What is the difference between Marine Sika 291 and "builders" polyurethane Sika?

[Ric]

What is the difference between Marine Sika 291 and "builders" polyurethane Sika?

The local builders merchant sells 300g tubes of Sika polyurethane adhesive sealant for half the price of a toothpaste tube of Sika 291 in the marine chandlers. Is there really much difference? It doesn't feel, smell or look much different.

 

[TimBennet]

There's lots of alternatives if you don't want the 'marine' moniker.

This stuff has proved effective: http://www.toolstation.com/shop/Adh...e+PU40+Sealant+310ml+White/d180/sd2350/p67949

 

[VicS]

The local builders merchant sells 300g tubes of Sika polyurethane adhesive sealant for half the price of a toothpaste tube of Sika 291 in the marine chandlers. Is there really much difference? It doesn't feel, smell or look much different.

That'll be Sika 221 ? ITYWF Roger Shaw has looked into the builders' products vs the marine products and will tell you to save your money and use the the builders' product.


CT1 is another product often recommended on here. It is not a polyurethane though.

 

[Sneaky Pete]

Licence to print money

Anything with suitable for marine application means you can at least double the price.

 

[Ric]

VicS, yes think it is 221. Tube is down on the boat so will check later.

 

[vyv_cox]

I have been using Toolstation's PU40 as a substitute for Sikaflex 291 for a couple of years now, both in Greece and in UK. It looks and feels like the same stuff and up to now it performs equally well. Less than £5 per tube last time I looked.

 

[ronmarson]

I use 'Tec7' and it seems to do the job.

 

[Mistroma]

I suspect it's not just the marine stuff, Maplin are quite pricey for some things. I needed some neutral cure sealant for some electrical connections a few years back and grabbed some from local Maplin. I needed some more a couple of days ago and found that it is £5.29 or £5.59 for 80mls at Maplin. Toolstation opened a new local branch recently and they sell 310mls neutral cure silicone sealant for £2.78.

Half price for about 4 x the quantity. No-brainer as all I'm looking for is a sealant that won't corrode connections as it cures. I've found that most Toolstation stuff seems to be decent quality.

Good to know about PU40 as 291 replacement as well.