Recently upgraded to a cyclone and built a closet for it. I thought I'd pass along a few observations. I built it more or less along the lines of construction that many have discussed here. Walls are 2x4. Inside on walls is 5/8 sheetrock since I had some left over taking up space. Doors are shop made 2x4 also, skinned inside and out with 1/2 osb. Outside of the walls are 1/2 OSB also. Walls and doors are filled with Rockwool Quiet Batts. Return air is through the ceiling joist spaces, which I also lined with Rockwool. I had intended to baffle the return air area and also weatherstrip the doors, but when I fired it up it was more than quiet enough for me. Sure, you can hear it from in the shop, but the sound of the air rushing through an open blast gate is way louder than the drone from the DC itself. You can barely hear the DC if you are in the rec room outside the shop or in the bedroom above it. I have no trouble having a normal level conversation when standing next to the closet.
The last picture shows my shop made drum roller. I thought the Oneida version was overpriced, especially since you have to add the leg extensions to use it. I took a scrap of plywood and added some $10 low profile appliance rollers under it. It fits without blocking up the legs more than the 1/2" rubber isolation pads. It only rolls in one direction, but that actually makes it easier to get the drum lined back up after emptying. I'm thinking of adding 4 extension springs from the drum lid to the frame cross members so when the drum clamp is released the lid is lifted slightly by the springs. Then the drum could be rolled out without fussing with holding the lid out of the way.
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