This shutoff/blast gate was originally designed to fit inside 4" flexible tubing for dust collectors. But due to popular demand from many of you lovely people, it's now been updated to include all kinds of sizes of tubing!

You'll need to secure the tubing using a band clamp to the outer portion of the circular extrusion. There are four main pieces - (1) the blast gate, (2) the spacer/middle section, and the (3) left and (4) right side pieces (these last two have the mating pieces for the tubing). Some may choose to call them "top" and "bottom", rather than "left" and "right", but it depends on your setup and how you mount it. For my friend who I originally designed this for, it was mounted in horizontally, rather than vertically.

The gate is designed to be assembled with 4x #8 screws, 5/8" long, each with a #8 nut, which will be captured on the back side of the unit (on the "Right" side piece). In the photos, I was using an odd-sized screw/nut combo that was a bit longer than the prescribed screws (hey, it's what I had on hand!). An official #8 machine screw that's the right length should fit perfectly. :)

NOTE: I designed the Fusion360 model in such a way as to make it easily scale up/down from fitting a a 4" tube to other sizes of tubing. If you are interested in me uploading a different size of tubing, please let me know! Drop a comment or a direct message to me. I'd love to hear from you!

Please also post any makes! I'd love to see everyone's different setups!

UPDATE: ADDED A 2.5-INCH VERSION!
Upon request, I have added a version of the design to fit a 2.5-inch diameter hose. I have not printed this version or tested it, but it should work - all dimensions were based off of the hose diameter, so shrinking that will bring everything else into alignment. If you do end up doing a print, please post a make of this new version! I'd love to see it and get feedback on if it works properly. If it doesn't, please let me know what needs to be changed and I'll make the necessary alterations.

UPDATE: ADDED A 125-mm VERSION
Upon request from a user on Cults3d, I have uploaded a 125-mm version for anyone using metric tubing. I'm not sure what the smaller version of that is, but if someone needs it, just let me know and I'll make a version for that size as well.

UPDATE 2024-03-19: ADDED 8-inch & 10-inch VERSIONS
Upon request from Thingiverse user @galertstbm, I have uploaded TWO new versions - an 8-inch and a 10-inch version for some huge suction-stopping action!! Note that there are more bolt holes around the edge of the gate to support the now-longer sides of the unit. A total of 6 additional screws and nuts (10 total of each) will be needed to assemble these larger units.