Leaking ceiling screws & I need your recommendations.

[Northbeach]

Here is the short version. Late last winter I removed and refinished the teak rails on top of my cabin. I received many helpful responses here at Sailnet and I ended up taking several of your suggestions. The teak rails look wonderful, probably better than they did coming out of the factory 30+ years ago. That’s the great news.

Now for the bad, I was at the boat today and noticed moisture that has not been present in winters past. I have tracked it down to the screws that I used to reattach the teak rails. The screws that are allowing water intrusion are mounted from the inside of the cabin up through the ceiling and into the bottom of the teak rails that are outside & exposed. I don’t think any of them leaked before I took them off to refinish the rails. I used the same hardware to reattach them. And now about 40% of them are leaking.

Is there a way of stopping the water invasion, and all the damage that will cause, without permanently bonding the rails to the upper surface of the cabin? I’m sure this is a common problem and many of you have been down this road before. School’s in session and I’m taking notes. By the way the boat is a 24’ 1972 Cal T/4. I’m assuming that the cabin has a wood (plywood) core and is coated in fiberglass rather than being 100% fiberglass – does anybody know for sure?

Unfortunately I am leaving on a 5 day trip and will be away from the computer, so if I don’t respond immediately to your suggestions it isn’t because I’m unappreciative.

[SimonV]

Did you bed the rail where it contacts the, the cabin roof. If not you need to, and the simple way is to champher the screw hole under the rail then put a ring of 4200 or selastic in and around the hole. As you pull the rail down the champher will fill giving you a water tight seal.

[Northbeach]

Simon,

Sorry for my ignorance but what does "champher the screw hole" mean? Will the ring of 4200 glue the rail to the cabin top? When I took the teak off I did not see any evidence of there being anything there previously. Obviously my mistake.

[Maine Sail]

A chamfer is a term often used in place of or confused for countersinking. A chamfer is mostly done with a router bit to put a beveled, usually 45 degrees but it can be any angle, edge on a piece of wood such as an edge for a counter top. A countersink, on the other hand, sets a hole into the surface that a wood screws head will fit into to recess the screw below or flush with the surface. The resulting hole has a beveled edge but the tool to do it is called a countersink bit not a chamfer bit. Here is what a proper countersink bit looks like for an existing hole: http://www.rockler.com/product.cfm?p...er=countersink

You MUST properly bed or seal EVERY penetration in the deck and this includes hand rails! The problem is you did not use a marine grade sealant and now water IS in your deck and some is actually leaking down into the boat.

Yes a product like 3M 4200 WILL essentially glue your hand rails to the boat this is why I prefer to use a product with lower adhesive properties and like 3M 101 or one with greater flexibility (elongation at break of over 600%) and lower adhesive properties like Sikaflex 291. What ever you do DO NOT use 5200 no matter how hard the dope at the chandlery try's to sell it to you!! Also DO NOT use Silicone! Silicone is next to impossible to remove from any surface. In the future if you ever need to refinish your rails, or patch your deck, you will need to be so aggressive with the sander to remove the silicone that it will totally defeat the original purpose..

When you bed your hand rails it's a good idea to slightly counter sink each of the holes, on the deck side, to create an o-ring effect. By countersinking each of the screw holes you'll have a nice little bead of sealant around each screw that would be squeezed out had you not countersunk each hole.

If it were me, I'd remove the rails and dab some sealant over each hole for the winter. Leave the bottom of the hole open so any moisture in the decks core (your deck is cored with wood and wet deck wood is NOT good) has some potential of drying out!

[TrueBlue]

EDIT- simultaneouly posted with halekai36.

Let me get this straight - you removed the teak rails for refinishing, reattached them to your deck without using any sealant, and you're surprised to find water intrusion to the cabin spaces below?

With all due respect, any penetrations through a boat - regardless of deck & hull composition, require some form of caulk, gasket or sealant. Otherwise, capillary action will cause water to travel through even the most minute spaces. Your best course of action will be to remove the rails and follow Simon's process.

To champher means to form an angled bevel to the screw hole's outer perimeter. As was said, this ensures that an adequate amount of sealant will remain around the penetration when the two parts are mated and compressed.

Your deck is most likely cored (not solid fiberglass), either with plywood, balsa, or a form of synthetic substrate material. If wood, the water of course will eventually rot the deck's core - evidenced by a spongy deck.

To prevent this, ream out the perimeter of each hole and fill with an epoxy, such as the West System, prior to caulking and reattaching the rail components.

[Maine Sail]

A chamfer is not the proper term for countersinking! If we have beginners here, who need advice, we should try and use the proper terminology, when possible, especially when trying to describe what tools to use to achieve the end result! Yes a countersunk hole has an angled edge that could be considered chamfered or beveled, due to the angle, but the tools to achieve countersinking and chamfering are in fact different tools! In the traditional sense or definition of the word chamfer it's an angle on an edge or a flute or angled slot in wood and not a round hole with beveled edges.

So what happens when a novice DIY boater goes to the hardware store and says I need a chamfer bit cause some guys on the sailboat forum told me so??? Unfortunately he will get a most likely get router bit with a guide bearing that will not counter sink his holes!

Definitions:
A countersink is this: http://education.yahoo.com/reference...ry/countersink

A Chamfer is this:http://education.yahoo.com/reference.../entry/chamfer

The Bits:
This is a chamfer bit and it has a guide bearing: http://www.internationaltool.com/fre...mferbitset.htm

This is a counter sink and it does NOT have a guide bearing: http://www.rockler.com/product.cfm?p...er=countersink

[SEMIJim]

Hate to break it to you nit-pickers, but the act of modifying a screw hole so the fastener to be inserted therein will be countersunk is chamfering or beveling the edge

Jim

[Maine Sail]

So do we use a countersink bit or a chamfer bit to make this hole???

[SimonV]

Originally Posted by SEMIJim

Hate to break it to you nit-pickers, but the act of modifying a screw hole so the fastener to be inserted therein will be countersunk is chamfering or beveling the edge

Jim

Thank You Jim,

You have to remember I am Australian and we speak the Queens English. My trade is that of a Fitter and Turner, although not for the last 25 Years. Sorry for any inconvenience caused by my use of the correct terms.

Halekai36, this is the wording of the sight you posted. This is a counter sink and it does NOT have a guide bearing: http://www.rockler.com/product.cfm?p...er=countersink

"A versatile tool that saves you a whole lot of time! No tool makes chamfers more quickly in wood. Now you can make countersinks in three different sizes. The 1/2'' , 5/8'' and 3/4'' heads easily pop in and out."

[Maine Sail]

Please ignore our usual forum banter and just know that:

1)You should bevel, chamfer or countersink your holes slightly
2)You must use a marine sealant between the hand rail and deck
3)You should leave the screw out for a period of time to let the core dry out
4)Never install anything through the deck without properly bedding or sealing it