Super Snoopy 050 9:05pm, 14 April 2008
That's it - I've had enough of trying to bond flapping bits of perspex with black gunge, just to get the moody one piece window, super yacht look! My latest iteration has been as much of a disaster as the previous two and the only way I can keep the water out is to slather clear silicone onto the upper edge of the windows. They now have the well vaselined look of a boxer's eyebrows or a prop forward's ears! I'm getting separate aluminium framed windows as quickly as I can.

The sages at the club mutter things about flexing when afloat as opposed to being on land and when I take to the ground twice a day, I guess there will be a lot of flexing.

Two questions for the group.

1 Can anyone recommend a reasonably priced supplier of aluminium framed windows?

2 Are the window holes in the GRP the same on all A24's?
PembsA24 11 years ago
I've heard redoing the one piece window can be a bit of a nightmare. Ours needs doing, it's been leaking for a couple of years, we keep putting it off! I've seen a topic detailing replacing them on the other Achilles website. Did you put completly new windows on or reseat the existing ones?
Skykomish E29 11 years ago
it will be interesting to see if Ron has similar problems as he is securing his without screws.
I would have thought a continuous bead of siklaflex around the whole frame would have been enough. I won't insult your intelligence by asking if you ensured that the surface was level and clean.
And you are not still using Polycarbonate for the windows?
I am not sure aluminium framed windows are going to do the trick either judging by the amount of sealant I have seen around the boats in the marina, you are still going to have the sealing problem against the frame and side of boat.

The holes for the windows theoretically are the same but there are bound to be slight differences due to variances in manufacture. I assume you mean window cutouts and not screw holes.
Tocviria 11 years ago
What is the difference Polycarbonate, Perspex, Plexiglass, extruded or melt? I have been wanting more definitive windows since I own the 840. I think I will try the glued with SIKA 295 and the primers.It looks a big job.Ihave 6 windows ,where the 24 and 9 have less. Ithink only 2? The glue is warrantied for 25 years is approved by main classifiers, and it is immensely strong.
NormanKlipspringer 11 years ago
I have rebedded my windows twice with Silcaflex and they still leaked. I have now had a friend (ex window fitter) put (as a temporary fix) a bead of clear silicon around the top edge and sides of the windows. This seems to be working. The difference is that he used LOW MODULUS silicon and not Silcaflex. The LM means that it is much more elastic and will not break away under flexing as I suspect the Silkaflex does. When I have the time I will take all the windows off and bed them again using LM silicon. The previous discussion on this topic refered to a specialist company who used a special silicon, which I suspect is also LM.
rothwell_neil 11 years ago
Window in Emily was put back with clear silicon bead all round the outside by previous owner. He told me that he had been told to use this by the boat yard as they never managed to get the whole window sikaflexed before it started to go off. As the window was the only part of Emily that didn't leak when we got her it seems to work well although doesn't look too nice close up.
Skykomish E29 Posted 11 years ago. Edited by Skykomish E29 (member) 11 years ago
Antonio : Polycarbonate expands and contracts dramatically whith temperature changes, something I found out whilst diving in Greece with a Polycarbonate Video housing, The casing was left in the sun on the dive boat on the way out to the site , on entry to the water the seal leaked causing ingress of water until it had cooled down. This is why conservatories have a tendancy to leak, as the roof is usually Polycarbonate sheet.

Perspex is I believe a brand name for Acrylic sheet which according to a friend of mine comes in different qualities depending on usage some have a "rubber" content that makes them more felxible but suseptible to scratching (as it is softer), this I used on the windshield of a motor boat that i restored and was able to curve the ends 90 degrees without preheating.
I know Ron will disagree about the use of Siklaflex on windows but i know that PBO did a bit on changing windows and they advised against siklaflex and suggested silicone. I only hope we come up with a definitive answer soon as I need to replace the windows on Aeolus
Tocviria 11 years ago
I resealed with Sikaflex, but it did not last more than 5 or 6 months. Then I resealed with silicone and it lasted more than year. The Polymax flexible glue the same as Sikaflex 295 claim 25 years of life and UV. I do not now if I will last other 25 years but 4 oryears would be enough for me Tocviria
Daddsie 11 years ago
I replaced Rumrunners one piece with acrylic last year. I used stainless round headed bolts and nuts 4mm if I recall, and hid them with u shaped trim internally.

As for sealant I used an all weather clear, flexible mastic that can be applied in the wet.
Super Snoopy 050 Posted 11 years ago. Edited by Super Snoopy 050 (member) 11 years ago
I replaced the port side window initially because it was heavily crazed and cracked. This was held on with Butler's original black stuff and self tapping screws.

Attempt one was with polycarbonate, Sikaflex and the original self tappers. The latter were not supremely successful and the resultant leaks were blamed on my not being able to tighten things up.

Attempt two was with polycarbonate, Sikaflex and through bolted machine screws. Blame on the poor result was given to the fact that the job was done on a warm day and the Sikaflex went off too quickly.

Attempt three was with perspex, Tiger Seal (used on car windcreens) and longer self tapping screws biting into wood on the inside. Flexing, incompatability or incompetence is getting the blame this time.

I suppose I could always glass up the window holes and put another striplight inside for extra lighting.

Curiously on the starboard is the original factory fitted window. Crazed to hell but watertight
Skykomish E29 11 years ago
I know it is probably astupid question, but it definately is the window thats leaking and not ingress from a deck fitting draining down on the inside of the core to the low part of the ceiling which naturally is the top of the window surround on an Achilles. I only ask as I would have thought that the last attempt would hve been as water tight as you can get.
Alternatively could it just be condensation?
Super Snoopy 050 11 years ago
We tested with a hosepipe, there was a visible leak just forward of the bulkhead in the fore cabin.
Aquila 007 11 years ago
I replaced mine on Aquila last year. Can't remember exactly what I used in the end acrylic or perspex. I was told that one is more likely to scratch the other more likley to craze.

The originals were held in by 3 or 4mm self tappers. There was no way that they would hold a second time so I replaced them with machine screws with dome headed nuts inside (96 in total, which my wife helped me fit on christmas eve). I mounted the perspex on 3mm thick closed cell rubber sheet, and cut the windows out after it was fitted. The 9m has a single plastic sheet with three cut outs for windows. To date the seal has been perfect and the black rubber behind the tinted perspex looks much better than it did when you could see the gelcoat through the plastic.

Approx costs - windows £110, rubbersheet £20, Nuts and bolts £10 - £15 ish.
santalars 11 years ago
Don't wont to be smart but all the newer Achilles have the same window holes than the older ones as far as I know. So there is still the possibility of putting oval windows in. It just takes Boat - Window rubber profil seal (that's what it would be called straigt translated from german). If fitted correctly with some silicone filler they are seal, flexible and will withstand waves.
guillainevib 11 years ago
What is wrong with nuts and bolts? Aquila's method has my vote.
Tocviria 11 years ago
I will try glued. Crazing ocurrs a lot faster in my climate.And the cracks begin sooner from the outside to the screwholes.
busy home [deleted] Posted 11 years ago. Edited by busy home (member) 11 years ago
Ian says,, Clean well with Sika cleaner, important ..yellow top.
Mask window area Apply black top
Sika primer.
Use 295 Sika uv resistant
If using screws do not tighten to much and use rubber or stainless washers between boat and windows,,
Apply a second bead if needed.
Skykomish E29 11 years ago
Sorry Ron your last wasn't too clear was that DO NOT use washers, or USE washers to ensure not overtightening the screws?
Tocviria 11 years ago
Ron If I will only use glue should I use washers as well?. Sikaflex say that a 3mm thickness is necessary to achieve complete structural strenght for the SFlex 295. Any way I will use nylon washers.I already bought the Hot Glue Pistol which has a power of 250W, this was the most powerful I could find I hope it will be OK Thanks very much Antonio
Tocviria 11 years ago
What is best for windows? Polycarbonate(Lexan) or Polimethyl Methacrylate(Perspex,Plexiglass,Lucite) , of course price is important.
busy home [deleted] 11 years ago
I m back from my holls,

Yes use washers but between window and boat to allow a gap .Do not squesse all sika out
Im not sure about use without screws .The important thing is to not squease the sika out! I will ask Ian to make sure.. and the other questions,
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