Building Logs

Window frames glassed

Posted by Paul

With the core pared back 50mm around each of the windows next task is glassing in the solid glass frames. I put down 8 layers of glass , one layer at a time, wet on wet and the frame is just under 5mm thick. Very solid. First step is to round cove the square edge where the balsa rises from the inside skin (the edge of the balsa to the outside skin is already rounded by a router curve). After the cove I used a small paint brush to coat the inside skin, the cove, the balsa and the outside skin with resin in order to help the first layer of glass attach cleanly and easily, this is super important and especially so on the exposed balsa. Bubbles must be avoided and eliminated before the next layer of glass goes on. Then each layer of glass went on. The first windows I did, the square middle front windows I did in one continuous layer of tape. Its quite difficult to get the glass to go around a 90 degree corner and stay smooth and flat and some of the corners on the next windows have corners that are greater than 90 degrees. So I decided it might be easier to do butt joins into each corner. So one tape extends straight on through the corner and the next tape starts butted up against that tape. You cannot overlap them in the corner otherwise over 8 layers the corners become 16 layers. The next layer the butt join would be on a different plane to the one below so that the butt join does not stack one on another. Kind of like laying bricks. The layer above is half a brick offset so the join between bricks happens above a full brick below and so on. Same with this. It was somewhat quicker to do, much neater in the corners. To be sure that the corners retained integrity I did 2 layers of butt join, a layer of single length tape all around, so spread through the corner in one long piece, then 2 layers butt joined then full length tape again then finally 2 more butt joined layers to make 8 in all and a final layer of peel ply. A consolidation roller between laying the next layer ensured no bubbles.

This long weekend has been super cold in the shed. It has been getting down to 2 degrees overnight!! And for the first time ever in the build I have been heating the resin before applying it. I didnt at first and the resin was very thick, I could feel it when stirring it and when applying it. My method for those that have forgotten is to lay a layer of plastic down on a table and using a scraper (like a blunt oversize chisel) I dip it into an icecream container of mixed resin and spread it out over the tape, for long tapes I pile it on over itself over the width of the table (about 1500mm) you only have 3 layers for a 3.6 meter tape. I then roll it up wet to transport to the job and roll it out again as I go around the window. When cold the resin takes longer to spread onto the dry tape, but you dont end up using more or less. I heated the resin for a second window (the side windows) and used exactly the same amount of resin for the other window of the same size but it went on much easier and I shaved half an hour off the time it took to do warm resin over cold. But it went off faster, so I had to move faster, so in the end I dont really know if I was working faster because the resin would go off faster or not. But being so cold, even after heating the resin would give me an hour window to work with it. I didn’t need it but knew I had it if I needed it. It took me 2 and a half hours to do the big windows cold and 2 hours with warmed resin. In the end I could have continued to work without ever having to have heated resin (I just had a small electric fan heater blowing on the 20 litre resin drum for about 10 minutes before mixing it), but I just wanted to see how much easier it might be. Not so much. All the window frames have now been glassed. All that is left is to trim them before fairing.


One other point worth mentioning. I ran out of 100mm tape a long time ago, I have just 150mm tape left now. Too narrow to cut tapes in half (they would only be 75mm each or if I cut 100mm off I have no use for 50mm tapes, I already have about 4 rolls of 50mm tape left and have no idea what 50mm tape would be used for anywhere on the build so far but they came in the kit for some reason) so I looked at buying more tape rolls. It turned out to be way cheaper to buy full width cloth (1300mm) and cutting 100mm tapes from it. So I did. It took me about 2 hours to cut 20 meters of full width 450g double bias into 100mm tapes but it saved me about $100. I figure I am worth more than $50 an hour, but unfortunately I now have the time, well not really as I really need to finish and get out of this rented shed,  but I definitely don’t have the spare cash. The boat cant tell the difference between self cut tapes or tapes that come cut to width on the roll. By the way, I didnt cut 2o meter tapes. I cut the full width roll to the length of each of the window tapes then cut those lengths into the 100mm (actually I staggered them from 120mm down to 100mm as I only needed 12 tapes of each length the 1300mm width allowed me to vary the tape widths and wanted the tape pancake to taper out onto the outside skin. Although it will be covered in bog and wont matter, its just easier to ensure there are no bubbles when it tapers out neatly onto the outside skin).



I spoke with a local plastic supplier. Polycarbonate is about 20% more expensive, stronger but more susceptible to scratching than acrylic and clear is about 20% cheaper than dark tint (black). The curved front saloon window will definitely need to go into the oven and be molded hot to the curve and it will set to it which will make it much easier to glue and seal into the boat, almost as easy as if it were a flat window. The bedroom curved window is long and not very tall so as a result may be able to be cold molded (stuck down at one end then tortured around into place) to shape although I would probably prefer they go into the oven too, its only $100 per window to have them heat molded and the front saloon windows are flat so they wont need any shaping and I will just tape and silicon seal them. That just leaves the side saloon windows that are about 90% flat but curve in at the top forward corners about 70mm over the last 400mm or so. So whilst the panel is mostly flat, the bit that curves in does so over a short distance even though it does not need to pull in far it might be difficult to pull in an 8mm thick window that far over just a short distance, so, it is most likely that this will need a little heat to help it bend and cure to shape but probably wont need to go into the oven.

For those that dont know, the method for attaching plastic windows these days is a layer of 5mm foam double sided tape is stuck to the  inside edge, (perhaps 5 or 10mm from that inside edge) of the space that the window mounts to, after the boat is painted of course. This double sided tape has 3 roles, firstly it holds the pane in place until the actual adhesive is applied and second it keeps the window about 5 mm clear of the boat so that the adhesive/sealant can fill the void and finally it acts as a dam for the sealant that will be squirted into the void under pressure with a silicon gun. The window must not be touching the boat. It needs at least 5mm clearance under and around it. The reason is it will expand in the sun and needs to be able to do so without being restricted by the edges of the boat. If it is, it will pop out or break the seal and leak. The sealant is designed to stretch with the window each day (the window will expand each day and contract back again over night then expand again). And the final touch is to cove the sealant with a nice concave sealant edge. Unlike the method used in the past, there are no through bolts holding the window on. Not only are the bolts somewhat less attractive, they have a tendency to leak, and the windows often cracked at the bolt holes. If done correctly the new method is more reliable and more attractive than the older method.

The other thing I am looking to do is to have clear windows with an added tint like a car tint, except on the outside of the windows. Silver tint reflects about 80% of the suns heat so unlike a black tinted window which is in the plastic itself this is in a film on the outside of the plastic and reflects the heat before it hits the plastic. This has 2 huge advantages, first and most obvious is that heat is reduced inside the boat. The black plastic not only absorbs more heat because of its color it radiates it into the boat like a bar heater. The reflective tint does not allow the window to get hot to touch on the inside of the window and as a result does not radiate heat into the boat, at least nowhere near as much. The other advantage is that plastic windows craze as a result of the effect of UV. By reflecting so much the plastic is protected and would take much much longer if they ever would craze. And finally, the reflective metallic film is more scratch resistant than either acrylic or polycarbonate is on its own. Although the clear is a little cheaper than the dark tint, the saving is taken again by the reflective film so cost is about the same as a result. But it is the heat solution I want to use. All up my windows should come to about $2500.

There is one small downside, not sure how much of a problem it might be, but the silver tint reflects toward the side with the most light. So during the day, the sun is reflected and the effect is like a mirror on the outside so you get privacy inside. All good. But at night the opposite is true, so instead of being able to see out, at night you have a mirror wrapped around the saloon. You cannot see out unless a light brighter than you have inside shines outside, and everyone can see in, if the lights are on. The moment you turn the lights off it reverts again. During a night passage you would not have any lights on, so wont be an issue underway at night, but may be an issue at anchor not being able to see boats approach. Having said that, many boats dont display any lights at night anyway and you can hear them but not see them, and of course if you are at anchor what are you going to be able to benefit from being able to see  lights outside at night (assuming them to be less light than the inside lights)? So its hard to say, I cant see any downside but you never know, it may not seem such a good idea once you have lived with it for a while.  It is very hard to argue against it on a cost benefit analysis.

One other thing has me quite chuffed at the moment. I made a small mistake with the placement of my roof that made a distinct change in the appearance of one part of the roofline. It has been worrying me for some time, whether it needed fixing, would it be obvious to others, etc. For some reason it did not seem to perturb Dean the boatbuilder that will be helping me fair my boat. I expressed my concern for the mistake a few times and he shrugged it off with “I’ve seen and fixed a lot worse”. The problem is entirely cosmetic and makes absolutely no structural difference whatsoever. Let me explain it. The wrap around panels in the turret are pre-cut kit parts. The main bulkhead with the doorway in it is also precut. (I know of 2 builders building the same design that modified this bulkhead by adding some width to it, this widens the cabin at the bulkhead and therefore narrows the side decks, but it makes entry to the hulls much easier if the steps are set aft near the bulkhead. I mention this to illustrate that there are many variables available but they do not effect the structural integrity of the boat).

I did not alter the main bulkhead. So as a result the height of my cabin roof is set by that bulkhead height so in that regard my build is no different to any other 1230/1250 Wilderness. What I did do by mistake, is set the roof about 40mm further forward than the plans specify. Because the wrap arounds are pre-cut so therefore a pre set size and it means in order to span the space between the underside of the pre made roof (not part of the kit other than you get mdf molds and instructions as to their spacing which sets the size and curve of the roof strip planking) and the deck which is also part of the kit, the angle that it would sit at is slightly steeper as a result of the front edge of the roof being further forward. So in other words my cabin raises from the deck at a slightly steeper front angle to other 1230’s. It is imperceptible but its there, my guess is it is no more than a couple of degrees difference at most. I guess if 2 of us were rafted up you might be able to pick up on it but I doubt even then most would notice it. The way the roof meets that front panel is supposed to be on a continuous plane changing from flat front into curved roof but because my front is at a slightly different angle to the original that join line is now also a point where there is a slight change in angle. This creates the impression of an “eyebrow”. Its only a very slight change in direction that can be faired out but had my front met my roof at the correct angle there would have been no need to fair there other than fairing out the tape line. If you look at the first pic below you can see the slight change in direction at the join line, the curve should start at the join if it were at the correct height which is lower and you can see this by looking at the middle pic, the roof chine is about 100mm above the window line down the sides of the cabin and stay there until about half way around the curve and then the line moves upwards away from the top of the window line. The window line is level set by a laser, the roof line should be too so should stay 100mm above the window line or about half way between the window line and the now roof line and the 3rd pic shows an mdf batten. It is touching the top of the window frame and also out of shot I am pushing it down to the roof at the top. In the middle it is just touching the “eyebrow”. So bog either side of the “eyebrow” should fill the gaps you see under the batten and would now be about 5mm at the deepest. The shadow that the batten creates makes it hard to see but the gap under the batten is 5mm.


And I guess theoretically, the cabin front being slightly steeper I might have a slightly poorer coefficient and therefore a theoretical windage disadvantage but because every boat is trimmed slightly differently (weight aboard and its distribution), performance difference as a result of this would be impossible to measure and even if it were, it would be infinitesimal. It certainly has never worried me, what had worried me was getting the appearance right.

OK so thats the downside of my mistake if you could call it a downside. More the fact I know its there and why (now…I didnt until many months later) more than anything specifically about it, but here is the neutral (neither good nor bad) part of the issue is that I have been concerned about how to or if to hide this issue. I nearly said defect but as you will read, it really isnt a defect. The visible manifestation is that the line where the angle changes from cabin side to roof does not wrap around the cabin on a level line like it does on other boats. It is level along each side, then the line heads upward about 100mm as it goes around the curve then levels off across the front. Its all very neat and looks good if that was the intention. And with some defects that are not problems unless we make them out to be you have 2 ways to deal with them. You either hide them or feature them. Hiding on the inside is super easy, in fact defect or no, it was always going to be hidden, under the liner. So on the outside I wanted my boat to look no different to other boats or if different looking not look out of place or odd. But for a while in my mind it seemed we might have to highlight the difference rather than go to the extra work of hiding it. Hiding it would require about 10mm of bog across the front of the cabin roof to fair out the hard line created by the eyebrow my uplifted front roof to cabin join line causes.

Until I glassed the window frames in. The extra 5mm of glass height that the window frames create has to be faired out by filling with bog and gradually sanding the angle back out in the same way you hide a fibreglass tape line down the hull sides (or anywhere else) by bogging either side of it and feathering it out to nothing. Except in this case the tape line edge is 5mm high. Well, with the 5mm added height, the depth of the bog required is only 5mm to fair out the “eyebrow” instead of the original 10mm. Imagine a high point in the form of a peak of 10mm but you want a continuous curve, you need to add bog either side of the peak and then sand it (fair it) to your curve radius. If you add 5mm of height to one side of the peak then your peak is only 5mm higher then the amount of bog required to hide the peak and end up with the curve is so much less. Perhaps Dean knew this all along and that is why he dismissed my concerns with little or no concern of his own.

Now every give has a take. Here is where my mistake is most fortuitous and why I have come to be thankful I made it. I have had many visitors to my build that are building their own boats. One of them is building the exact same boat. And every time he and many others visited they commented on how much bigger the inside of my boat felt in comparison to theirs or others they had seen.  I originally put this down to my furniture placement. I built my cockpit and saloon seating to hang out over the chamfer panel instead of fully on the bridgedeck. This robs space from the internal space in the hulls, but it adds 1 meter to the width of our cockpit and saloon as a result (500mm each side). We figured we would spend far more time living on the bridgedeck and only go into the hulls to sleep or use the bathroom so we felt we would rather have a bigger living space than hull space even though the narrower hull spaces is somewhat claustrophobic. The added living space was far more beneficial than the lost hall spaces in the hulls.

But I now believe there is more to it than that. My saloon roof is the same height as theirs at the rear bulkhead above the doorway, but whereas theirs slopes down from the bulkhead forward, mine is level (this is the mistake I made by setting the front edge a little higher as a result of the roof being a little forward). I set the roof as level thinking that is how it ought to be rather than as a measurement from front to rear and as a result mine does not slope down until the curve whereas everybody elses slopes down from the bulkhead and increases in that slope at the curve. It did not occur to me at the time that I was altering the cabin side line across the front of the cabin. I simply did not notice that line curve up.  The result is slightly less than 100mm or so but that extra head room above the saloon seat whilst not needed because it is at a point where you are seated so neither way results in you hitting your head, but the added space gives the impression of size, in the same way rooms with high ceilings feel larger than they otherwise would. And whilst there is no practical use or advantage of that space, perception is everything. If people feel like my boat is bigger then it is bigger, (even though it isnt), its just too many people that have first hand experience of the size of boats all making the same comment, its too many to be coincidence. Its just another example of falling ass backwards into a design improvement that I have a happy knack of with this build.

I thought it an interesting aspect of my psychology and I am sure that of other “amateur” builders regarding the perception of the seriousness of mistakes once they are discovered and the perceived difficulty of remedial action. Perhaps what made me more so or even un-necessarily concerned with this issue (it is no longer even thought of as a problem!) is that when I first noticed that my roofline was not quite right I engaged the advise of a boatbuilding expert (I wont mention his name but he is highly skilled and has a lot of very high profile boats to his name) that was working on Nine Lives (the other cat built in my shed) and he offered to work with me to fix it. But he certainly gave me the impression that the fixing was not a simple matter and that it was a good thing I had discussed it with him.  But to be fair to him, he never said any of that, I just imagined it, in the manner he discussed it with me. We spoke about building molds for the windows, making them off the boat then glassing them into the boat then fairing the boat to them once in, and before they went in, having the windows made to suit the molds. Life for anyone can change a lot in 2 years and about a year ago I visited the boatbuilder to start planning the work on my boat. We agreed on a rate and the approximate time it would take and he offered to start drawing window options for me.  That was the last I heard from him. I rang him a number of times and got his answering machine each time and left message after message. He has left some tools in my shed and in the end my last message was I accept you no longer wish to work for me, but do you want to come and get your tools, no hard feelings? I didnt get an answer to that either. Who knows what may have happened, he is a very nice bloke, I may never find out, which is a shame. I meet people that spoke to him just last week etc, but have not bumped into him or learnt why he did not want to talk to me. And I guess the longer it went the harder it got for him to ring. I get that. But his not answering me started in my mind a little of a panic. I had a problem that I created and then thought I had it solved only to lose that solution again, and the worst scenarios played out in my mind. Perhaps he thought the job was too hard, maybe it just cant be fixed (I even thought that perhaps the best solution might be to cut the roof off at exactly the level line and build it again)……demons start to niggle at you and you wonder if another solution will present itself.

The time came to do the windows and I asked Dean what I should do (remembering that I thought I had a huge problem and he did not) and he said all I have to do is just mark the windows where I want them (use a laser to get them level, not critical but will look better), cut them to the shape I want, remove the outside skin and decore 50mm and glass a frame into the opening. It is pretty much the way I am sure the original window were going to be done, (a solid glass frame) except the frame was built on the boat as opposed to being built off it and glassed in later. And the solution has been easy and revealed that there is nothing wrong with the roof that a little bit of bog wont fix (and bog is a solution to visible imperfections on just about every boat built to some degree or another, and 5mm of bog at its deepest is not considered a lot, we have a perception, there’s that word again, that bog is bad because of our experience of what it means on a car but it is quite normal on a boat, in fact it would be nearly impossible to fair a boat without it).

And apart from the advise on how to do it, I did it. Thats the point of this part of the blog. To try to demystify some of the problems encountered. I was never told that the job was in any way problematic. I built that up in my mind. The original boatbuilder didnt suggest that his solution was particularly expert or complex, I just imagined it to be, because I had decided in my mind that the mistake I made was catastrophic, whereas in reality it wasnt even a blip in some peoples thinking.

But when it came time to do it myself, I not only could but I did.

And what that does is add to your feeling of achievement. And I am feeling it! There are no problems that cannot be solved and there is little so wrong that you could do that cannot be fixed. And if you are lucky like I seem to be, some of those mistakes will actually end up enhancing your boat.

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1 Comment

  1. Henry

    I would be leery of placing a window film over your windows whether they be polycarbonate or acrylic. The film has a different expansion/contraction rate due to its thickness and material. On the boat I am restoring, the replaced hatch and ports I evaluated doing this. After much research I opted to get the “glass” pre-tinted. There may be a product especially made for the polycarbonate or acrylic, but I am not sure if there are any cost savings.

    Good to see you posting!

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