Advice on refixing windows needed

J

John7

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I would be very great full for some suggestions. We replaced our VergoVoyger windows 3 years ago. They are screwed onto the cabin with a sealer. Unfortunately our window supplier failed to drill the screw holes over size to enable larger screws to be used. So the original ones had to be used. I used 3M Marine Silicon, after cleaning with acetone. One tube failed to cure and the scraped off mess was taken back to my chandler (who did nothing!). Ever since we have had a degree of leaking. When I tried to tighten the screws it was clear the original holes were failing so I took out the worst screws and pushed epoxy paste into them. This has been a partial success but it was clear the silicon hasn’t adhered to either the plastic window or the fibreglass.

The result its clear we will have to redo them again. Next time I think I will clean out the old screw holes and fill with thickened epoxy. I would be grateful for suggestions as to the best way to then refit the windows?
Would drilling pilot holes in the new epoxy using them, or fix the windows in place and drill through the window holes be best?

Which is the best form of seal, I don’t trust using silicone again. Originally a wide adhesive coated sealer foam was used but I can’t locate what it was/is or where to get it from or alternative sealants.

Any suggestions will be gratefully received.


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Have you done a search of the forums? The link below goes to a similar question. If you have any further questions ask away. Click on the blue below.
<A target="_blank" HREF=http://www.ybw.com/cgi-bin/forums/showflat.pl?Cat=&Board=pbo&Number=449972&page=&view=&sb=&o=&vc=1>http://www.ybw.com/cgi-bin/forums/showflat.pl?Cat=&Board=pbo&Number=449972&page=&view=&sb=&o=&vc=1</A>
Paul

<hr width=100% size=1>" there is nothing-absolutely nothing-half so much worth doing as simply messing about in boats".
 
Thanks- yes I had done some searches-indeed spent most of the morning doing so.
Most information found is dealing with framed windows-my ones are screwed over window cut outs in the cabin. What I'm looking for is advice on sources of sealant. As far as I can see due to the softness of the windows etc you can’t screw/bolt them up tight as they will crack. The sealant has got to adhere to cabin and window to provide the seal. It is this that the 3M Silicone failed to do from the start. The tape will need to be thick enough to allow for unevenness and flexible to cope with expansion/flexing etc but must be waterproof.


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MG Yachts (Northshore) used neoprene tape on all windows. They never leaked. Problem with sealants in this application is that it is squeezed out as you tighten the screws.

<hr width=100% size=1>my opinion is complete rubbish, probably.
 
One tip I read about some time ago was to fit a stainless washer netween the window and the boat so there was always sealant and it didn't get squeezed out. If you can get them use dome head or Pan head screws and these shouldn't crack the plastic, but they won't be flush like countersunk screws.

<hr width=100% size=1>dickh
I'd rather be sailing... :-) /forums/images/icons/smile.gif
 
I recently replaced all my windows and used the self adhesive tape. It is brilliant and can be bought from Frank Halls & Sons at Walton on the Naze. Unfortunately I don't have their number to hand but 118 500 will bw able to help you.

Good Luck

Kim

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Have just done our Venturer (another Newbridge boat) which has similar windows - Used 25mm x 3mm self adhesive neoprene from ASAP supplies (about £7.50 for 10m with the vat). 30mm wide would have been ideal, as the borders around the windows were this width.

Another source is ARCO (who have a web-site) and I think do 30mm wide tape & also neoprene sheet. Cheaper than ASAP, but £6 postage meant that I went with ASAP as I needed some other stuff from them anyway. Don't yet know if they've sealed, - only did them yesterday! Certainly easier to get a neat job than with sealant, but don't underestimate the task of cleaning up the old sealant.


Andy

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Silicone really does not adhere to plastics very well so will always be likely to leak.

If neoprene foam (with adhesive one side only ) is applied to the cabin side grp the window sheet can be bolted on compressing the foam and making a watertight seal that will last.

bolt the windows on first without the foam to get the bolt holes in the right place then unbolt, stick the foam to the cabin side, make a small hole in the foam for the bolt then push the bolt through the window and the foam. Gently tighten up the nuts. Trim off the surplus foam. Use nyloc nuts on the inside to stop them coming loose.

<hr width=100% size=1>Richard
 
On our last boat - a Cobra 750 with polycarbonate windows - we used the black Sika product (expensive) designed for the job and replaced the self-tap screws with machine screws. We put teak strips on the inside with domed nuts and it looked quite nice. If I did it again I would use the neoprene tape instead of a sealant, but I would still bolt them rather than use self-tappers. I don't think any sealant can hold a long window against the thermal expansion that the often-darkened plastic undergoes in the sun, so in effect the sealant is just like a tape anyway, not fully stuck to one surface or the other? It's hard to stop the sealant looking messy under the window - painting the gelcoat surface black helped a bit.

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We have just replaced 10 windows on our maxi 120 over window cutouts as you have. I completely agree with the beneteau-305-553 post.

Use neoprene tape, which you can get from a variety of sources if your chandler cannot help or local boat builder. Ours was supplied by the window maker but I know you can get it from Wilkes in Tollesbury and I'm sure there are other sources. Pressure keeps this in place rather than squeezing it.

Also agree that it is much better to use interlock screws through the GRP. It is more expensive but especially if you are going o0ff shore it is much stronger and more waterproof. Line up before putting the sealant on and be aware that the installation will put a strain on your friendship/relationship with whoever helps you!

Put a sealant bead round the outside of the windows both for neatness and drip protection.

Finally - do one window at a time. It's a b--r of a job and takes ages and every time you take a window out you are confined to the dock. We learnt this the hard way.



<hr width=100% size=1>Sarah&Pip
 
I helped a mate replace his windows last season - he used a Sika product - and no screws. Basicaly glued the windows onto the cabin sides. The windows were oversized, and shaped to a more modern shape than the cut outs, with the éxtra' window area screened off black. But the area glued was about 15 - 20mm around the edge. Also incorporated a neoprene strip on the inside edge of the opening, to keep the black glue/sealant from the interior. Propped the windows with sticks to the safety lines around the boat, and left overnight. Did one side one day, the other side the next. 2 people to position the window, & hold it while sticks positioned. Definitely no leaks, and it still looks good.
Cheers
Ian

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Your taped double sided foam is a 3M product which is supplied on a wide reel, and then the correct width cut off as required - see your local 3M wholesaler.

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Agree with all the other posters. Had a severe leak on my Sigma 33, same style windows. Used neoprene tape. Took some convincing as I had already spent money on Sikaflex and required primers etc. Salford House Windows in Otford near Sevenoaks--see back of PBO -advised this. Use 3mm. If you use thicker and the perspex is thin you can get bowing. I used 10mm perspex. I got the supplier to drill the perspex 1mm wider than the bolts to allow for expansion. I then used bolts with Interscrews--a female nut that fits over the end, much neater but not cheap. You drill the boat so the the female goes into the coachroof leaving a nice flush head. I got mine in stainless from Anglia Stainless somewhere in Norfolk. Trouble with mastic like Sika is if you ever break the window you probably rip the gel coat of removing the broken bits. My windows were bone dry afterwards.

<hr width=100% size=1>L.A.R.Ferguson
 
interested to hear of your experience with sikaflex. was it 295uv? we used this and it cost up to £100 per window so you can imagine how p**** off we were to find it starting to separate after 18 months.

we plan to re-fit with neoprene for this season, any problems with the changeover?

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I never used mine, even though I had forked out for the 295UV. Make sureyou clean it all off. And I put the interscrew nuts on the inside. To pull tight the hole may need to be slightly larger on the coachroof-experiment going up if you need to-and get someone to help it's much easier with two.

<hr width=100% size=1>L.A.R.Ferguson
 
[ QUOTE ]
I never used mine, even though I had forked out for the 295UV. Make sureyou clean it all off. And I put the interscrew nuts on the inside. To pull tight the hole may need to be slightly larger on the coachroof-experiment going up if you need to-and get someone to help it's much easier with two.

<hr width=100% size=1>L.A.R.Ferguson

[/ QUOTE ]

How do you clean Sikaflex?

I've removed my windows and am tryign to use a paint scraper to remove the stuff.

But, I'm scratching the gelcoat so I'll need to sand & use finishing paste when done to get the surface all sweet again.

Top tips Anyone?

Haven't tried it but somethign MUST disolve that awful stuff without damaging you or the gelcoat...

Was tinking of using a nylon brillo...


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