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jackangier
12-30-2008, 10:01 AM
Please, I would like suggestions for material and process around new caulking for the forward facing windows in the main cabin. They take a pounding in weather, five windows approximately 18"x24", set in teak, and they are starting to leak a bit. I am also changing the bright finish to oil-based (Deks Olje) at the same time.

As I understand this forum enjoys before and after pictures, I am attaching links to my latest repair...rennovation of four forward cabin trunk portholes. These were corroded cast aluminum with SS machine screws, flanges bedded with 5200...a nasty piece of work.

Before: http://cid-3cfa77c4cc33cf5a.skydrive.live.com/self.aspx/Forward%20Portholes/Porthole%20Before.jpg

After: http://cid-3cfa77c4cc33cf5a.skydrive.live.com/self.aspx/Forward%20Portholes/Porthole%20After.jpg

As an aside, one of the wingnuts on these portholes has gone missing and I would appreciate any further suggestions on where to find one. Standard 3/8" thread, but oversized/heavy nickel plated over bronze with a spread of 2" across the 'ears'.

Thoughts?

-Jack

Concordia...41
12-30-2008, 10:53 AM
Someone will be along in a bit to offer real advice, but I just wanted to say HUGE DIFFERENCE in the before & after pictures!

- M

Lew Barrett
12-30-2008, 11:26 AM
The process depends on the construction style and how much work you are prepared to go through.

The portholes look nice, a good effort! Actually pictures of the windows would be just as helpful.

In the meantime, there are two basic approaches.

1. The quick fix. Here a caulking/glazing compound of some sort, and it doesn't have to be a marine product, is applied to the glass and over the exterior wood, just as you would imagine it be done, in an effort to keep the water out. This can be unsightly and doesn't always work well, or doesn't work well for long.
When done with some delicacy, you can use a product like clear Polyseamseal, work it in, and just before it goes of, clean up any extra residue with water. You are usually trying to seal minute fissures, so a careful application can work. Do not use a silicone product. Counter-intuitively, sometimes sealing the glass from the inside is more effective than sealing from the outside. Usually, it's a good idea to run product into both places. The reason is that boat windows are set in rabits, and rely on the fit of the glass to the wood. Sealing just at the edge can be problematic, as any leak anywhere along the perimeter results in water pooling along the bottom of the window.

The challenge with this approach is that boat windows (deadlights) are not constructed like house windows. They are leaking because the bedding/"glazing" compound into which they are set is no longer effective. The glass really needs to be sealed from the inside, so no amount of external caulking will work for long. Unlike house windows which are glazed, wooden boat windows are set in bedding compound.

Which brings us to method number 2; the hard way but more permanent repair.

In this approach the moulding surrounding the light is removed entirely and the glass re-bed. This is odious because it can be invasive depending on how the stops are fastened and finished. Be especially careful in removing the corner pieces, as those take the most time and effort to re-manufacture. After removing the stopping,
re-bed the window in the product of your choice. This will be cause for further discussion, but I have had lousy luck with oil based bedding compounds for this job, having had failures in disappointingly short order, say three years or so. The oil based compounds dry out rapidly in this application, so it is one where you might like to consider your choices. I have had good luck with Sikaflex 291 but a caution in using it is that it is a more tenacious adhesive than other forms of window glazing. On the other hand, my windows sealed with it have not leaked for many years.
As I said, this aspect of the repair, selecting the bedding compound, will draw the most fire and commentary.

Good luck! Leaking windows are a pain to chase down, which is why so many old boats have them. However, and equally, what is more gratifying than a tight boat? Rebedding your "windows" can qualify as a major project. But if you only have a few, it shouldn't be too bad.

ron ll
12-30-2008, 11:54 AM
As an aside, one of the wingnuts on these portholes has gone missing and I would appreciate any further suggestions on where to find one.

If I don't say it, someone else surely will. Wingnuts of all shapes and sizes can be found here in the WBF Bilge. :)

Lew Barrett
12-30-2008, 02:17 PM
If I don't say it, someone else surely will. Wingnuts of all shapes and sizes can be found here in the WBF Bilge. :)

Left hand or right hand thread? :)

Bob Cleek
12-30-2008, 05:06 PM
For my money, the best bedding compound for windows set in wooden frames is plain old (decent quality) silicone sealant... the stuff they make for bathtubs and so on. This is NOT UV resistant and you can't paint over it for beans, but your trim pieces moot those issues. Just don't get it all over the place when you use it. Use Dolphinite or similar for bedding the trim over it all after the silicone has dried. There should be a good margin between the edges of the glass and the wood side, so that when the wood swells, it will not break the safety glass, which can be cut to size from your pattern at any auto glass shop. (Don't ask me how I know this.) Just fill the space where the glass lays on the wood and between the wood and the glass edge with silicone and fair smooth to level with the face of the glass. Silicone is very flexible and will compress easily. I've done this for a long time and those jobs have never failed. Beware using any sort of bedding compound that can harden over time. Once it hardens, and the wood swells, your glass breaks (or maybe your plastic windows just pop out.)

Lew Barrett
12-30-2008, 06:23 PM
I'd disagree regarding the use of Dolphinite for any window repair you don't plan on re-bedding in the next three years. Dolphinite looses it's oils with disappointing speed in this application, and it's hard to make the small moldings used on windows hold a good seal using the usual tricks. The problem with this repair going off isn't that it's necessarily so hard to do the woodwork (if you keep the corners intact) but that it plays hell on any cabin finishes, and is especially annoying if you have a varnished house.

There's no question that silicone sealers are effective at keeping water out. The issue with them is that areas that come in contact with it are rendered difficult, if not impossible to re-coat with finish. That's the reason for my caution regarding it's use. If you feel you can bed your glass in it without squeeze out onto adjoining areas, by all means give it a try. I am not so sanguine about that because I've had trouble with silicone in the past. However, I'd agree with Bob that it's other qualities seem to make it ideal. So, if you can be neat and fastidious with it, it could be worth a try, but it's not a product I'd use in contact with varnish.

As indicated, the issue of sealing compounds is the one that will cause the most discussion. This is a question where the answer is determined by the prior experiences of the owner. I'd spend my time researching the product you choose to use with care. The rest is pretty much by rote. It's not uncommon for this area of selection to be vigorously argued over in these pages.

jackangier
01-02-2009, 11:55 AM
Lew, Bob,

Thank you for the very helpful input, I am sure that I will have to figure out materials carefully.

To your request Lew, I have attached the following album of showing some details of the lights in question, including house context (it is varnish and damaged), some epoxy repair in the corners when this issue was partially mitigated some years ago (provious owner), and some external shots of the weathered frames.

http://cid-3cfa77c4cc33cf5a.skydrive.live.com/browse.aspx/Deadlights

I am leaning to the more invasive solution, bedding in with pure silicone, tape off the teak, which (I think) should be fully saturated with oil before the glass is re-bedded. Thoughts?

jackangier
01-02-2009, 12:11 PM
Unrelated query - between the broken portholes and leaking deadlights, there are many (small) areas of damage to the interior woodwork on the boat. The layout is mostly 4-mm Bruynzeel Teak over Marine Mahogany, with both solid Teak and Honduran Mahogany frames on gangway rails, closet fames, etc.

I am loathe to strip undamaged surfaces, are there techniques to restore damaged wood without stripping it all down?

http://cid-3cfa77c4cc33cf5a.skydrive.live.com/browse.aspx/Damaged%20Teak%20Interior

Thanks for any advice, I am not expert in varnish systems so all input is most welcome.

Peter Malcolm Jardine
01-02-2009, 12:19 PM
First, I tend to use multi use polysulfides for bedding real glass windows. I've have good luck with that... and yes, I tape them off etc.

Second, anything less that removing the glass, and rebedding like a new install is a waste of time. I have also replaced glass at that time since age had introduced scratches and sanding marks.

jackangier
01-02-2009, 12:32 PM
Seriously Ron, where could one find one of these...anyone?

http://cid-3cfa77c4cc33cf5a.skydrive.live.com/self.aspx/Wingnuts/3-8th%20x%202-inch%20Nickel%20on%20Bronze.jpg

Peter Malcolm Jardine
01-02-2009, 12:37 PM
Try emailing Atkins Hoyle. They may well have made that size of port with a standard 3/8 wing nut. Also, try Davis marine hardware, distributed/ available through R&W rope warehouse..

jackangier
01-02-2009, 03:42 PM
Thank you Peter. I checked Davis Marine and saved their catalog - it has many nice fixtures - but no appropriate wing nut. I also left an e-mail for Atkins-Hoyle.

There was another thread referencing 2 other suppliers, but no joy. Closest is a 1 1/2" width, which would work, but would not match the others...maybe a wholesale replacement is in the future.

Thank you.

Lew Barrett
01-02-2009, 05:38 PM
There was another thread referencing 2 other suppliers, but no joy. Closest is a 1 1/2" width, which would work, but would not match the others...maybe a wholesale replacement is in the future.

Thank you.

There you go,

Re the condition of your interior Mahogany. To my eye, it looks like the finish has eroded over time, and continued intrusion has caused wholesale local lifting of the grain coupled with local discoloration. If examination proves this to be so, you can bleach the affected areas using the usual approaches and then start by locally rebuilding varnish in the worn spots, ending with a couple of coats for the entire panel. That is, if you decide not to strip it all. This will result in a lighter area where the wood was bleached. Over time, the areas rend to blend together and the colors begin to become "one."
Or, you can call it patina. Wholesale interior stripping and refinishing of a larger boat is yet another daunting task. Whereas repairing the windows is frequently an all or nothing deal, this sort of scratching and patching when refinishing is often good enough to see you through until more drastic measures become necessary.

I may be reading the photos wrong, but it looks like a piece of exterior mahogany was added at some point (it's a vertical piece) along one window to give a bit of extra "stopping" to that light. Do you know the one I'm referencing? It could be just the way I'm reading the photo though.

It sounds like Peter and I have more or less come up with the same conclusions, by the way, and use the same general approach in respect to materials selection. No big surprise. We often do.

Electra
01-02-2009, 09:08 PM
Spartan Marine (www.spartanmarine.com) stocks a 3/8 inch SAE thread replacement bronze knob (Part No. K475) or bronze knob round (Part No. K480) which may do the trick.