I have sealed my MLD Duomid yesterday using Permatex Flowable Silicone 81730. Got a tube (x2) at a local Autozone ($5). I am satisfied with the results. The silicone is not nearly as flowable as diluted silicone I have seen in youtube videos, but eventually flows more than sufficiently. I used a foam brush from Home Depot, suspect a regular stiff brush would have worked too.
I started working late, outside with temps in mid 60-ies. In these conditions silicone does not dry as quick as labeling suggests. I finished quite a bit after dark and eventually put a heater fan inside the tent and then drying went very quick.
Bonding of the Permatex silicone to silnylon is amazing. I tried to scrape off an accidental drop, not quite cured, but could not do it even after 20 minutes. I have in the past used seam sealer bought at REI specifically for sealing silnylon (to seal some dry bags) and that stuff comes off way too easily. Also, required some talk powder to get rid of tackiness.
The tent weight went up by about 20 grams (2/3 of an ounce). I could have probably used less sealer. There are a few places with too much sealer or too wide around double seams.
The bottom line, Permatex Flowable Silicone 81730 gets thumbs up. The process is not too easy, but the results are good. If I were to do it again, I'd try to use less silicone and more brush spreading action.
Best technique is to use the nozzle to squeeze silicone along a seam a few inches at a time and then spread with the brush.
