I was not very happy with my dust collection run and blast gate solution the last time around. So I put some thought into how I would make it better this time. First was I wanted gates that wouldn’t get clogged, and second I wanted to be able to easily open and close them without reaching under the bench. The first part was easy, I found some no clog gates a while back at WoodCraft.
As you can see I have drilled a hole on the side of the gate opposite of the wall. I am using a 2ft length of threaded rod and I have used three nuts to capture the rod on the gate. I then put the top back on the cabinet frame and drilled a hole through the top for the rod to go through. So you can guess my thinking is to use the rod to lift open and push close the blast gates. The challenge is gravity, when you lift up on the on the rod the gate it works as expected , but when you let go of the rod it falls back down and closes the gate. So I thought about several different solutions but this is the one I came up with. I bought 4 small Bessy spring clamps from the blue borg. I opened the clamp up with a piece wood that made the jaw roughly parallel to each other, and I then drilled a 15/32 hole as close to center on the end of the clamp as possible. 
I then repeated this on the side of the clamp. You now should basically have a hole through the clamp. You should then open of the jaws of the clamp and place it over the threaded rod. I used my test clamp to keep the jaws open. I then pulled the rubber grip off of the bottom handled and then used a 1 1/2” screw with a finish washer through the hole in the handle. On the jaw end of the clam I used a flat washer and a Pocket Hole screw to hold the end of the clamp down onto the work bench. The main thing to be careful here is to make sure the bottom hole is not touching the threaded rod. 
As you can see in the picture with the jaws closed the threaded rod is now in a bind.
To open the blast gate you would press down on the handle of the clamp and then use the handle on the threaded rod to lift up and open the blast gate, you would then let go of the clamp handle which would close and bind keep the handle in the up position, to close the gate you would just press down on the clamp handle and the threaded rod will fall closing the blast gate.
Let me know if you have any questions!