Which glue/sealer for trimtab install - 3M5200 or Sika?

[Seppo BNE]

Hi-

Looking into installing a set of trimtabs on a Seafarer..

Was looking into glues/sealers and a bunch of guys in the US seem to use 3M 5200 and others recommend Sika (11F?)
Reading a bit more into it, there also seemed to be a crowd that wanted to avoid 3M 5200 as it stick *forever* and be next to impossible to unscrew.
On a set of trimtabs, I think it could be good as you really don't want them coming loose.

Would anyone have thoughts on a good sealer/glue to look into??

Seppo

[Moonlighter]

I would imagine that the main point of the sealant on the tabs, presumably where they attach to the boat, is to seal rather than to adhere - after all, there are quite a few screws used to actually do the work of fixing them to the boat.

If it was me I would just use the Sika 291 marine adhesive/sealant. If you ever damage a tab and have to remove to replace or repair, you will want to be able to get them off without damaging the surface they are attached to, and also you will want to be able to clean off the old sealant without having to use a grinder!

[PROS]

Fixtech Fix190 FWT

[scottar]

3M 5200 is like angry Sika on steroids. Good for when you want to glue something on and never ever ever ever, want it to come off. Personally I used Fixtech 15 as it is really only a sealant in this case - the structural strength is provided by the screws and the Fixtech product is a whole lot more manageable than Sika, let alone the 3M. One thing to be cautious of when you mount your tabs on the Victory, is that the very top outboard side screws, (depending on you tabs mounting footprint) may well end up either above the floor line or right on the floor line. Mine ended up just above so I had to seal off the holes from inside the cockpit - had to pull the batteries. There is no timber where you will be mounting the tabs - you are screwing into fibreglass only so make sure your holes are the right size for the screws.

[The Woo]

Sika 291.
Given the high loading that tab mounts see it's always best to rely not just on the retaining screws, but to have a structural sealant like 291 to share the load and eliminate the opportunity for screws to work loose and allow movement and then water ingress.