Mast foot caulk type

Jun 19, 2021
6
Newport 17 Cherry Hill
Replacing my mast foot, previously had what seemed like regular silicon bathroom caulk between the hull and the foot.

Any material specifically I should be using? I figured something with some give to it.
 
Sep 25, 2008
7,092
Alden 50 Sarasota, Florida
Sorry, can’t help but I am curious - why would it be necessary to caulk “between the foot and the hull”?
 

Tedd

.
Jul 25, 2013
745
TES 246 Versus near Vancouver, BC
I've had mine on and off a couple of times. I use 3M 5200 marine sealant and it seems to work perfectly. You'll need a little heat to get it off next time but, in the meantime, it's bullet proof.

Make sure you seal the tube well when you're done. It's expensive and you don't want it to dry out!
 
Sep 25, 2008
7,092
Alden 50 Sarasota, Florida
The foot is bolted onto the top of my cabin, just to eliminate moisture from getting in there
Thanks for the clarification. You confused me with the "hull" description of where the mast foot rests.
But that begs another question - why caulk at the mast step on deck? Wouldn't that serve only to trap precipitation into the mast preventing it from draining? And if you have an wires (coax or electrical) through the mast step, doesn't that exacerbate any leaks at the mast step into the boat?
 
Jun 19, 2021
6
Newport 17 Cherry Hill
Thanks for the clarification. You confused me with the "hull" description of where the mast foot rests.
But that begs another question - why caulk at the mast step on deck? Wouldn't that serve only to trap precipitation into the mast preventing it from draining? And if you have an wires (coax or electrical) through the mast step, doesn't that exacerbate any leaks at the mast step into the boat?
I'm pretty green when it comes to sailing verbiage, my newport 17 is about as bare bones as they come so no fancy wiring in place for anything like that. I assume mast feet are all pretty similar, the bottom portion of the bracket is bolted and caulked to prevent anything coming in through into the cabin, the top portion that connects to the bottom of the mast is just bolted.
 
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Sep 24, 2018
2,579
O'Day 25 Chicago
Use Bed-it instead of 4200/5200. It's faster, better and requires almost no cleaning the next time you have to remove the mast base
 
Jun 19, 2021
6
Newport 17 Cherry Hill
I've had mine on and off a couple of times. I use 3M 5200 marine sealant and it seems to work perfectly. You'll need a little heat to get it off next time but, in the meantime, it's bullet proof.

Make sure you seal the tube well when you're done. It's expensive and you don't want it to dry out!
Yo
 
Sep 24, 2018
2,579
O'Day 25 Chicago
There's a reason it's been nicknamed devils snot. Getting it off can be a royal pain. The only place I'd recommend using it is a hull to keel joint and a hull to deck joint. Butyl also last longer
 

LloydB

.
Jan 15, 2006
817
Macgregor 22 Silverton
I agree with @kloudie1 Main Sail's butyl sealant is the best way to go for attaching deck hardware. I stored my Mac with the cabin and tabernacle covered in the fall and by January there was enough water in the bottom of the boat it was as if I had left the pop top open. I took everything that was screwed to the deck off and cleaned the surface and made my little butyl donut around the hole before I replaced the hardware. Not a drip since and I am confident that I can take that hardware back off and either replace it with new or put it back on without damaging the gelcoat or having to repair it.