Originally Posted by sailboy21
Would life-caulk cure in time? It looks like I am going to be on the grid for about 12 hours. The next high tide isn't high enough to float off. Weather looks like chance of rain. Highs 45 low of 36 Shorepower is available so I could use a space heater if necessary at least inside the hull.
We answered this question last year in another post you made about tide grid & changing of seacocks.
Here's what I wrote last time after calling both 3M and Boat Life..
I called both 3M and BoatLife and spoke with tech support about cure times & launching. I did this because neither site really specifies launch time's or windows before launch and I would like to add this info to my article. Here's what I was told by each..
When I spoke with boat life they very clearly stated to me that a full cure of between five to seven days with Life Caulk is what they recommend before a launch. The tech support guy would not budge on this point even when I told him 3M 4200 and 5200 will finish curing under water. I could not get him to budge on this and he said tack and cure are two different things and cure times are very dependent on ambient temperature. He also stated that the air & hull temp can't drop below 40 degrees during the cure process and must be perfectly clean before application.
I spoke with Tom about 4200, 5200 and 101. He advised against 101 due to it's very long cure time in a short window situation or regular 5200.
As for 3M 4200 & 5200 Fast Cure he stated that while they will still cure under water they don't advise running the boat, as in water movement over the hull, until cure has been completed because it can erode any sort of fillet or seal thus causing a leak and possibly moisture entrapment. I think a slow motor to your dock would not hurt as he was mostly referencing power boat failures.
3M also stated that a 40 degree minimum of both hull and air temp should be adhered to and that the lower the temperature the longer the cure time. The hull must also be bone dry & free and clear of any paint
, dirt or oil when you are applying it.
3M's official policy on underwater use is to let them fully cure but this guy was being quite honest. He did say they have seen failures on quick launches that's why he advised NOT moving the boat after launch (no water flow across the hull).
Again, 3M's OFFICIAL LEGAL STATEMENT POLICY IS TO LET IT FULLY CURE BEFORE LAUNCH
. I say this because I don't want people running around saying 3M told me it's perfectly OK to launch in one hour even though it probably is if you're smart about it....