If not sikaflex, what?

Croak

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I need to take my windows off and reseal them.

I am aware that sikaflex may inhibit any further maintainance.

So what should I use
 
Eagle Boat Windows say,

"We strongly recommend and supply a non-setting, non-adhesive butyl based compound for bedding in windows, hatches and other deck fittings. The advantages for using this type of compound include:-
• The joint between the window and boat remains moist and therefore allows for some movement that would typically occur during sailing or due to differential expansion rates (particularly important where a Perspex window is screwed directly onto the side of a boat)
• If you discover that your window is not fixed down enough, you can tighten it further to improve the seal and remove any excess when dry.
• The compound is non adhesive and therefore will not damage your boat if the window or hatch needs to be removed.
• The product has a very long service life within the tube and can be used for other sealing jobs in the future.
• It is easy to remove as it hardens when exposed to air. Any moist compound can be removed with White Spirit and a soft cloth."
 
Thankyou all I will look out for some.

The windows are mainly glass but the perspex ones are badly crazed already /forums/images/graemlins/frown.gif
 
I've removed, refurbed and removed again my original windows because I couldn't get a good seal. At the weekend I fitted plastic windows and used SCARPA tape - its kind of a neoprene tape which is waterproof when compressed by 30%. I hosed the windows and it works. Its cheap at about a pound a meter and it is really clean and easy to use. Strongly reccomend this after doing a lot of research and now trying for myself.
 
I used this in my alu windows. Contradictory advice is given - if using the compounds as a gasket don't use the primer and if using on windows use the primer. Having done the job strongly reccomend using the primer otherwise the rubber will not adhere to the frame qand the glass. I've got a bottle of the primer whioch is of no use to me. If you decide to go ahead let me know and I'll post it to you. It will save you a fiver or so.
 
The best stuff I have found is a non setting compound used by caravan makers to bed things like roof vents. It is grey, and never hardens, but makes a completely watertight joint. Any good caravan repairer will have it.
 
I fitted new window 2 years ago I was advised to use Low Modulus Silicone .. (And as I didnt know the difference between low & high modulus I looked it up) & basically Low modulus is more flexible than high modulus.. Good for boats !

I also inserted a stainless steel washer between the fibreglass and the window to insure that when the bolts/screws were tightened up they didnt squeeze all the silicon out, and left a permanant seal of silicone the same thickness as the washer between the two surfaces.

No problems (so far !)
 
[ QUOTE ]
Ah, this may be the stuff Ken, but when you go onto the site they say 'No Stock, discontinued'.
Pity. /forums/images/graemlins/frown.gif

[/ QUOTE ]
Bugger, so it does. From the description NormanE offers that's probably the same kind of stuff. I can, however, sit rather smugly with my remaining supply of 4 tubes of 'Marine Sealant' which should, with care, fulfill my needs for a few years to come.
 
Just to be different.
I like fitting windows with Sikaflex cos it is flexible and an adhesive, thus mechanically adding strength whilst still allowing some movement of the glass/plastic.
I am not sure what 'maintenance' you would need to ever do once the windows are rebedded with Sika. ' Fit it and forget it'.

Remember that the stuff was developed as a car windscreen adhesive across the worlds extreme environments way before it crept into boatbuilding uses.
 
I am glad that Eagle Windows believe in non-setting sealant! This was always used in the old days for timber trim and deck fittings (Sealastik by Simoniz). The great thing is it is still plyable 20 years later.

I think a lot of people who use strong setting sealants always believe it will be someone else who gets the job of removing things 10 years down the line.

Having replaced windows myself I found the sheet neoprene to be effective (for frameless windows as it can be cut without any joints to leak.
 
There is another trick with windows that sit in alloy channels.

Instead of sealant - you use old bicycle innertube. Cut to length after slitting along to form an open u. Fold it round window ... joint at top middle. Blob of car windscreen sealant in frame channel where joint will be ... offer up and close ... bolt up.
Once fitted .... run very sharp NEW stanley knife round frame to remove excess tubing.

Of course your channel may not be wide enough or accept it - but many older boats would work.

/forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif /forums/images/graemlins/cool.gif
 
Don't use silicon its bloody awful stuff! You'll never get rid of all the traces of it without a fight and if you need something to adhere to it in future thats what you'll have to do!
 
I have just replaced all my windows which are frameless Perspex fitting flat onto the outside of the hull with interscrews.
I used a sticky butyl mastic sealing strip called Flexiseal bought from a glazier @ £10 for a 19 metre roll 15mm wide (I used 2 strips side by side) 3mm thick. It slowly gives when you tighten the screws so there aren't excessive residual stresses in the plastic, but it doesn't ooze out so you have a clean edge and don't need to use spacer washers. Seems good so far but only time will tell.
Windows from Project Plastics, Colchester, excellent. Nice bevelled edges and holes all exactly positioned. (Not such a good job on reglazing a Lewmar hatch though.)
Mike
 
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