01-24-2010 12:12 PM
I am planning to build the cyclone dust collector that was in the Nov. '97 issue and was wondering if it would be okay to use a more powerful unit. I have a 2 h.p. ShopFox unit and would like to use the unit from that. Any help will be greatly appreciated. Thanks for your time. -Dan
01-25-2010 01:53 AM
Welcome to the forum!
I can't remember where the muffler mod was, but these were primarily reader's mods submitted to the magazine in various issues.
The most important is the "neutral vane" modification. It's a strange sounding term, but this modification will reduce the amount of turbulence in the cyclone. Reduced turbulence = smoother airflow = higher airflow. You can see two examples of this in issue #141, Apr 2002, page 8. When building the cyclone from scratch, I'd do the method on the bottom of the page which is essentially sliding the cyclone inlet tube (first part of ducting you see in your shop) towards the centerline of the cyclone body. When I get my scanner hooked up I can post a sketch. I'd also angle this downwards a bit to help get the air moving in that direction.
With a 2HP blower, you will want to do a couple things. Use heavier sheet metal than the plans suggest. I used 22ga metal when building my larger cyclone. If I used 30ga then it would have collapsed. The diameter of the inner tube inside the cyclone (the tube that feeds the blower) should be larger than 6" too. 8"-9" would work well with your 2HP blower. Remove the factory blower cover plate and make your own from pywood with an 8-9" opening that matches the inner cyclone tube ("outlet" in the plans).
Now, with a 6" ducting inlet, say 8" inner cyclone tube ("outlet") and an 18" diameter cyclone, you will find the math doesn't work out. 18" diameter minus 8" cyclone outlet tube = 10" left over (5" on each side of the cyclone). You will need to use 6" metal pipe for your cyclone inlet and you will need to squash it a bit to fit in the 5" of space you have available. That will work ok.
For comparison's sake, a "Pentz" cyclone will specify a 20" diameter cyclone for a 2HP blower, 10" cyclone outlet tube and 5" on each side of it. However, a Pentz will also want a round to rectangular transition going into the cyclone and this will convert a 6" round pipe to a 5" wide rectangle that will fit nicely inside the cyclone body. It's a cleaner design with less turbulence. A Pentz cyclone will also have a longer lower cone to make the dust separation be more efficient.
Two other mods in the magazines:
Know when to clean your filter: issue #130, Feb 2001, page 10.
Dust bin mod to see the dust level: issue #105, April 1998
Filter type: Don't use the truck filter in the plans. There are better alternatives now. Wynn carries a nice cartridge filter you can buy. I'm using filters from Camfil-Farr.
My computer hard drive recently crashed so I need to set it up with backups of my cyclone construction pics. I used a Pentz design for the metalwork and borrowed a page from the WOOD mag cyclone for the wooden framework around the cyclone. I can post pics down the road in case you'd like to see them.
01-25-2010 04:19 AM - edited 01-25-2010 04:20 AM
I built that unit and hooked it to my 2.5 HP PSI DC and it worked great. Ran it for over 7 years before I replaced it with a commercial model. I made some of the modificatiosn that Allen mentioned to accomodate the larger DC I was using. I wanted a 6" otlet to match my dc's 6" inlet, so I also upsized the inner vertical pipe to 8". I later retro fitted the neutral vane....taht made a HUGE difference in the way the cyclone worked, and building it in from the beginning makes the construction easier. As Allen mentioned, it does get mashed a little to get past an 8" center pipe, but still worked great. The construction of the unit was much easier and quicker than I thought it would be, and I seem to recall a slight error on the diameter of the lower MDF ring cusing the cone to be slightly smaller. I think I cut a second ring to fit between them, it was no big deal. I didn't mount my blower on the cyclone body, but rather piped the cyclone outlet to my dc sitting on the floor, that allowed me to use the DC bags instead of buying a filter. I don't ermeber the issue with the neutral vane upgrade, I'll have to see if I can find it and post back, unless someone else knows which issue it was in.Good luck with your project!
01-25-2010 04:27 AM - edited 01-25-2010 04:27 AM
Good Morning All,
The changes that were printed were in the very next issue in the corrections article toward the front of the issue. Now as for the number of the issue, I am not sure which one it was.
01-25-2010 08:41 AM
The muffler is in issue #101, Dec 1997, page 8.
Buried in my rambling above is the neutral vane mod, issue #141, April 2002, page 8.
01-25-2010 09:51 AM
Thanks to all for the terrific advice. If any other thoughts come up please let me know. -Dan
ok....here are some random thoughts:
- To help reduce noise transmission to other parts of the house, you don't want to bolt the cyclone directly to a wall. Use either flexible insulators of some kind between the cyclone and the wall or make the cyclone free standing.
- Make posterboard templates of all your metal pieces to aid in layout. Before you cut any metal, use those templates to make a posterboard cyclone to be sure all your measurements are correct. It's worth the time.
- When cutting the metal, be sure to wear eye protection. I used 22ga metal and a jigsaw to cut it out. Jigsaws send metal bits flying so I wore a full face shield. Freshly cut metal edges are really sharp so wear gloves (I like the Mechanix line for metalwork and automotive work) and use a file to smooth the edges.
- If you are rolling heavier metal like 22ga, you will need a round tube of some sort to aid in the rolling process. 22ga was fairly easy to roll over an 8" diameter Sonotube (cardboard concrete forming tube).
- I used wooden rings and nylon straps to aid in keeping the metal round for welding. I've never tried soldering a cyclone.
- For your blower exhaust to your filter, don't use the 5" flex that comes with most 2HP DCs. Keep the diameter as large as possible to your filter. This will help reduce resistance and increase airflow.
- Be sure your dust bin is 100% sealed. No leaks on the lid-to-bin contact area (I use weathertripping). If you have leaks at the bin then air will get sucked in and draw dust into your filter.
That's about it for now.
01-25-2010 10:49 AM
Allan, Once again thanks. My biggest concern was the guage of the metal, I had a hunch that it might need to be heavier. I am lucky that I have a friend who is a sheet metal journeyman to help me with that end of it. If you do get pics or diagrams up in the future, I would love to see them. My time frame is a bit sketchy, but I will try to let you know how iy turns out. -Dan