Rebedding in the rain?

[poopdeckpappy]

Not to get into a pissing match over caulking, but nowhere did the OP mention anything about plastic, I assumed when he said bedding he was referring to hardware bedding.

So unless his boat was built bt Revell, plastic is kind of a non issue

[gc1111]

Originally Posted by Maine Sail

Please try to be more careful in what you say or type as some might actually believe what you say and ruin an expensive part. Please check your "facts" before you post them!

Overview of Life-Calk Caulk Sealant - White, 2.8 OZ.

From the WM Site

"Versitile adhesive sealantOne-part, thiokol-based polysulfide sealant cures to a positive waterproof seal. Resists oil, brine, gas, water and most chemicals. Bonds to wood, fiberglass, metal and glass. No priming required except on oily woods such as teak.

• Formulation: One-part polysulfide caulking/sealant
• Recommended Usage: Fiberglass, wood, metal, glass; above and below water
• Material Incompatibilities: Not recommended; glass to vinyl, ABS/Lexan, plastic hardware to fiberglass/wood
• Adhesion Rating: Tensile: 80 psi; ultimate elongation 200%
• Cure Time: Tack free: 24 hrs; complete cure: 10 to 20 days
• Cleanup: Life-Calk Solvent, Model 139592
• Removal: Mechanical remova"

I have used Lifecaulk since the 70's as a bedding compound on fiberglass (i.e. plastic) sailboats. It works and works well. A blanket condemnation of using it on plastic is inappropriate. If it dissolved plastic, my hull would have more holes than could be counted. Maybe you should read your own posts as you make them.

[poopdeckpappy]

Also there are numerous polysulfied adhesive/sealants out there that ARE compatible with plastic, they are far better than anything mentioned here, just not as simple for the average weekend warrior to use for the quick fix or bedding

I know of one off the top of my head that is not only very flexible, it has a bonding strength of 1000psi

[Maine Sail]

Originally Posted by gc1111

I have used Lifecaulk since the 70's as a bedding compound on fiberglass (i.e. plastic) sailboats. It works and works well.

Me too only my personal choice is 3M 101 Polysulfide but it is one of my favorite bedding compounds other than butyl. I just don't use it on most plastics except fiberglass. I watched a guy destroy a brand new set of acrylic dead lights using Life-Calk a few years ago and he's spent over $600.00 to have them made. The polysulfide literally melted the ports overnight..

Originally Posted by gc1111

A blanket condemnation of using it on plastic is inappropriate.

Here's exactly what I said:

Originally Posted by Maine Sail

I agree 3M 101 is a better & thicker polysulfide and it handles UV better. As dog said DO NOT use polysulfide on plastics unless you know for certain it's compatible!

Here's What Dog said:

Originally Posted by sailingdog

Just be aware that you shouldn't use POLYSULFIDE sealants with plastics, as they're generally not compatible. POLYSULFIDE sealants will attack most plastics. BoatLife LifeCaulk is a polysulfide sealant.

As I read it, there is/was NO "blanket condemnation" made by either of us and we both clarified that it is not ALL plastics.

Originally Posted by gc1111

If it dissolved plastic, my hull would have more holes than could be counted. Maybe you should read your own posts as you make them.

Um perhaps you should read more carefully? See above..

In the US most don't refer to fiberglass as plastic in the general sense but rather fiberglass. While it technically is a plastic it is not one that is attacked by polysulfides. There are others that are not too. If you read what I wrote above it is clear that it was a qualified statement not a "blanket statement"!

Some plastics such as some formulations of Lexan, acrylics, PVC etc. may not be compatible with polysulfides. Polysulfides are safe for many plastics but not some of the typical plastic deck fittings, portlights etc.. they are perfectly safe for fiberglass and even some plastics used for through hulls.

Polysulfides are safe for use on GRP/fiberglass but not some other plastics!!

[Maine Sail]

Originally Posted by poopdeckpappy

Also there are numerous polysulfied adhesive/sealants out there that ARE compatible with plastic, they are far better than anything mentioned here, just not as simple for the average weekend warrior to use for the quick fix or bedding

I know of one off the top of my head that is not only very flexible, it has a bonding strength of 1000psi

Please lets not confuse Thiokol based Polysulfides with Polyurethanes!!! First polysulfides are not generally considered in the "adhesive sealant" category and secondly there is no commercially available polysulfide product that comes even close to 1000 PSI.

Life-Calk is rated at about 80PSI and 3M 101 has a tensile strength of 139 PSI and an elongation before break of 416%.

Polyurethanes =
3M 5200
3M 5200 Fast Cure
3M 4200

Boatlife Life-Seal (A Polyurethane / Silicone hybrid)

Sikaflex 295UV
Sikaflex 291
Sikaflex 291 LOT
Sikaflex 292
Sikaflex 252
Sikaflex 227 Fast Cure
Sikaflex 201US

Polysulfides =

3M 101
Boatlife Life-Calk

Polyether =
3M 4000UV

[xort]

Comments on Boatlife Life Seal???

[Maine Sail]

Originally Posted by xort

Comments on Boatlife Life Seal???

Use it carefully & sparingly as it contains silicone. While silicone does have it's specific uses on a boat I would steer clear of it.

I have seen chain plates that required re-bedding every few months because an owner at one point use silicone. The subsequent re-beddings would not hold and stick to the glass because it had been contaminated with silicone.

Once we thoroughly sanded the surfaces of both chain plate and the fiberglass we finally got a sealant to adhere.

Here's my own personal story on silicone and it's only part of why I avoid it like the plague.


In 1995 I purchased two Current Designs Solstice Kevlar sea kayaks. These were beautifully crafted vacuum bagged 18' boats that weighed about 45 pounds. I paid BIG money for these boats and loved them. Well after a few trips I was noticing water in the aft water tight compartment where your gear is stowed.

Kayaks are made in two pieces the deck and the hull then glassed together in a tricky process. To make a long story short I met the factory rep at one of my local retailers and we dunked the sterns of the kayaks into the demo pond vertically. I stuck my head in the aft compartment and there were about a dozen pin hole leaks squirting water into the boat along the seam. Both of my 3k boats were inflicted with this problem! The rep told me how to attempt a fix and I did with NO luck. I even went to a body shop supplier and got a special "silicone remover" that also did NADA.

After my unsuccessful attempt at repair we sent them back to the manufacturer for repair during the middle of the summer. After about four weeks I got a call from the rep that the boats were un-repairable. Current Designs built me brand new boats and shipped them to me.

How did this happen? The story I was told is that a "motor head" who worked in the glass shop was using silicone tire gel on his lunch break to detail his tires on his car and after lunch contaminated a number of boats during the hull to deck assembly.

The moral of this story is that in my situation neither myself nor the manufacturer could fix this problem even with judicious sanding and the use of very dangerous chemicals. NOTHING would remove this silicone and prevent the fish eyes. Current Designs ate 6k worth of kayaks due to the carelessness of one employee. I don't know how many other boats were totaled but I'm sure it was more than just mine..

Silicone has very few legitimate uses on boats and generally is NOT allowed on board mine unless it is a very, very specific use.... The stuff is like nuclear waste (Nu-clee-er not Nuk-U-Lur) in that it's nearly permanent.

Life-Seal contains Silicone.

[GBurton]

Never said it was OK - just pointing out that polysulphide will just discolor plastic, not cause it to melt or disintegrate.

Originally Posted by sailingdog

GBurton-

I am curious why you think it is okay to use Polysulfide sealants with plastics when even BoatLife says that LifeCalk shouldn't be used with plastics...

[GBurton]

The red square was because I was dumb enough to take some bait that a few members trolled.

On the Don Casey thing: I don't presume to know more than him about Polysulphide ....I was just posting my experience. I have not used it on plexiglass or lexan.....but I have some handy and I'm going to apply some boatlife polysulphide to it and see what happens

Originally Posted by Maine Sail

My boat was built at the factory using butyl. It's the only boat I've never owned where almost 85% of the fittings are still original and have not needed re-bedding. Even the hull to deck joint is butyl as well as the aluminum toe rails. The boat does not leak one drop..

Here's a 30 year old genoa cleat that I removed look at the elasticity!

And the 30 year old BONE DRY core..


These days I use butyl for just about everything..

P.S. GBurton has a "red square" for reputation for a reason.
Talk to the folks at Beckson, the port light company, and they will tell you EXACTLY what Dog said. Polysulfides will ATTACK and make many plastics brittle. It does a LOT more than just turn it yellow!!

Oh, and the venerable Don Casey apparently knos less than Mr. Gburton too:

Don Casey Article on Sealants (LINK)

Here's a direct quote from Don Casey on polysulfides and plastics:

"However, the solvents in polysulfide sealant attack some plastics, causing them to harden and split. Specifically, you must not use polysulfide to bed plastic windshields or plastic portlights--either acrylic (Plexiglas) or polycarbonate (Lexan). Don't use it to bed plastic deck fittings either, including plastic portlight frames. Plastic marine fittings are typically ABS or PVC, and polysulfide will attack both."

[catamount]

Originally Posted by xort

Comments on Boatlife Life Seal???

I have used Boatlife Life Seal with much success on my boat, and haven't (yet) experienced any of the drawbacks that others (such as Maine Sail) attribute to silicones. That said, I really only use it for plastics that are not compatible with polysulfides (Beckson ports, Spinlock clutches, etc...); I use Boatlife Life Calk (which is a polysulfide) for everything else.