Blast gates - video

[Jon]

Blast gates. By Monochrom Workshop. 26:47 video:

[hemmjo]

The gates look nice, but you been to be sure you do not restrict the flow so much that the velocity falls off in the larger main line. If the velocity falls too far, the debris falls to the bottom of the duct and can some restrict flow.

[Frank S]

My question is why go to all the trouble to buld the blast gates wouldn't an RV black water dump valve do the same thing. It is already air and watertight.

[WmRMeyers]

My question is why go to all the trouble to buld the blast gates wouldn't an RV black water dump valve do the same thing. It is already air and watertight.

I've not been all over the world, but have been in Northern Europe, and portions of North Africa and Southwest Asia, and not seen anything like RV black water dump valves there. Though it was, admittedly, over 25 years ago. No telling what they have now. Dude has some pretty neat stuff in his junk pile, too. Maybe he just wanted to show it off? I've got a few bits and pieces of air valves and such scavenged from the dumpster at work before I retired, but my stuff LOOKS pretty well used and abused.

He's quite the craftsman, though. Doubt most of my stuff will look anywhere nearly that neat, clean, and professional.

Bill

[Frank S]

Something like this is what I am talking about since it already has tight seals there will be no vacuum loss they can be bought in sizes ranging from 1 1/2" thought 3" openings. I haven't seen anything larger than that until you get into industrial quality valves.
Yes his craftsmanship is above reproach.

Inexpensive models have the simple pull handle, but you can buy these valves with 12V and air powered opening and closing attachments.

[hemmjo]

Down side of those plastic valves would be erosion of the valve by abrasive dust. He uses it wood and metal shavings. Even just wood chips would erode the plastic valve