adwuk
Active member
I use 3M 4200 and it works just fine. Not as adhesive as 5200, Sika 291 or CT1, which means you won’t damage the fibreglass should you ever wish to remove them.
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Sealant for through-hulls
- Thread starter RosieB
- Start date
ghostlymoron
Well-known member
I fitted an additional bilge pump on my Mirror Offshore and sealed the plastic skin fitting with PU40. I tightened up the backnut by hand and went to fetch my water pump pliers. By the time I got back, the PU40 had partially cured and I was unable to tighten it further but the seal was good so the 'nip it up after 24 hrs' technique wouldn't work and isn't necessary anyway. I've learnt that if you disturb the joint after its cured, you break the seal and it's likely to leak.