Re-caulking teak cockpit seats with CT1

Poignard

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On my boat the cockpit seats are made of marine ply with ca. 10mm thick teak strips glued on and caulked with flexible black caulking, like a laid deck.

The existing caulking is breaking up and I want to renew the caulking and I am thinking of using black CT1. Would CT1 mark clothing; once it has set?
 
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VicS

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On my boat the cockpit seats are made of marine ply with ca. 10mm thick teak strips glued on and caulked with flexible black caulking, like a laid deck.

The existing caulking is breaking up and I want to renew the caulking and I am thinking of using black CT1. Would CT1 mark clothing; once it has set?

Why not use Sikaflex 290DC, a polyurethane sealant specifically designed for deck caulking?

http://www.kjhowells.com/hres/sikaflex_a_users_guide_1_.pdf

or TDS SIS-440 Teak Deck Caulking which is claimed to be better than polyurethane https://www.boatpaint.co.uk/acatalog/TDS-SIS-440-Teak-Deck-Caulking-1.html
( See VAS's comments)
 
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vas

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or TDS SIS440 for which there is not a single complaint?
I've used it in 5 panels in the heads, but they are generally lightly used and not getting much sun.
Springtime I'll lay teak on the aft deck and will use it again for sure.

V.
 

Yngmar

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CT1 may work, at least it claims 100% UV resistance. The breaking down in UV light is what causes sealants to become chalky and mark clothing. It's probably not ideal though and I'd go with TDS-SIS 440 instead, based on having used it 2 years ago for some repairs which are holding up fine. Unlike the Sika product (290dc, I think), primer is not required. Do not use a polyurethane sealant (e.g. Sika 291i), they break down rapidly in UV light and are IMHO only suitable below the waterline.
 

VicS

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Thanks for the advice. Much appreciated. Looks like CT1 is a no-no.

It would be interesting to try it but it'll be a darned nuisance if it turns out to be no good for the job.
My first thoughts were that it would be too soft but in fact it is very slightly harder that the Sikalex or the TDS products
 

Poignard

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It would be interesting to try it but it'll be a darned nuisance if it turns out to be no good for the job.
My first thoughts were that it would be too soft but in fact it is very slightly harder that the Sikalex or the TDS products

I have used CT1 as a bedding compound and it sets to a very firm rubbery consistency but in that application little of it is exposed to sunlight and clothing does not come into contact with it.
 

dunkelly

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i can also recommend the bostik deck caulk . used it the last 3 years with no problems and 25% cheaper than either the tds or sika
 

Malabarista

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Oh dear…I have used CT1 to repair a small section of caulking that came adrift on my anchor locker lid. I had to replace the timber inside the lid as it had been leaking through the hinge screw holes. The lid was soft and spongy so i cut the back off the fibreglass, scraped out all the timber and old ply and replaced it all. Then reglassed it. A small piece of teak was missing so i shaped a new bit ( from a piece i removed when cutting a hole for a new water filler cap) stuck it with CT1 and as i had it in my hand…
So far it still looks ok but I haven’t sat on it yet.
 

Tim Good

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Why not use Sikaflex 290DC, a polyurethane sealant specifically designed ...

+1 it's not that pricey readily available online. Though the last lot I bought had a use by date of one month after I bought it. If you think you'll do the job a while later email the web shop and ask them for a tube with a date as far ahead as poss.

Ensure you use the prime too and some tape at the bottom of the slot.
 
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