Buytl Rubber for External Chain plates

[zboss]

I am contemplating using buytl rubber from Compass Marine for my external chain plates when I remount them, instead of sikaflex or similar.

Thoughts?

[rebel heart]

Unless I have a really good reason I generally do what everyone else does, because even if it's not the best idea the results are predictable.

[Strait Shooter]

I don't think butyl is recommended for underwater applications and external chainplates can be considered underwater (if you're doing it right anyway) equipment, but I digress.

Sitkaflex
Free advice and all that........

[sailcruiser]

Originally Posted by zboss

I am contemplating using buytl rubber from Compass Marine for my external chain plates when I remount them, instead of sikaflex or similar.

Thoughts?

I did with a good bead of caulk for good measure. As long as the fitting has a mechanical fastener above the waterline. (I don't like to sail sideways so my gunnels generally aren't buried. I'm in the reef early, reef often camp.). Be sure to seal the core if you have it. I found I used quite a bit stuffing it into the hole but its cheap enough not to sweat it. I think I have slightly oversized cut outs for my chain plates but can't say for certain. 1 season so far so too early to tell.
SC

[Ocean Girl]

Check out this very good post by Mainsail, it is on another forum.

[pbiJim]

I'm unclear about what you intend to do. Are you going to use a sheet of rubber to make a gasket? Or are you going to dip the parts in liquid rubber & wait for it to dry?

[zboss]

Originally Posted by pbiJim

I'm unclear about what you intend to do. Are you going to use a sheet of rubber to make a gasket? Or are you going to dip the parts in liquid rubber & wait for it to dry?

If I decided to go this direction, it would be the Butyl Rubber sold by MaineSail. My chain plates are externally bolted onto the hull.

The plan would be to do something like Step 5 on the previously mentioned Mainesail link, but with chain plates.

From the following link it looks like it would be compatible with sea water but interestingly, should not be used in locations where it may come in contact with Fuel, like on or near a fuel fill. (scroll down for 'butyl').

Rubber Compounds of O-Rings - Viton, Neoprene, EPDM, Nitrile

[roverhi]

Originally Posted by zboss

If I decided to go this direction, it would be the Butyl Rubber sold by MaineSail. My chain plates are externally bolted onto the hull.

The plan would be to do something like Step 5 on the previously mentioned Mainesail link, but with chain plates.

From the following link it looks like it would be compatible with sea water but interestingly, should not be used in locations where it may come in contact with Fuel, like on or near a fuel fill. (scroll down for 'butyl').

Rubber Compounds of O-Rings - Viton, Neoprene, EPDM, Nitrile

Should work great. Butyl is extremely elastic and should seal better in the long run. The only caution I'd have is to go back and tighten the bolts several times after installation. Butyl is pretty viscous stuff and will continue to squeeze out over a couple of days.

[Ocean Girl]

Originally Posted by roverhi

Should work great. Butyl is extremely elastic and should seal better in the long run. The only caution I'd have is to go back and tighten the bolts several times after installation. Butyl is pretty viscous stuff and will continue to squeeze out over a couple of days.

+1 on this.
I bed a 13 ft long deadlight with the 3M butyl tape. If I didn't trim the edges just right I would track butyl around the boat. The boat was in the Texas heat, the deadlight at an angle pointing towards the sky, so the butyl really heated up. I used black butyl, the very color Mainsail says not to use, and for good reason. My fix to this problem was to run a bead of uv stable caulk around the port. But I think if you do this right, and its not in a high traffic area, you will not have the issues I had. It was my first time working with the stuff.