Separator with Harbor Freight DC and 4" pipe - success!!!

[windmill]

I built my own trash can separator, using particle board for the lid. It's a 40 gallon can, metal, with the hoses attached to the lid via PVC fittings. The dust collector I'm using is the Harbor Freight "2HP" model, with a Wynn cannister. My shop is pretty small, the longest run I have is ~25 feet.



The results of the separator (without modification) were so-so. At first, I still had to empty the bag as often as the can, the "scrubbing" was awful. By tweaking the size of the pipe inside the trashcan, I was able to improve this slightly, and now I could fill up the trash can twice before having to empty the bag. Better, but not great.

I built the baffle from your design out of some particle board (5/8"). Probably overkill, but it made it easier to seat the dowel spacers, and I also happened to have some left over from a previous project. Construction was very simple using the pictures posted on your web site. A router, a Forstner bit, glue and screws: DONE!



The results are nothing short of spectacular! I haven't done any formal testing, but 95% (if not more) of the dust now stays in the trash can. Only the very fine dust ends up in the bag. And it is MUCH easier to empty the trashcan than emptying (or replacing) the bag. Getting the metal buckle around the bag can be a tricky job, only having to empty the bag once a blue moon is a real lifesaver! In the pictures below, the trash can is about 2/3 full. The dust in the bag is minimal, maybe 2 cups (if not less).




I can't believe what a tremendous difference this modification has made. The two hours I spent making it (including cleanup and shopping for the materials) will be recouped within a couple of weeks simply by not having to hang a new bag. Thanks for sharing the design! You should definitely pursue your patents, or at least recover some of your investment by selling plans on building a better separator.

Bas.

[phil (admin)]

Nice job.  I hope you'll keep us updated with your observations from continued use!

[Hobkirk]

Windmill -

SPECTACULAR pictures and comments! Thank you very much! Naturally I have some comments...

• Your testing is simple but exactly what I want to see.
• You used 4" fittings, answering my about-to-be-asked question.
• I thought the IN port outlet was supposed to line up close to the start of the 120 degree extension, but I see that Phil's new design doesn't either.
  
• You also have a lot more "breathing room" than Phil, which might make it a little easier to construct.

You have answered all my questions. Your results are so spectacular that I see zero reason to experiment.





Thanks for making my life easier!

[phil (admin)]

I thought the IN port outlet was supposed to line up close to the start of the 120 degree extension, but I see that Phil's new design doesn't either.

The elbow should be under the major radius of the baffle to prevent turbulence from picking-up dust from the bin (especially as the bin approaches capacity).  Bas (Windmill) probably could have extended the large radius from 120 to 160-degrees given the size of his fittings.  Perhaps someday when he has time he can experiment and let us know.

You also have a lot more "breathing room" than Phil, which might make it a little easier to construct.

Also reduces SP.  Separators are all about tradeoffs.  More room on top means less room on the bottom (for chips).  But it also reduces the CFM hit.

[windmill]

Regarding the placement of the elbow - yes, it would probably be better if it was situated at the start of the outer rim. But, the baffle was added to an existing lid. I had originally placed the elbow at an angle so that it would spew the dust against the side of the trash can, to reduce the velocity and get the dust to drop quickly. With the addition of the baffle, that's no longer needed, but the elbow is locked in place. I was worried that because of the angle, the dust would lose too much velocity to travel the full distance to the drop slot, so I moved it slightly forward. I do have a small insert in the elbow I can remove (this is a 3" piece of PVC pipe). Hopefully, this will further improve things.

I'm using a big trash can (40 gallons). I don't want it to fill up all the way, since it will be too heavy to carry out. The extra room made it a little easier to construct as well.

I might build another lid one day, it's pretty easy to do. I know of several other people that are working on one as well, I'll ask them to post the results here.

[phil (admin)]

I'm using a big trash can (40 gallons). I don't want it to fill up all the way, since it will be too heavy to carry out.

Isn't that what wives are for?