the same stuff as the perforated pipe used for foundation drains and leach lines, sans the holes. Cost is seven bucks per 10' stick. Has anyone used this? If so, does it use the standard Schedule 40 fittings?

[ssmith1627]

"It pulls everything just fine, although, for a variety of reasons, I get some dust in the garage and need to shopvac the shop after working."

JR -- I guess that's the scary part to me. Maybe Bill's site just really has me worried. But if you're getting that fine dust settling all over the shop it means it's in the air and that you don't have the airflow at the tools to capture it there. At least that's my understanding. And if that's the case, it's loose floating in the room and you're breathing that same air.

I just wonder how much large ducting will really help with our tools like the BT. It seems crazy to run 6" PVC up to the back of the BT and then narrow it down to 2.5".

It sure makes you look at tools in a new way when you think about buying. It's not just how the tool does the job it's how it allows for dust collection at the same time. It's certainly a lot more important than I knew in the beginning.

Not trying to be an alarmist.....just want to be safe in this because I'm 38 now and I hope this can be a long term hobby for me.

Steve

[JR]

I'm running my HF DC about 15' plus up and down. My planer and jointer are at the end of the longest run.

It pulls everything just fine, although, for a variety of reasons, I get some dust in the garage and need to shopvac the shop after working. I don't get any clogs.

IOW - you're just fine planning for the HF DC to pull that distance. I use long radius 90's and wyes when I can. I run as much hard pipe as I can. I put the blast gates as near the tools as I can.

I plan to install an air filter at some point and believe everyone should have that in his plan. You can not get everything with the DC. You just can't.

JR