Bonding deck hardware vs. polysulfide caulk

[voice3]

I'm looking for options for re-bedding a stanchion base. On West System's website it recommends bonding deck hardware with thickened epoxy instead of using polysulfide caulk. They claim this is a stronger and longer lasting water tight seal. Has anyone used this method for a stanchion base? If so, did it work well?
Thanks,
Matt

[floatsome]

I use epoxy to build a flat base for deck hardware, not to seal the joint.

[baboon]

Epoxy will become rock hard, even when thickened. It will not give or flex and will eventually fail. When it does it may well pull the gellcoat off with it. Even if it lasts a while, you will have a very difficult time removing the parts in the future without damage. Good quality mechanicle fasteners and caulk or butyl tape is best.

[voice3]

Originally Posted by floatsome

I use epoxy to build a flat base for deck hardware, not to seal the joint.

Yes, I know about this method. But West Systems recommends reassembling the hardware while the epoxy is still wet, causing all the hardware to be bonded. I've never heard of this method before, and was wondering if anyone has tried it.

[arf145]

They really say that? And it's not even April 1. I don't get that at all. Reassembling hardware in wet epoxy? Sounds like a nightmare. Even assuming the result is watertight, it sounds like a forever sort of thing to me.

One nice thing about any flexible caulk is that should you ever want to remove the hardware, all you have to deal with is some bolt holes, the rest of the deck underneath will be unscathed. If I was shooting for something that I wanted forever, I'd look at 3M 5200 first.

But really, as baboon said caulk or butyl works well.

[sailingfool]

Originally Posted by voice3

I'm looking for options for re-bedding a stanchion base. On West System's website it recommends bonding deck hardware with thickened epoxy instead of using polysulfide caulk. They claim this is a stronger and longer lasting water tight seal. Has anyone used this method for a stanchion base? If so, did it work well?
Thanks,
Matt

Whatever you read on the west Systems site you must be mis-remembering, it would be pure foolishness to epoxy hardware to a deck. Epoxy is not a sealant.

[voice3]

Originally Posted by sailingfool

Whatever you read on the west Systems site you must be mis-remembering, it would be pure foolishness to epoxy hardware to a deck. Epoxy is not a sealant.

Here's the website:
WEST SYSTEM | Use Guides - Bonding Hardware

[poopdeckpappy]

I don't think you want to be Bonding your hardware, you want it bedded really well

Bonding would almost guarrentee you'll be drilling out screws and removing a layer of glass should you ever want to replace some deck hdwr


Unless it's a epoxy based polysulfide caulk, that is a strong bond, but it is still a bedding not a bonding

[billyruffn]

I second the comments about the bedding compound needing to be flexible so you keep the water out.

A tip for applying it: Apply the bedding compound to the areas as needed. In addition to the exterior edges of the fitting, I always put a circle of bedding compound around each of the fastner holes as well. Putting a little compound around the head of the fastner and on the inside surface of the washer won't hurt either.

With all the compound applied put the fitting in place and run the nuts onto the fastners getting them firmly in place but not as tight as you want then finally. Clean up the excess compound with an appropriate solvent and let the compound set up. By not tightening the fastners all the way down you won't squeeze all the compound out of the spaces between the fitting and the deck. Once the compound has set up, you can come back and torque the nuts down hard. With the compound set up, this second tightening compresses the compound and results in a better seal.

[mitiempo]

A good idea is to drill a countersink in the glass for each bolt so that there is an "o-ring" around each bolt head. Do not use 5200 because this will pull off
gelcoat when (not if) the hardware is removed. 4200 is better, butly tape is the best in my opinion. Tighten the bolts once, as if you do it a second time, you can break the sealant bond. Step by step with pictures on Mainesail's site. If the deck is cored, be sure to pot the deck with epoxy to avoid future rot in the core. Extreme stickiness of 5200 is not needed, but ability of sealant to elongate as hardware moves is , and probably stanchions move more than most hardware.