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Hi I am a new member and need some info. I am going to install a new dust collection system I have a delta 760 1 1/2 hp. The inlet for the 760 is for two 4" or 1-5". Everything I read say to use 6" or bigger pipe. The inlet is only 5" would you still need to use 6" or bigger pipe for the main line. Thanks inadvance for any info.
:smile:
 

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Hi raymondb

Your dust collection system sizing depends on what equipment you are running. Smaller items can be easily handled with 21/2 inch tubing. Bigger units, such as planers/jointers, will require 4 inch. Run your tubing through a cyclone collector first, to drop the bigger items out before they get to your bag. That will save a lot of time emptying the bags, as the cylone lids sit on top of a garbage can.

Gerry
 

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Thanks Gerry for the info. The main equipment I would be using the dust collection for are table saw, miter saw, jointer, and sanding center. All will have waste gates attached.
 

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Hi raymondb

Your 11/2 hp system should handle those pieces of equipment with no problem. I am running a 21/2 inch system with collection tubes tied into a 11-1/2 gallon capacity, 5 HP Shopvac. I run my sander, tablesaw,bandsaw through this. I still have to add the cyclone lid, as the Shop vac has a bag system, which I don't want to be replacing too often, due to cost. I purchased a 1 HP sawdust collector for use with the planer, and jointer. Here again, I have to add the cyclone. The sawdust collector has a 4 inch hose. I find that the cross grill on the motor inlet tends to clog up, which is why I want to add the cyclone. I have also added an aircleaner, to recycle the air, and catch the fine dust from the shop air. I also still have to get together some dust collection hoods, etc. for the equipment.

Gerry
 

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Hi raymondb

Your 11/2 hp system should handle those pieces of equipment with no problem. I am running a 21/2 inch system with collection tubes tied into a 11-1/2 gallon capacity, 5 HP Shopvac. I run my sander, tablesaw,bandsaw through this. I still have to add the cyclone lid, as the Shop vac has a bag system, which I don't want to be replacing too often, due to cost. I purchased a 1 HP sawdust collector for use with the planer, and jointer. Here again, I have to add the cyclone. The sawdust collector has a 4 inch hose. I find that the cross grill on the motor inlet tends to clog up, which is why I want to add the cyclone. I have also added an aircleaner, to recycle the air, and catch the fine dust from the shop air. I also still have to get together some dust collection hoods, etc. for the equipment.

Gerry
Hi Jerry.
On your 5 hp shopvac on the discharge side were the air blows out, is this the hose line you put into your cyclone lid ? Sorry for the stupid question but I am trying to set my 5 hp vac up now and I have the suction side to my tablesaw however there is alot of dust coming out on the discharge side. It's like I am getting all the dust out of my tablesaw but putting it back into the air of my shop.:no: thanks for any help.
 

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Hi Bruce

THe bulk of the bigger chips should drop into the cyclone bin. The finer dust should be picked up by the bag in the shop-vac. If you find you are still getting a lot of dust coming out your dischage port on the shop-vac try installing a new bag. "Shop-vac" has bags available which are designed to capture more of the dust than a standard bag. I believe they are designed for drywall work, where the dust is very fine.

Regards

Gerry
 

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Hi Bruce

THe bulk of the bigger chips should drop into the cyclone bin. The finer dust should be picked up by the bag in the shop-vac. If you find you are still getting a lot of dust coming out your dischage port on the shop-vac try installing a new bag. "Shop-vac" has bags available which are designed to capture more of the dust than a standard bag. I believe they are designed for drywall work, where the dust is very fine.

Regards

Gerry
Jerry.
Thanks you know I don't even have a bag in my vac:oops:
 

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Ah So

That would possibly explain the dust coming out of your discharge port. Glad to be of help.

Gerry
They do not make a filter bag for my vac it just has a filter however I will find a way to get a bag on that puppy. I have a Ridgid 5 gal vac and I keep the filter clean but I will try to put some kind of bag on it thanks.

Bruce.
 

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Hello all. Great site.

There is a lot that goes into dust collection design. You have to look at air speed, air volume and static pressure. For heavy chips, from a planer, you want higher speeds to get the chips air born. For sanders, you want large air volume to move the large amounts of dust. Static pressure will tell you how much of these two ingredients you need at the dust collector in order to end up with the correct amounts at the tools.

What we want to do is maintain our airspeed around 4000 FPM to keep our duct lines and tools free of debris. FPM = CFM/Area (The Area is the area we are collecting from.) If all we are dealing with hobbiest type tools, 350-450 CFMs is our goal for most equipment. If dust collection is a prime concern, we want to double that. Manufacturers, like Festool, design their tools from the ground up to direct airflow around the cutters, increasing effectiveness. In which case, the 350-450 will not only collect the large chips, but also the fine dust. However, most of us have shops loaded with tools that have large opening around the cutters, so we need to double the air flow to not only effectively collect the chips, but also the fine dust. It is the dust that leads to breathing problems. If you are not concerned about health issues related to dust production, and I will assume most here are not, we will ignore the x2 rule, and just stick with a targeted range of 350-450 CFM, it makes everything much more simple. To save some space, let me say it takes a minimum of 50 FPM to move fine dust. Just keep that in the back of your mind. We want 4000 FPM at the cutter to pickup the chips and at least 50 FPM around the cutter, think of a sphere, to capture the fine dust particles the best we can.

A 2.5" vacuum hose only supports 136 CFM at 4000 FPM at the "muzzle". This turns into 50 CFM just over 5.5" away from the "muzzle". To test it, just lay your hose on the ground and turn on your vacuum to see how far away it picks up dust. That is why shop vacs make poor dust collectors. They have a very high air speed but a very, very low air volume. The DC mentioned in the original post with a 5" duct, supports 545 CFMs at 4000 FPM and 50 CFM out to about 11". In other words, if you run a 5" duct to the back of your table saw, and the connection is more then 11" away from the top of the blade, you will catch the chips that fall to the bottom, but not the fine dust that blows in your face.

I could keep going for many pages about this, but it would be very boring. To get back to the original post, your particular DC isn't sized to handle an entire shop. Try to find the fan curve for your DC, a search on Google might turn it up or ask the place where you bought it. If you still have the manual, it may be in there. What the fan curve tells us is the CFM at a given amount of static pressure. The longer the run of ducting, the more static pressure in your system. Static pressure is bad. Every time you add a component such as an elbow, y-fitting or the chip separating cyclone bin, you increase the static pressure and you will see huge drops in CFMs. Just as an example, 2 90 degree elbows, 15 feet of straight ducting with 3 feet of flexible ducting and a chip separating cyclone bin, has over 9.5" of static pressure. Using a 2 hp cyclone DC as an example, 9.5" of static decreases effective CFMs from over 1400 CFMS down to 600 CFMs.

Sorry for the long post. I will stop now. If anyone wants more info, I have a ton. But, in summation, if you are serious about dust collection, especially if you are concerned for your health, you need to size your dust collection appropriately.
 

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Hi Tippy

Good post. Don't apologise for being a little lengthy. Even the most experienced of us are still [hopefully] learning, and it is a sad individual who declares "I know it all". And, welcome to the forum. Dust collection is indeed a subject all into it's own, and we are all learners with regard to that. It is a subject that has been disregarded for years, because almost nobody realised the potential, and long term damage. [ kind of like smoking]

Best regards;

Gerry
 
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