Home Built Blast Gates

[Peter Hartman]

I was going back and forth whether I should buy commercially available blast gates or build my own. I finally decide to try to build my own. I decided I would make them out of scrap I had laying around so my cost on these was virtually free vs $11+shipping for the others. These are 6 inch but I think it would fine on a 4 inch system also.

I started out with 3/4" advantec flooring material. I cut it into 7 and 1/2" squares and marked the center.
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Then I made a little base for a trim router and used a cutting bit and made some 6 1/8" holes.
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https://lh5.googleusercontent.com/-bQghr6X87LE/U_UgZSpjFPI/AAAAAAAAbD8/SDVLr6Qn9GU/w864-h648-no/IMG_20140820_172532.jpg

I used a dremel in a little jig to cut some 2 3/4" pieces of 6 inch hvac ducting. Then I drilled and screwed the ducting pieces into the holes.

https://lh4.googleusercontent.com/-wWySYbJNxCs/U_UjjOW_8oI/AAAAAAAAbEI/wOaeiA6k5M4/w864-h648-no/IMG_20140820_173859.jpg


Once that was done I glued and screwed some roughly 3/4" strips sandwiched into 3 sides of the boards.

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I found some 1/2" zip board and cut it down to size. I left them about an inch long and cut them about 1/8" small so they would slide easily. Then I used contact cement and attached some window foam.

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https://lh5.googleusercontent.com/-rz22OZyebbk/U_ZjVoXzYwI/AAAAAAAAbFU/1Rsguzb2Zr0/w864-h648-no/IMG_20140821_162326.jpg


I crimped one end and sealed everything up with some foil tape.

https://lh5.googleusercontent.com/-IOTHxKziXP8/U_Z24vA7S1I/AAAAAAAAbF0/-bfz9a0bkwg/w864-h648-no/IMG_20140821_174648.jpg

[John Lifer]

Good job. I think the foam is unnecessary, going to wear and leak. Maybe more with foam than without. Vacuum will pull shut off against the board well enough. My cheap aluminum with sheet slides leak more than wood on wood.

Now you can figure out how to automate them :)

[Jim Andrew]

Looks like a simple, usable plan. Thanks.

[Larry Fox]

Nice design. I used a slight variant of this plan. http://benchmark.20m.com/articles/BlastGate/blastgatebuilding.html