best adhesive sealant for pvc rubrail?

[John C]

What would be my best choice to bed a new pvc rubrail in. Thanks...

[Charlie J]

sikaflex, forget the # 190 or 265
you will need about a doz tubes

[Bob H.]

John, I used Sika flex 265, after I lagged it to the hull I drilled a series of 1/4" holes and used a serious commercial caulking gun, pumped into each hole until it squeezed out the next, then move down and repeat. Essentially my rub rail is "filled" like a jelly donut. I did seal the top and bottom first and let it kick before I did the filling trick. The bow is a tough area, I used 1/4" bolts to persuade the rubrail to take the shape it neded to be in. I used about a case of Sikaflex. Still a messy job...ask me how I know..BH

[John C]

Thanks.. will pick some up....

[bob lico]

Bob that seems like a great idea to prevent those ugly black stains running thru the rub rail and then streaking the hull sides. Have 144 bolt,nylock nuts,and washers so it would be a monumental job to hold a wrench on all those nuts some no longer accessible . I have top and bottom sealed but some water still gets thru rub rail where the water runs along toe rail then channels into a small area to run off located just in front of Coaming board starting point.some boat manufacturers put a small piece of flexible plastic tuck into back of rub rail and wrap around so water flows around rail. Might look into this.again great innovation!

[GaryG]

I have used a bead 3M 4000UV (which remains semi-flexible) as an exterior seal between the PVC rub rail (that was bonded with 3M 5200) and the hull which needs to be replaced as most of it has deteriorated, due to UV and time (I think this is the 2nd time it will need to be replaced in ~ 12 years, though it was showing signs of needing attention a season or two ago).

I similarly have used use a bead of 3M 4000UV as a seal at the Flybridge molding to cabin top as well as a few other places to seal an exterior panel or molding, which needs to be replaced as well...

There seems to be a strong preference for Sika products from the recommendations for the adhesive bedding ?

Is Sikaflex 295UV (or other Sikaflex product), a better solution for exterior panel/rubrail/etc sealing than the 3M 4000UV ?