Sikaflex Caulk Question

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footer
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Sikaflex Caulk Question

Post by footer » Tue Feb 26, 2019 12:18 pm

I was reading a blog about the types of caulk you use to caulk in between the top deck boards. They were talking about using sikaflex and 3M 5200. Seems the 5200 is good, but it is four times as expensive and is harder and more permanent.
The Sikaflex White seems to be the more desired product.
Well, I went to get some at Lowes (which they carry in stock), but to my surprise, there are like five different types. I am assuming the construction grade is the one to use.
Can anyone enlighten me on this or any other product to use?
I plan to buy the 5200 in Mahogany for caulking a couple of seams I am going to have, but I only need one tube (it is between $22 and $32 a tube, depending where you buy it).

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Jimbob
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Re: Sikaflex Caulk Question

Post by Jimbob » Tue Feb 26, 2019 12:57 pm

I would highly recommend boatlife caulk. You can get it at boat supply houses. It is non-silicone and sand-able. Lots of classic boat restorers us it. Important to get a caulk that you can varnish over.
I would stay away from 3m 5200, don't think you could remove later if you need to.
See my link below to see what I used and the results:

https://www.glen-l.com/phpBB2/viewtopic ... fe#p197417

Jim
Jim Neeley
Building a Barrelback in Sacramento, CA
viewtopic.php?f=15&t=28089#p172969

TomB
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Re: Sikaflex Caulk Question

Post by TomB » Tue Feb 26, 2019 3:21 pm

I agree with Jim. I like the Boatlife polysulfide Caulk. It is workable, not too sticky, and cleans up (acetone or naptha?). I am using it to mount hardware and spray rails. I'm unsure about use on seams, is it too flexible under varnish and maybe crack the varnish? would like to know.

5200 is the most sticky stuff out of the tube I've worked with. Sets up hard and is permanent. You can get it out of the seams with a router or a chain saw. :mrgreen:

There is a discussion of deck seams...where???

Tom

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Roberta
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Re: Sikaflex Caulk Question

Post by Roberta » Tue Feb 26, 2019 3:42 pm

I like 3m 4000 uv because it has UV protection.

Roberta
Roberta "Queen of the Boat Builders"
Built Zip "Oliver IV", Super Spartan "Jimmy 70", and Torpedo "The Glen L".

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Jimbob
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Re: Sikaflex Caulk Question

Post by Jimbob » Tue Feb 26, 2019 3:55 pm

Tom,
Cleans up with good old mineral spirits. Varnish goes over it just fine. The caulk isn't all that flexible after it sets up. (takes a couple of days to set up and longer for a full cure). Don't forget varnish is somewhat flexible itself. There is a section on deck seams in the glen l site under support knowledge base.

Jim
Jim Neeley
Building a Barrelback in Sacramento, CA
viewtopic.php?f=15&t=28089#p172969

TomB
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Re: Sikaflex Caulk Question

Post by TomB » Tue Feb 26, 2019 4:22 pm

Jimbob wrote:
Tue Feb 26, 2019 3:55 pm
The caulk isn't all that flexible after it sets up. (takes a couple of days to set up and longer for a full cure). Don't forget varnish is somewhat flexible itself.
Good point. Varnish is flexible. I'm using 2 part poly which is less flexible so I will probably seam with epoxy.

I've used 4000UV too (not seams), worked great.

Tom

footer
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Re: Sikaflex Caulk Question

Post by footer » Tue Feb 26, 2019 6:57 pm

Well, TomB, now I can't find that conversation, but I'll keep looking.
Ok, so, my intention was to epoxy over the wood, then caulk, then spar urethane the top coat over all. Am I on the right track with that and would that change the type of caulk I should use?

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Re: Sikaflex Caulk Question

Post by TomB » Tue Feb 26, 2019 7:47 pm


footer
Posts: 187
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Location: Plainwell MI

Re: Sikaflex Caulk Question

Post by footer » Wed Feb 27, 2019 5:08 am

Thanks for the info Tom. That's quite a bit to take in. So, it appears there isn't just an easy one way answer, lol. My original intention was to stripe in with Aspen as I did on my dash. After doing that I realized (after it yellowed quite a bit) that's not the color I was going for. Since all my accents; Gauges, Seats, and Steering Wheel, are white, I wanted to go with the white stripes and that would mean Caulking, Painting, pin striping, or putting in some kind of plastic strips.
I know the Spar Urethane will cause anything to yellow a bit, but I'm OK with that. I just want to be sure, whatever I put in is going to look good, hold up to the environments, and be easy to use.

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