Bedding glass windows

[JT48348]

I agree it's cheap. But I also kind of like the simplicity of the system. The entire thing can be replaced at minimal cost and not much effort. Everything can be duplicated with low skill level. Having redone all my windows and had them in pieces I've developed a new found appreciation for the design.

Silicon is the solution for a sealant to bed the glass to the frame. The frame gets secured with a sealant that's more permanent and lasting like a 3m 4200 or boat life. I don't think butyl tape is the right tool for this job. It's place is elsewhere. Different tools different situations.

[rnummi]

A macro picture or two of the finished windows, how you bedded them front and back would be maaaavelous. Does the glass sit I'm a bed of silicone and is that all that holds it in? (Mine were out of the boat in pieces upon purchase). Question: What's the wood in the frames? Mine don't look like teak. Hypothetically, if one were to rebuild the frames... would you use Teak, Mahogany, Oak etc....

I have a molding carpenter that is refinishing the pieces parts for reassembly. The PO had cut starboard for the inner frames, I'm just going to rehab the old ones. Like JT, I think there is a certain New England character to the wood frames.

[JT48348]

Is there any update to this project?
Has anyone actually done it after all the discussion?

I'm starting my final winter project, which is reconstructing the pilothouse windows and re-bedding the glass. Just want to know if there's an update and see some photos.

Thanks

[rnummi]

JT, mine are still dry mounted (i.e. no sealant, just the inner frames holding them in place.). My sanding and epoxying of the frames worked out great. I saw (I think on Trawler Forum) where the "fix" to brightwork headaches was to coat with epoxy then use whatever you want as a finishing coat. So far, the epoxy is holding up perfectly. When I finish my new "hole in the hull" project I'll get around to rebedding. In the interim, they work fine, when it rains, a little seeping comes through but nothing significant. Definitely a project still on the burner. I did notice that butyl tape would actually "fit" around all four sides of the glass, i.e. start at one end put the edge of the glass in the middle of the thin butyl tape wrap the periphery and plug it into the frame..would probably work. The fact that the frame is epoxied will provide all the seal that is needed.

[rnummi]

BTB, I also had a light tint put on the inner face of each pane of the forward glass. I had previously noticed that Don's and my former neighbor's A27 each had perfectly clear widow panes.... Florida Sun is brutal so I opted for heat reflective 3m tint professionally applied before remounting the panes in their frames. Saves on the "trim" the tint step.

[Sprig1]

Rick that's a great idea on window tinting I'll have to check that out. JT I'm just about to put my glass in the frames. I bought sikaflex 295uv said it was good for glass. Ill probably use 4000uv on frames to pilot house. Sikaflex is probably bad by now bought it so long a go.

[JT48348]

After spending a weekend jerking with the pilothouse windows, I now have strong opinions on the topic. I rescind my previous statement that the pilothouse window design was a good idea. Yes it's simple and cheap, but it's stupid. Stupid way to seal a window.

My frames came apart relatively easily once I got them out of the pilothouse. The reason for this is because they are basically screwed together, one screw per corner like a picture frame, and the wood screws were rusted and broke in half. The head of the screw was on one part of frame and the shank was bedded in another. For every corner.

This means when you try to get the screws out you have to damage the wood because everything is coming apart due to rust or water damage.

Wait for it... you can imagine what happens when you try to put it back together. You can't get tight corners. I started by filling the holes with epoxy. But then redrilling the corners was less than perfect.

Meanwhile I cleaned up the glass panes. It's was a three step process: scrape the glass with a razor to remove 30 years worth of decals, glue, miscellaneous caulking, splatters and overspray of varnish and what have you; then wipe with acetone; and finally clean with water and bar keepers friend mixture.

[JT48348]

Right about this time I realized the wooden frames were actually too big for the glass panes. That's right, during dry fitting I came to the conclusion that the two forward pilothouse window frames were approximately 3/8" TOO BIG.

How can this be? Near as I can tell it's a factory thing. The panes of glass are original, safety glass, cut in a trapezoid shape. There are no right angles. But the frame has some right angles.

I tried one way, then the next, an infinite combo. But when I disassembled them I took detailed notes and labeled everything. I even drew a diagram to remind me how they went together. And they only go together one way. The frames from the factory were made too big.

I initially chaulked this up to wiggle room for thermal expansion or boat motion. But on studying the frames, they were 3/8" too big. Here's why: the lip that holds the glass is at most 5/16" wide. Which means even if the glass was floated in the center of the frame, there would only be about 1/8" of frame even touching the glass all the way around.

That's not enough.

So I decided if the frames were cut to size, then at least I'd have 5/16" of wood in contact with the glass all the way around.

[JT48348]

I hemmed and hawed for two days. I read up on thermal expansion and boat motion and window glazing. Then I gave up.

If you want your glass bedded in sealant, they have to be relatively tight in the frame. The frame fits into the cutout in the pilothouse and there's wiggle room there. But a loose glass pane barely touching a wooden frame is just stupid.

So I cut the frames down on one side, just a hair, to get a tighter fit and something I could bed the glass in.

And when I tried to screw it together, I realized it was even more of a disaster because 1) I cut mitter cutters like a drunk sailor, and 2) the corner screw technique is an abortion no matter how you fill the crew holes. This is 30 year old wood and it's tired.

About this time I went with the epoxy route, as previously suggested. I decided to epoxy the frame corners together. This accomplished several things: 1) it covered up my heinous mitter cuts and 2) made a stronger joint; and 3) sealed the corners for future water leaks.

[JT48348]

Here's what the epoxy job looks like on the side sliding window frames. When sanded and Cetol'd it's not that noticeable, I guess.

Soon as the two front windows are firm, I'll be bedding the glass with Dow 795 silicon. More to follow...

[Sprig1]

Glad you went first

[Ben423]

Just a note about epoxy. It does not hold up well in sunshine. Make sure whatever you coat the window frame with includes a strong UV inhibitor.

[JT48348]

The purpose of my epoxy is to join the frame corners like glue. Not for brightwork.

[rnummi]

Yep, looks just like mine. Only difference is I epoxied the whole dang frame. I mean, like decoupage.... had the same issues with screws. Hell of a way to run a boat yard. That being said... the windows now fit perfectly... no worries on the flexing frames. Also, (JT will cringe), I just didn't slap some silicone, 4000 or whatever, in there, as you recall, I had to move the whole boat to the water before the window project was complete. I wasn't about to slap silicone and run. So.... I have stainless steel bolts ala, Beckson holding my windows in.

[JT48348]

Photos of expoxied pilothouse windows. Now the glass fits tight in the sill and can take a nice bead of caulk.