Sealing windows with butyl tape - is this the right stuff?

Crinan12

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Going to try sealing my windows with butyl tape as I read on here it's the right stuff.

I picked up a roll of this from toolstation. It is labelled as DPM tape. Is this correct kind of tape? It is quite wide but I guess I can cut it to be narrow if I need to.

My windows are bits of plastic screwed to the fibreglass, there is no frame.

Thanks
 

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Refueler

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If I was going to use that ... I would lay the tape along the edge aligned ... fix window - then using a sharp scalpel / box cutter knife - run blade round the window edge removing the excess neatly. Taking care of course to have blade angled so that it does not 'drag' the tape .. maybe douse blade in cleaner to prevent tape sticking to it.

Others I'm sure will answer better than me.
 

Crinan12

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If I was going to use that ... I would lay the tape along the edge aligned ... fix window - then using a sharp scalpel / box cutter knife - run blade round the window edge removing the excess neatly. Taking care of course to have blade angled so that it does not 'drag' the tape .. maybe douse blade in cleaner to prevent tape sticking to it.

Others I'm sure will answer better than me.
Thanks that's a good idea to finish neatly.
You said if you were to use it - would you use something else? My last attempt was with ct1 but it seems to have cracked and is now leaking a bit.

When I googled buytl tape this came up, but it doesn't say buytl tape on the packaging.
 

ash2020

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I used this on my Varne 27 windows, again no frames just acrylic. It worked very well and provided a leak proof seal. Be careful not to overtighten the screws, the area immediiately around the screw hole compresses more easily than the rest and will crack before you think it will.
 

Refueler

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Thanks that's a good idea to finish neatly.
You said if you were to use it - would you use something else? My last attempt was with ct1 but it seems to have cracked and is now leaking a bit.

When I googled buytl tape this came up, but it doesn't say buytl tape on the packaging.

Would I use it ... I have no boats (none of my 5) have this setup.
 

TSB240

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That is definitely Butyl Tape from Toolststion.
I have just used it for sealing my top rudder bearing housing to my repaired GF.
Other little jobs used to repair the internal and external deck level water seals on my mast.
Used to make a large protected rubber grommet seal for the angled entry of the vhf cable into the mast top..
In the past a roll of this stuff helped seal a blown exhaust elbow . The repair lasted for 4 weeks cruising Western isles and back to base in Wales.
It should be in everyone's emergency tool kit alongside gaffer tape and WD40!
I have also used this on windows as it allows them to move in relation to the stressed GF. CT1 is not recommended for use with windows as it can dry really hard with no give.
 

RunAgroundHard

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Scapa 3507 Bedding Tape, is what I would recommend. Butyle sealant that feels like Blutack will also work but can seep oils in high heat. The bedding tape was used on my own framed window refurbishment project which has not leaked a drop in 7 or 8 years of service. The good thing about bedding tape, which is a foam is that it is super easy to apply and has tenacity i.e. it wants to retain it’s shape and does not set.

I have had good experience with butyle on fittings but the tape was a better solution for window frames. My frames also were forced into a small curve in some places as they were not pre bent, and this joints have also remained water proof.

Edit, just looked at the image and it is similar to my roll of butyle. Go for the foam, higher thickness, would be my advise.


http://hadlowmarine.com/Pages/seals-bedding.html
 

Crinan12

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Scapa 3507 Bedding Tape, is what I would recommend. Butyle sealant that feels like Blutack will also work but can seep oils in high heat. The bedding tape was used on my own framed window refurbishment project which has not leaked a drop in 7 or 8 years of service. The good thing about bedding tape, which is a foam is that it is super easy to apply and has tenacity i.e. it wants to retain it’s shape and does not set.

I have had good experience with butyle on fittings but the tape was a better solution for window frames. My frames also were forced into a small curve in some places as they were not pre bent, and this joints have also remained water proof.

Edit, just looked at the image and it is similar to my roll of butyle. Go for the foam, higher thickness, would be my advise.


http://hadlowmarine.com/Pages/seals-bedding.html
Thanks, what thickness would you advise ?
 

pete

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We used butyl tape 1mm thick on boat windows years ago but after a year or two, I guess with the hull flexing we noticed dirt between the tape and window on the corners although it hadn't started to leak. I used it to bed down some deck cleats and though they didn't leak the tape kept compressing and coming out around the edge of the cleat.
 

RunAgroundHard

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Thanks, what thickness would you advise ?

3mm thick was adequate, width fully fitted the frame flange. There is a maximum compressibility limit, see quote below: -

Scapa 3507 bedding tapes

High density closed cell UV resistant PVC foam sealing tape, self adhesive on one side. Available in grey. Ideal for bedding perspex windows, aluminium frames, etc. Easier and cleaner to apply and just as effective as mastic but with the advantage that if you need to take things apart again they come apart easily. Watertight when compressed by 30%.
 

PetiteFleur

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I've used Butyl tape on all my boat windows and they don't leak even after several years. You must fit a stainless washer at every screw/bolt hole so that all the tape does not get squeezed out. The tape I use is 10 x 2mm, Flexistrip is the brand.
 

VicS

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Thanks that's a good idea to finish neatly.
You said if you were to use it - would you use something else? My last attempt was with ct1 but it seems to have cracked and is now leaking a bit.

When I googled buytl tape this came up, but it doesn't say buytl tape on the packaging.
If you Google Damplas double sided tape you will find that it is indeed a butyl tape but I think I would look for something closer to the actual width I required.
.
 
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