After I did the Bill Murray cleaning job on the shop I am really unhappy with my dust collection setup. I really didn’t finish the job adequately when I installed it and I also am not getting enough cfm out of the system. I use two of the HF dust collectors hooked in tandem. One inside and one outside. By closing off the blast gates I can use either one by itself or both. This allows me to close off the outside one in the summer to reduce the cold air extraction. I use 4” pvc ducting. So the rehab starts with duct taping all the couplings in the system. Something I should have done a long time ago. After that I’m changing the filters on the dust collectors to increase the flow. I ordered the Wynn canister kit for the inside collector. It currently has a 1 micron felt bag on it and the canister should give me a lot more air flow. The outdoor one is a different animal. I decided to experiment with a much larger micron filter. The current one is a 30 micron filter bag. Today I changed it out for a much larger micron filter ie window screen. Suddenly the flow is amazing. I did it as kind of an experiment just to see what would happen and how big of a mess would result. It actually works really well. It seems to trap all the wood chips ( ones that won’t fit though the window screen) and the fine dust just dissipates out into the desert along with all the other dust. No lack of dust here in the desert. The flow is way more. The closed dust gates are whistling. 
Paul

I wish mine was outside, but only have one and it is in the attic

I'm a poor one to comment on proper dust collection as my system is woefully inadequate. I have a Delta upright collector- filter bag on top and plastic collection bag on the bottom. I hate to empty the plastic bag. I found plans for a Thien separator using a metal garbage can and the plastic lid from Woodcraft. All but the finest dust goes into the garbage can. Probably only empty the bag once or twice a year

I did a system like Danl described in his post.  Mine is mostly the same, except not as pretty.  The cyclone takes care of most of the dust with very little in the final bucket.  I used the original HF base and built up from there.  The 10 mil pvc tape worked well on the joints. 

 

Big improvement over the out-of-the-box setup.

 

 

Mine is roll around unit.  Has the large Dust Deputy which is well worth the money. 

 

I built a box from Shop Notes plans

 

 

 

And recently added a 5 inch Dust Deputy