I'm never without this stuff
I have used this for years for construction projects, inventing, repair, and prototype fabrication. It is the sealant I always wanted silicone to be: tough, adhesive, rubbery, and gap filling. I always have a tube in the shop. I use it for structural adhesive as often as for sealant. As an adhesive, the initial grab is poor, so you have to keep things in place. I've also used it for automotive repairs, when I didn't need the high grab of a contact cement.
Full disclosure- I haven't used this on
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construction projects very much, so I can't testify about longevity, sun resistance etc. But it's paintable, and it seems like it would do a great job.
My cautions are really the flip side of what I like about it.
This has lots of working time, and is easy to handle. For the first day, however, it remains sticky, and is pretty weak. Don't be fooled. The strength builds up over time- it becomes very strong, tenacious, and flexible. Curing is triggered by exposure to water vapor, so a slightly moist environment speeds it up some- but thick sections may take days to reach full strength.
It sticks to everything, except waxy plastics like PE, PP. But- that stickiness and easy texture makes it easy to get on your to your clothes, shop bench etc.. Be thoughtful and work slowly. Nitrile gloves are a good idea- unless you like black, sticky fingers. I apply it to small projects with popsicle sticks or bamboo skewers, work over papers and try not to touch it. Some folks are sensitive to Urethane- it has never bothered me.
It foams up slightly- maybe 10%, which is usually a great thing for filling in gaps, but can leave your brilliant caulk gun artistry a little bumpy. For sealing, it is just bulletproof.
Cleanup with mineral spirits seems odd- it never worked at all for me. I found that 91% isopropyl (rubbing) alcohol seems to work much better, and can even be used for smoothing the surface of the uncured sealant. Clean up right away- otherwise no solvent works.
Trim after it loses tackiness, but before it gets to full cure.
Hint for re-using the tube after a small job: After the first job with a new tube, cut the tube tip off removing the pointy end altogether. Then let some sealant ooze out, maybe 3/8" past the end of the tube. That oozed sealant will cure into a tough and flexible handle. If you need more sealant later, pull the sealant handle slowly. You can usually get a plug of cured sealant out of the nozzle, even a few weeks later. That opens the tube for re-use.
BTW, their PL urethane construction adhesive is also one of my favorites, a must-have, for rigid joints and good gap filling with odd material.