Windows

[Watto]

I’m trying my hardest to find a previous topic on window replacement. Someone even made templates and a silhouette edge to hide the trim.

Thoughts… links?

[Geoff]

Hey Watto,

Here's a few to check out...

viewtopic.php?f=4&t=339

viewtopic.php?f=2&t=1057&p=5770&hilit=windows#p5770

viewtopic.php?f=4&t=498

[Geoff]

I redid my windows last month.

#50 had the good old lavender perspex. They weren't screwed but riveted, 1/8" aluminium rivets. Bedded with clear silicone. I read in other forums you must never use rivets or silicone, but they never leaked a drop.

#111 had black perspex (technically dark grey I think) windows and the front hatch window too. It looked flash as and made poor old #50 look very dated. But they leaked. They were bedded in a rubber compound, Sika or similar. Whoever had done it had done a good job laying the Sika but only put a screw in the end of each window, so 2 screws per window. The perspex had sprung in a few places causing leaks. I suspect maybe whoever did it intended to put more screws in but didn't get around to it.

Because #111 had some screw holes drilled already, I decided to rebed with sika and drill the full complement of screws. But I followed Emrys advice for #50. I bought the vhb tape, and worked out that I needed 600 x 1200 mm of perspex. So I bought that in 6mm dark grey.

My procedure:

#111. Drilled through all the boat window frame screw holes into the perspex from the inside with an undersize drill. Put foam tape around the inside of the windows against the frame to block the Sika coming through later. Removed the windows. These had been fitted new about 10 years I think (gleaned from posts on the forum). As said, the Sika-like product has sprung in some places from the perspex as not screwed all round. But it was like concrete against the fibreglass. Took some work to get off.

While I had them off I traced them onto my new perspex sheet and cut them out with a jigsaw. The cutting was heaps easier than I expected. I also cut one for the fore hatch. Because it was shaped, convex, I measured with a dressmakers tape, traced the window, then pretty much freehanded the outline larger to match the measurements.

Then I drilled the clearance size holes in the windows. Drilled each hole in reverse to start to minimize chipping. Put masking tape around window frames on the boat, and also on the outer face of each window. Then laid a good bead of Sika between the foam and the edge of each window and screwed them in. Then filled in around each window with more Sika using my digital applicator. This was the worst part of the whole job. In spite of my masking still ended up getting bits on the fibreglass so had to keep going back over with turps.

#50. Drilled out the rivets, levered out the windows and cleaned off the silicone. The bond between the silicone and the fibreglass was nowhere near as strong as between the Sika and the fg on the other boat. From there, followed Emrys tutorial. Also applied a great tip from Mark who did Aminee's windows, with regard to lining them up. The most critical thing as is continually repeated with vhb application is that you have to line up right the first time. Marks suggestion of making a mark on boat and window at all 4 points - top, bottom and both ends, was a huge help.

Applied the vhb tape to the boat,

peeled the inside protective cover, lined up with help of second person watching 2 of the marks each, and pressed on. Applied pressure with a cloth all round.

Removed outer protective sheet and masked up boat and window. Applied Sika around the gap same as the other boat. Same s***tty job.

Re the window for the fore hatch. I thought the one on #111 looked trick. Before I drew my new one I tried the one from #111 laid over the place where it would go on #50. It fitted exactly, size, shape curves and all.#50 is single hinge, #111 is 2 hinge. But the window moulding is the same. So after I cut out my new one I shaped it with a heat gun so it would fit the curves and not try to pull away from the vhb tape. Then I cut out the hole with a jigsaw and fitted it up same as the side windows.

A few notes. The vhb tape method was much, much easier. If it is a superior bond as claimed then thats a real win-win.
Using Sika for bedding 1 tube was enough for the 4 side windows, but would not have been enough to also do the front one. Trimming the 5 windows on the vhb job used less than half a tube, so I had plenty. Just making the point that I wouldn't have got away with 1 tube for the full bedding and trimming of the 5 windows.

Nothing new here I don't think, but I got to use both methods side by side and compare. A week later we had 5 inches in 3 days and neither leaked a drop.

Timeless looks much younger with the black windows and hatch. Should be good for half a knot I reckon.

[Watto]

Hey Watto,

Here's a few to check out...

viewtopic.php?f=4&t=339

viewtopic.php?f=2&t=1057&p=5770&hilit=windows#p5770

viewtopic.php?f=4&t=498

Thanks. It was the haulout of spritzig.

[Ozzie]

Comprehensive tutorial Geoff and good heads up on the heating of the front window to get the shape. I still have to redo my front. As a mentioned when I did it the first time I put substantial screws in each end to hold the shape and lesser screws in the surrounding areas. This ultimately created small stress cracks in the Perspex and looks crook, even though it has not leaked yet. If going again I’d use the tape.

Funny the post on the cost of the tape in response to the question I asked is gone. Anyone remember the details.

[Ozzie]

Ok, found costs mentioned in Emrys’ post but there was another, more recent costing that’s gone .

[Watto]

. I bought the vhb tape, and worked out that I needed 600 x 1200 mm of perspex. So I bought that in 6mm dark grey.

Got a pic of how it looks?

I was thinking of using the clear vhb, under a dark grey Perspex. My windows are over 2m long(single piece covering multiple windows).

[Geoff]

Hey Ozzie, this is my order off ebay.

https://www.ebay.com.au/itm/112056908803

Bit less than $65 delivered.16.5 m, which is more than needed.

If you heat and shape the fore hatch window you have to remove the protective cover both sides. Apparently if you don't it becomes very hard to get off.

It took longer to make the window than it did all 4 others. Bending and rebending, then sanding down around the edge to make it fit properly. Orbital sander made shaping the edge easy. I stuck bits of masking tape near where it needed to be sanded while testing. Once you get it out and back to the bench you have no idea.

When bending under heat, some things are obvious after you have done them but would have made it easier if done the right way.

It bends easily in the middle and you think because that is where the greatest curvature is that's where you start. But getting some curve in the edges is much harder. I would try to get some bend in the outer 30mm periphery first. You need to clamp it in something to get leverage at the outer edge, like a vice in rag or similar.

Also, its easy to bend across the vertical (short) axis so do it last. I didn't.

[Geoff]

Pictures in post now.

[Peter T]

I have my windows out at the moment in readiness to paint cabin and topsides. Iwill then be replacing them.
I could trace them on to paper for anyone if they want. Cheers