Cyclone Dust Collection

A cyclone is definitely the way to go, but I think you will be up sizing the blower horsepower before long. You will probably also be having fits trying to get a leak tight seal on that metal trash can lid. Although metal trash cans are easy to find, they tend to be hard to seal the lid and seams when using them for this purpose. I went with a metal grease barrel because the barrel has welded seams and a smooth top lip to seal to the lid. When running, any leak in the hose connection or barrel below the cyclone will significantly reduce the efficiency of your system, and it will also result in considerable amounts of dust and chips getting past the cyclone and into your filter bag. A cyclone depends on no up air flow from below or the dust and chips won't fall out the bottom of the cyclone into the collection container and some will end up getting past the cyclone.

I used some 1" wide "closed cell" foam Weather stripping applied where the lid of my collection drum and the drum top edge come together with the sticky side of it attaching it to the lid. I carefully cut the two ends of the Weatherstrip at the same time using a razor blade, so there is no leak between them. The vacuum pulls the lid tight to the barrel when it's running, so I haven't needed any mechanical fasteners, just gravity keeps the lid on when the vacuum is turned off. I used a smoke generator held close to possible leak points to see if I had any leaks after I had assembled my system. They sell smoke detector test spray that works well for this. A smoldering piece of clothes line rope works, but don't use it if you have any dust or wood chips in the system because a spark from it might be drawn in. The smoke spray is the safest and most reasonably priced way to test for vacuum leaks. You need to spray it near the possible leak and then watch to see if any is being drawn in. Use good lighting so you can see if this is happening. Leaks in the joints of your system can be found the same way. The HVAC guys use a rubbery paint-on sealer for duct leaks, or you could just use the silver duct tape and carefully apply it to avoid wrinkles which might leak. Any leak in the pipes between your machines and the cyclone will reduce the vacuum level at your machines. With only a 1 1/2 hp system you can't afford to have any leaks or efficiency losses.


Charley

I have a 4" garbage can topper I got at Woodcraft with a 30 gallon steel trash can. It works pretty good at keeping out the big chunks and I get a lot less fine dust in my Jet 1.5 HP dust collector. A real cyclone would work better but there are the limitations of time and money.

I also have a Onieda dust deputy for the shop vac (2") and that works great at keeping the shop vac from becoming clogged in 5 minutes or less.

Since I have a pre vortex Jet retrofitting if the most cost effective. If I did not have a dust collector then I would definitely spring for a cyclonic type dust collector. The technology of the cyclonic is much more advanced than the old bag and blower type collector and even with the fancy pleated dust filter the cyclone beats that older technology.

For any dust collection system to be effective it has to work near peak vacuum. The cyclonic action keeps your filter cleaner longer and leads to better dust collection. Better dust collection leads to better air quality. Small dust particles are dangerous especially if you already have respiratory issues.

As Ben Franklin said " A stitch in time saves nine". Better to prevent breathing problems than treat them later.

Got the floor epoxied in the secondary part of the shop... What a big change between old and new. Also, got a better seal on the can lid and a 6" flex hose between the cyclone and dump lid. I'm impressed with the suction when two blast gates are open at the same time. Now all I need is a cartridge filter sometime down the road...

CharleyL said:

A cyclone is definitely the way to go, but I think you will be up sizing the blower horsepower before long. You will probably also be having fits trying to get a leak tight seal on that metal trash can lid. Although metal trash cans are easy to find, they tend to be hard to seal the lid and seams when using them for this purpose. I went with a metal grease barrel because the barrel has welded seams and a smooth top lip to seal to the lid. When running, any leak in the hose connection or barrel below the cyclone will significantly reduce the efficiency of your system, and it will also result in considerable amounts of dust and chips getting past the cyclone and into your filter bag. A cyclone depends on no up air flow from below or the dust and chips won't fall out the bottom of the cyclone into the collection container and some will end up getting past the cyclone.

I used some 1" wide "closed cell" foam Weather stripping applied where the lid of my collection drum and the drum top edge come together with the sticky side of it attaching it to the lid. I carefully cut the two ends of the Weatherstrip at the same time using a razor blade, so there is no leak between them. The vacuum pulls the lid tight to the barrel when it's running, so I haven't needed any mechanical fasteners, just gravity keeps the lid on when the vacuum is turned off. I used a smoke generator held close to possible leak points to see if I had any leaks after I had assembled my system. They sell smoke detector test spray that works well for this. A smoldering piece of clothes line rope works, but don't use it if you have any dust or wood chips in the system because a spark from it might be drawn in. The smoke spray is the safest and most reasonably priced way to test for vacuum leaks. You need to spray it near the possible leak and then watch to see if any is being drawn in. Use good lighting so you can see if this is happening. Leaks in the joints of your system can be found the same way. The HVAC guys use a rubbery paint-on sealer for duct leaks, or you could just use the silver duct tape and carefully apply it to avoid wrinkles which might leak. Any leak in the pipes between your machines and the cyclone will reduce the vacuum level at your machines. With only a 1 1/2 hp system you can't afford to have any leaks or efficiency losses.


Charley

Click to expand...

Sealing the lid is very important unless you don't mind sawdust in your filters. I used the widely available foam tape that's 1-1/2 to 2" wide and put in on the inside lid perimeter. Several layers and haven't had a leak since. In fact it's so tight that when the 30 gallon galvanized can is empty my CV1800 lifts it off the floor. But mine is 16" steel impeller and 5 HP. As for leak testing I used a gallon paint can (new/empty) and used a plastic hose to direct the smoke from the incense I burned in the can. Puts out smoke and smells good as well. I did use 3" metal tape to seal all joints. See my DC system here and here Notice the first picture on the second page. This is the results without a good can lid seal and that filled the filters about 1/2 way up. What a mess. What isn't pictured is the safety switch I installed to shut down the DC if it fills and also gives a strobe alert as well as a horn. See this for more info. You could build a simpler version without the strobe light and using standard garage door sensors and a relay which is basically what the garage door safety circuit does. Depends on your level of skill. Really needed, well at least highly recommended anyway, if you DC is out of eyesight of the shop area.

The way my 30 gallon galvanized can lid was sealed with that 1-1/2" rubber foam tape as described in my first post, when the system is started the can is literally lifted an inch or so off the floor if empty. Having filled those stacked filters once before taught me all I needed. I also used a self taping screw that had a washer like feature to firm up the pipe and fittings connection. None is glued. Over the screws,usually 2-3, I used 3" metal tape which seals extremely well. The idea is to have it where it can be altered if needed in the future. When installing my CV1800 I was advised not to use tees but rather wyes to maintain the cfm. They had also advised having as much straight pipe possible before entering the cyclone itself. I ended up using almost all 6" PVC and reduced to 4" at the closest point I could to the equipment. One of my biggest complaints with the manufactures of the fittings is both in sizing and style. Seems that the fittings are sized either for the pipe or the hose. Problem is with PVC, different types of PVC have different outside diameter. What I used was the recommended "green" PVC SDR-35 but depending on where you live there seems to be other choices. Some of those are a more narrow outer diameter (thinner) while others are thicker. So fittings need to be considered before buying and running the pipe. Make sure you can get the wyes and preferably 45s instead of 90s as well as any other style fitting you may need.

As to getting the wire reinforced hose there are a number of ways to persuade it to go on the pipe. Sometimes using a heat gun will help stretch the pipe enough, sometimes you may need to carefully cut the wire out of the end section enough to fit over the pipe 3-4" and clamp, sometime both are needed. A loose fit and you'll end up with sawdust packing the void from where the clamp closes down on the pipe.

As for fittings, I'm surprised at what's available. Most adapters I've seen for 6" to 4" are like stacked cans. Meaning that the 6" part is like having a flat end with a 4" hole and tube which causes a good deal of turbulence which is the last thing you want. A conical transition from 6" to 4" is far superior. If you are considering running a piped system then I think it's best to have a drawn plan and sketch out how you would run the pipe. Then do an estimate of all the parts needed to install and go to your supplier and actually make sure they have, or can get, the fittings you need. Actually fitting those to a piece of pipe will make sure they will give you what you need. Had I not been installing this by myself I probably would have gone with Schedule 40 PVC as it seems to have a more available selection of fittings but it is heavier. The very thin wall pipe wasn't available in my area at all. SDR-35 was a compromise but worked well after hunting done what wasn't found locally. If budget wasn't a concern I would have used the snaplock metal pipe that is made specifically for dust collection systems. In that case you'll likely spend far more in pipe and fittings than the DC equipment itself but it will be a very nice system.

tulowd said:

Hey Tom:

Which Rikon impeller did you use and did you order from Rikon directly?
Also, what cyclone design/build did you go with in the Uline 30 gall drum?

Asking for a friend, lol!!!

Thx Young Man

Click to expand...

I'm still using the original impellers. I can't seem to find the part number. I mentioned it because someone here did a whole long series on the topic. It dramatically increased the CFPM according to his tests.

I have the 5 - 6 inch Super Dust Deputy now. I placed this in a sealed in space between my shop shed and office shed. This allows me to return the filtered air back into the shop. The picture shows the setup. The collection hose if flexible 27 ft Rockler hose. It goe to a through the wall port into the chamber, into the cyclone which is set on the drum. The air then goes into the HF DC, then out through the drum filter. It returns through another 20x20 filter (upper right) back into the shop. Since the picture was taken, I've shortened and straightened the hose from wall to cyclone and sealed the heck out of everything. Works well and I get my heated, cooled air back, which is good in our HOT COLD desert climate.

Pix one shows the old setup with the rockler chip collector, the other shows the new setup. That hose connector up front is now much shorter (14 inches) and straighter. You can see the return air vent and filter in the upper center. This chamber is about 52 inche wide and about 8 ft long. The chamber is pretty well sealed to retain as much cleaned air as possible. Some day I dream of engineers making connectors and ports to specific sizes so the fit together easily.