been a while since i updated here. past several days have been more drywall and preparing portions of the ductwork to be coated on the inside with the vibration-dampening stuff. seeing as how drywall is phenomenally uninteresting, i'll skip that and go straight to talking about the ductwork.
i picked up an air compressor last week and a spray gun to use with it. over the weekend i used these to apply the requisite metal primer to the insides of all the ductwork. it should've taken about 24 hours to dry, but with the weather cooling off and me being a doofus and leaving everything right by the garage door to dry, it ended up taking more on the order of 48 hours to dry to my satisfaction. i also made a complete mess in the process and got primer everywhere.
after much procrastination, i decided to work on the first vibration dampening coat. the manufacturer recommended using a spray gun to apply this stuff, and they even sell a "blessed" spray gun, which i went ahead and bought. as i opened the container and began mixing it up with my drill/power mixer, i realized that this stuff is about the consistency of caramel. quite literally if you were to combine 1 part gray latex paint with 1 part heated caramel, that's exactly the appearance and consitency of this stuff. even though they say repeatedly in their literature that this stuff is very thick, it wasn't until i opened the container that i was able to fully comprehend what that meant.
imagine, if you will, trying to spray caramel onto something. that will give you some idea as to the level of success i had with trying to get the compressor to siphon this stuff out of the spray bottle. it just kinda sputtered out of the tip in tiny specks like some sort of robot porn money shot. i just gave up and switched to using a brush.
the main problem with using a brush is that it makes it kind of hard to do a good job of applying thick layers, which is what this calls for--ultimately i need it to be about 1/16" thick to function effectively. after not being able to get things sufficiently thick with normal painting, i decided to pull out my sloppy painting skillz again, pour a whole bunch of the stuff right onto the ductwork, and use the brush to kind of smear it around and get as even a coat as possible. this actually worked out better than it might sound. i have two pieces of ductwork of equal length, one completely uncoated and the other smear-coated. if i pick up the uncoated piece by a corner and tap it, it rings out for quite a while. the coated one dampens right away. i tried the same thing on the original 2 pieces i did with just normal brushing, and those behaved about the same as the uncoated piece. as the stuff dries and cures, its dampening abilities improve significantly, provided the application is sufficiently thick.
even though the brushing technique mostly worked, it's a bit of a kludge and i'd still like to try and find some way to spray this stuff on for the remaining coat(s). i'm going to investigate airless paint sprayers tomorrow. i may also experiment with adding a tiny bit of water to thin the mixture out a bit, which the literature says can help a little as long as the amount of water added is kept very minimal.
