re-sealing plastic windows

simonfraser

simonfraser

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i have plastic windows screwed down on black ? latex which is stuck on the ply/epoxy.

you can see the rain leaking between the window and the 'latex'.

i have tried screwing the window down a bit harder but don't want to crack it.

so, tempted to take the windows off and re-seal with something black and sticky, black silicone if such a thing exists.

i'd rather not mess with the foam as that looks tidy and will no doubt be a pain to remove and do again.

suggestions please :-)
 
Check what Eagle Boat Windows say in their hints and tips and also what they have to offer ..... A non setting butyl compound

Black silicone is available from car spares shops for windscreen sealing but it may not be very UV resistant.

Care needed if you have polycarbonate windows as solvents in some sealants will crack them.

Sika do a sealant specially for plastic windows that is also UV resistant Sikaflex-295 UV. See Sikaflex Users Guide or Sikaflex Marine Handbook
 
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As an interim measure until you decide what to do, use Captain Tolley's Creeping Crack Cure, available from chandlers.

I have no connection with the product other than I have used it for years to effectively deal with problems like the one you've got. Just a few drops does the trick, sets in half an hour.;)
 
Avoid silicone if at all possible. It has poor mechanical strength, poor UV resistance and almost no adhesion. OK in your bathroom but inferior on a boat. Use the stuff made for the job, as described above. Sikaflex 295 has always been good for me, although this is not the stuff recommended by Eagle.
 
The proper silicone is best to use with plastics. As posted many sealants will react badly with plastics. The silicone formulations at a chandlery are different from what you would purchase for a bathroom. The best is Dow 795 structural silicone adhesive. Definitely not bathroom caulk! Boeing uses it to attach the ports to the 747. No other fixings are used. Butyl tape will also work and is available in black - never really cures and stays flexible - it's holding your car windshield on.
 
vyv_cox said:
Avoid silicone if at all possible. It has poor mechanical strength, poor UV resistance and almost no adhesion. OK in your bathroom but inferior on a boat. Use the stuff made for the job, as described above. Sikaflex 295 has always been good for me, although this is not the stuff recommended by Eagle.
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I'm sorry, I don't agree.The fact that silicone does not bond is a plus.It aids removal when time comes.It doesn't have to bond because it works in compression.As to UV resistance I never had any problems.In order for silicone to seal properly a bead of sealant should be applied first and allowed to cure for an hour or two.Then prior to fitting the window another fresh coat is laid and the perspex only lightly screwed in place.The next day the screws can be done a bit further.This method creates a gasket that can be compressed further if it's leaking. Screws must never be countersunk in acrylic,by the way.The material expands quite a lot in the sun and the compression forces will create cracks.For the same reason screw holes must de drilled oversize.
 
I would use neoprene tape. Easy and works very well, used it to rebed the windows on my Sigma 33. Talk to the people near Tonbridge. Can't recall their name but they advertise at the back of PBO>
 
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