Do you think the baffle takes away much power?
If so, then, yes, the extra stage you are adding inline with any pre-filter design will be robbing the system of power as it adds additional resistance and turbulence to the airflow (as well as the additional duct/hose length associated with inserting it inline), which does rob one of both static pressure and air volume versus no added pre-filter inline. . . . .
To clarify, my DC is 2 HP. That being said, does it make sense for me to finish making the thien baffle? The machines I plan to run duct work are: miter saw, table saw, planer and router table. Maybe in the future I will have more machine but doubt at this point due to the size of the space I have.
Sounds like my best option at this point is 4" PVC. I'm drawing out now how I think I can make this work and I am sure I will have questions to post along the way. Thanks for the help everyone!
Ideally you would plumb with 6" PVC pipe (which may require enlarging the inlet opening on the DC if the main inlet is not already 6"), then drop down to 4" flexible hose or PVC (whichever is most practical) for the shortest practical distance at each tool. You can also opt to go 6" all the way to each tool, but that usually requires enlarging the opening on each tool. Look for broad sweeping right angle fittings (such as used in waste lines), or make the turn in two steps using 45-degree fittings, rather than the abrupt right angle fittings typical of plumbing for water to help reduce turbulence at each turn. When you need to branch off a main line use Wye fittings and not Tee fittings, ensuring that the orientation of the Wye flows in the direction of your DC (if you get it turned around it will be oriented upstream instead of downstream towards the DC).
Thanks for this. I've read in numerous places that installing larger main lines than your DC inlet does not increase efficiency and is not the way to. Now, that being said, if your DC has a 4" inlet (as mine does) but enough power to move the air in 6" lines (does mine being a true 1.5 HP), is that the way to go? Of course $$ is always an issue but this is something that I see being used for a very long time, so if I should run 6" main lines, that is what I will do.
Now I have made a dust "hood" for my miter saw, so running 4" is fine to that, but the planer outlet is not 4". How does one handle this? Same with the router table and actually the table saw. I have seen some mods out there to make for better collection on these 3 machines I mention...A dust hood for the table saw, and some other creative ways to help capture dust (https://www.pinterest.com/pin/470344754807520195/ ; https://www.ridgidforum.com/forum/p...rum/36538-shop-built-table-saw-upgrade-ts3650). So I guess I bring in a whole new topic...how to reduce your runs to each machine??
Direct answer: You don't need it to do that. I did, however, ground the blast gates to each machine.So, let me back up and ask specific questions;
1. Is it recommended to have sewer grade PVC or metal piping? Why?
1a. If you say PVC, I've seen video of grounding a copper wire and wrapping around the pipe. Needed, or waste of time?
Yes. I have 6" mains and drops then reduce to 4" w/ 4" blast gates, then 4" flex to machines. Keep the flex as short as possible and buy the best quality you can with a smooth inside surface. BTW contrary to what a lot of guys say 4" pipe is NOT adequate. 6" is pretty much a minimum size for any collector in the 1 1/2 - 2HP range. 3HP and up you are looking at 7-8" pipe.2. Size of pipe? Do I run 6" as the main pipe and have reducers to each machine?
They say the further up the trunk at possible but I don't think there's an appreciable performance difference. I prefer to have the gates close to the machine for easy reach.3. Blast gates....matter where they are installed?
IMO you can buy them too cheap to warrant building them. Plastic gates are too cheap. I got the metal gates PennState Industries. Got my flex there too.3a. Metal, plastic or spend the time making your own?
Yes. I have 6" mains and drops then reduce to 4" w/ 4" blast gates, then 4" flex to machines. Keep the flex as short as possible and buy the best quality you can with a smooth inside surface. BTW contrary to what a lot of guys say 4" pipe is NOT adequate.
6" is pretty much a minimum size for any collector in the 1 1/2 - 2HP range. 3HP and up you are looking at 7-8" pipe.
They say the further up the trunk as possible but I don't think there's an appreciable performance difference. I prefer to have the gates close to the machine for easy reach.
If you can vent your collector outside, eliminating the filter will increase performance. However, in a small shop replacement air and heating can be an issue.
If you go with PVC be aware the money is in the fittings. I found there are cheap ones and expensive ones. For example, don't get a sweep T get a Y fitting. For a 90 degree turn, don't use 1 - 1/4 bend (90) use 2 - 1/8 bends (45's) with a short run between.
Do not glue the fittings. I rivetted mine and wrapped with duct tape.
Because DC connections to ww'ing machines are usually 4". For a lot of machines fabricating a DC shroud to fit 6" is neither practical or necessary because reducing the last 3-4 feet does not affect performance enough to matter.I have problems with some of your statements:
You are rigtht, 4" is not adequate, so why did you reduce! The only reason to ever reduce is if you have and under-powered DC and plan to have more than one gate open at a time.
I don't have performance curves (nor do I undertand them) but I will say from my research almost any DC 100CFM and up will perform better with 6" ducts. In my case its a 1 1/2HP Jet DC. I haven't measured the actual CFM at the machine, but in real life it pulls very well from my table saw which is 25 feet from the DC -- and that's with a cyclone. Before I remodelled my shop I had (incorrectly) piped with 4" ducts all I can tell you is the difference before/after was remarkable.Actually the typical 1-1/2 to 2 hp DC can't move enough CFM through a 6" duct, no less a 4" line, especially it has a small diam. impeller (10" - 11").
Bill Pentz's website and talking to DC engineers at Oneida and Penn State Industries.Who is "They?"
Isn't that what I said? But in actuality, if you read what the experts say, it actually does make a difference, but to me not a practical one.In almost every case it just doesn't matter where you locate a blast gate- at the end middle or start of a drop. Air will not flow anywhere in the duct if there is a closed gate blast gate, regardless of the location of the gate, so there is no impact on SP or DC performance elsewhere in the system. Locate gates where they are easy to reach.
If you check you will see I was referring to exhausting outside.This is not as a much a consideration as many think. The amount of air lost has minimal thermal mass compared to the shop structure and its contents which have over 100 times more thermal mass and will warm the new shop air quickly. It only becomes an issue if you discharge outside and run the DC continuously for extended periods.
I assumed everyone knew I was talking about S&D pipe.The difference is in the type of pipe and matching fittings. You must get the correct PVC - "thin-walled" S&D (ASTM 2729) (or the thicker-walled, but heavier SDR35 (the blue/gree stuff which has the same O.D. as ASTM 2729) is the correct stuff to get instead of Sched 40 (standard residential plumbing grade). A 6" X 6" X 6" ASTM 2729 PVC wye (usually marked ASTM 3034, 3035) will typically run $16 to slightly over $20 while Sched 40 (and most good metal) wyes of the same size can run $35, $40 on up!
Yes screws are better I've done it both ways. Guess the point is don't glue it. I've tried using caulk and had it fail. This is why tape is recommended. HVAC tape is fine but I've always used duct tape. Used it on 3 different DC systems and never seen it deteriorate as you describe (one system was >10 years) even if it did, so what?Rivets are a pain to remove same as duct tape- very few people ever install a DC without changing the duct layout or duct size fairly soon. Just use one or two short tapping screws at each joint- with metal or PVC duct. In view of the way standard "duct tape" deteriorates over time (fabric self-destructs and falls off while the adhesive hardens and is difficult to remove) and despite its name, regular duct tape is not recommended.
Because DC connections to ww'ing machines are usually 4". For a lot of machines fabricating a DC shroud to fit 6" is neither practical or necessary because reducing the last 3-4 feet does not affect performance enough to matter.
I don't have performance curves (nor do I undertand them) but I will say from my research almost any DC 100CFM and up will perform better with 6" ducts. In my case its a 1 1/2HP Jet DC. I haven't measured the actual CFM at the machine, but in real life it pulls very well from my table saw which is 25 feet from the DC -- and that's with a cyclone. Before I remodelled my shop I had (incorrectly) piped with 4" ducts all I can tell you is the difference before/after was remarkable.
Bill Pentz's website and talking to DC engineers at Oneida and Penn State Industries.
Isn't that what I said? But in actuality, if you read what the experts say, it actually does make a difference, but to me not a practical one.
I assumed everyone knew I was talking about S&D pipe.
Yes screws are better I've done it both ways. Guess the point is don't glue it. I've tried using caulk and had it fail. This is why tape is recommended. HVAC tape is fine but I've always used duct tape. Used it on 3 different DC systems and never seen it deteriorate as you describe (one system was >10 years) even if it did, so what?
I'm sorry if you had problems with what I've said but I believe if you do the research you'll find overall it follows recommendations of the experts. Don't know why, but DC seems to be a subject that sparks debate (I suspect because guys have built a system and reading something that says its incorrectly designed). I've read a LOT of posts on forums about DC and there is a LOT of bad info out there. I based what I said on both practical experience and hours of research. Before building my new system I talked to people at both Oneida and Penn State Industries.
Bottom line: there is a lot of nuance and hair splitting that won't make a practical difference but the biggest mistake I see guys make is undersizing their ductwork. I've seen guys use nothing but a shop vac and 2" pipes running all over the shop and think it works great!
Larger lines reduce the frictional losses incurred for a given length of pipe. A 6" line can move twice the volume of air as a 4" line at a given velocity with less static pressure loss over that distance. As long as the air velocity remains high enough to keep the waste suspended it is indeed advantageous so long as you do not carry such to such an extreme that the air velocity drops too low too keep the waste suspended along it's journey (which can then lead to clogs). It also affords you the opportunity to serve a pair of outlets concurrently where needed, such as at a router table (or a tablesaw with added overhead dust collection, or a bandsaw with lower cabinet and under table outlets) where you typically require dust collection both above and below the table. But that does assume a 6" inlet at the DC inlet, a 6" main line will work against you if you starve it at the beginning by reducing it to 4" at the DC inlet (if necessary, you can often enlarge the DC inlet fairly easily in many cases...it may already be 5-6" since it has the Y adapter attached to the inlet, so such is worth measuring if you have not already). Often times all you need to enlarge the opening is a jigsaw or tin snips to cut a 1" thick band out around the circumference of the existing 4" hole to make it 6", then buy a bolt-on 6" fitting (or make one from wood) to receive your 6" pipe or hose.
What size outlet is your planer? Most that are not 4" to begin with include an adapter that steps it up or down to the common 4" size. Sometimes they will be 2-1/4" or 2-1/2", sized for a shop vac hose (which is silly as shop vacs will fill quickly) but still ordinarily include an adapter that steps the outlet up to 4".
If it is one of the common shop vac hose sizes then you can get a conical reducer that will reduce 4" down to 2-1/2" and use a very short length of hose to connect the conical reducer to your planer outlet. However, if your planer does not include a blower fan (like the DW735) then the restricted outlet may starve your DC of the required air volume to do its job most effectively, in which case you can either drill some vent holes into the reducer or leave a blast gate further down the main line partially open to admit the necessary makeup air so as to maintain sufficient air volume and velocity.
Stal,
I used 4" PVC everywhere for my system. I also built a Thein Separator and it works fantastic! I removed my blower assy and mounted it on the wall about the Thein unit. I blow directly outside with the outlet and so far don't see any signs of any dust getting out. I have a Wynn filter that I used to use and works very well. But by completely opening up the outlet with no restrictions, I greatly improved my dust collection at all my drops. I built my shop (approx 800 sq.ft.) and embedded 4" PVC under the concrete. I don't know where you are located but you're welcome to come to my shop here in Chapel Hill and check out my system.