Sealing for main windows

[riki]

Hi friends.


I am replacing the sealing of the main windows of my catamaran because the old one was weared and had some leaks. I am using sikaflex but i am not completelly satified about the results being the silicon not even all around the windows. I am using a small spatula, fingers and soap but was wondering if there are any tips to make the final result looking better OR if you suggest to use a rubber seal and stick it with the sikaflex.
All suggestions welcome.
Thanx.

[coopec43]

When I did mine I used Fixtech.

I followed instructions and masked the edge of the glass and the cabin side about 10 mm out from the edge of the glass. I used a cartridge gun to deposit the adhesive and spread it very evenly using my thumb. (I think I used acetone to clean my thumb which was no trouble)

The masking tape was left overnight and removed the next day.

Not hard at all!

[slug]

Originally Posted by riki

Hi friends.


I am replacing the sealing of the main windows of my catamaran because the old one was weared and had some leaks. I am using sikaflex but i am not completelly satified about the results being the silicon not even all around the windows. I am using a small spatula, fingers and soap but was wondering if there are any tips to make the final result looking better OR if you suggest to use a rubber seal and stick it with the sikaflex.
All suggestions welcome.
Thanx.

Sounds like you are doing it correctly

I’m never able to pull off perfect caulk bead

Always an overlap or drag mark

Some caulking is easier to use

What number is your sika



I

[riki]

Originally Posted by coopec43

When I did mine I used Fixtech.

I followed instructions and masked the edge of the glass and the cabin side about 10 mm out from the edge of the glass. I used a cartridge gun to deposit the adhesive and spread it very evenly using my thumb. (I think I used acetone to clean my thumb which was no trouble)

The masking tape was left overnight and removed the next day.

Not hard at all!

Hey, thanx for your answer. It's more or less what i've done but using instead sikaflex anti UV silicon. The problem is that it's not easy at all to apply the same pressure all around the windows so the final result is looking not as i would like. Looks corrugated, not even.....

[riki]

Originally Posted by slug

Sounds like you are doing it correctly

I’m never able to pull off perfect caulk bead

Always an overlap or drag mark

Some caulking is easier to use

What number is your sika



I

Hi.
I am using sika 296 UV.
I was considering if it's possible to use a gasket T shaped 3/4cm thick and glue it with sika. In that case it should look perfect if i find the right gasket but i don't know how safe/durable can be.
Something like this (the smaller one):

[riki]

Or like this one fixed with sika:

[tarian]

I used siki 291i On 2 large front poly carbonate windows , and used white spirit on a rag and smoothed along the siki to make it even , but make sure you have the tape on as it gets every were, no need to splash the cloth just a dab to work , also if not working on the first beading wait until it drys and re bead it with a smaller amount and use the white spirit to create a even surface.

Using white spirit has not damaged my sealant not has it leaked any were in 3 years and I get a lot rain

Small amount is all that is needed

clean rag or cloth

steady hand

[bwindrope]

Not sure if there is anything unusual about your windows but if they are a standard mechanical closure, meaning there is a rim on the inside that bolts the outside window tight against the hull, and the sealant is merely a sealant and not used to hold the window in place, then I would highly recommend a good quality butyl rubber. Butyl rubber is permanently flexible, highly sticky and seals windows perfectly. You can get high quality butyl rubber sealant from pbase in Maine.

Every other sealant seals no better and is more of a pain to get off when you replace or remove your windows for some other reason. My .02.

[Hardhead]

I've never been able to get a good aesthetic bead of sealant either. From a distance however, it's really not noticeable at all.

It's just the sort of issue the obsessive compulsive owner fixates on for a while, but most people would never focus on, IMO. Important thing, of course, is getting a good seal.

[CassidyNZ]

Cut the nozzle of the Sika tube in a 45 degree point at the size of bead you need. When extruding the product, run the one side of the point flat on the surface and the bead will be quite accurately extruded.

Start with a small point, try it on some scrap to see the size of the bead then re-cut to get to the bead size you want.

Oh, also, when you screw the window down, don’t take the screws directly to the final tightness, let the Sika set then relighted to compress the joint ever so slightly.

[MikeFergie]

There seems to be a number of Leopard cat issues using Sikaflex products. The issue seems to be the sika not bonding to the acrylic window or coming loose after a few years. As the bond is structural to holding the window in place many of the leopards owners have taken their window out and cleaned them up and used Dow Corning 795.

[rbrentp]

Agree with bwindrope. Used the butyl tape to bed the windows Leaving a 3/8" gap around the outside and not snugging down to hard. Then put a painters tape edge and filled the 3/8th gap with a nice taper using a soapy finger. Gave it an hour. Removed the painter's tape. Beautiful edge. Tightened the screws to finish bedding the butyl and left it alone for 24 hours. 10 months not a drop.

[sailcrazy]

I, too, must add my 2 cents to the Butyl bandwagon. I've never rebedded my main salon windows, but I have rebedded 2 deck prisms and all my chainplates after I took them out and cut a 45* bevel all around them down to the bottom of the deckcap. I used West Marine Butyl...it was EZ to use, very flexible and stays that way, sticks, and seals out the moisture. And none of it leaks!!!

[Disailor]

Lotsa good tips. After applying many miles of caulk, I cut the tip at 45. The length of the caulking gun should be just about as much inline with the gap
as you can manage & almost vertical. Squeeze the handle slowly & when you see a ball of caulk starting to fill the gap, start moving the gun along the gap. With the gun nearly vertical, the point of the nozzle will act as a depressor & force the caulk down into the gap & tool the surface at the same time. The trick is to match the squeezing (to feed the caulk) to the speed of moving the gun along. Keeping the ball in front of the nozzle assures the caulk will go down into the gap & not just bridge the gap. Taping where you do not want the caulk to go is essential & a light touch with a soapy finger makes for a nice joint. Practice on scrap with the same size joint will help.
Acetone should never be used to clean the hands. Skin is permeable to acetone & whatever you've dissolved in it!

[sailingchiro]

I made a complete mess by trying to keep it perfect on 2 hatches. A few days later I applied 395 to two more hatches and my wife needed dinner before I could finish. I didn't have time to clean up my mess. I came back the next day and easily trimmed the excess with a sharp razor blade and it looked awesome. Kind of like 5200. the more we play with it, the bigger the mess. The remaining hatches I applied excess and left them to dry slightly. Then trim excess the next day.