getting sealant to stick!

[standy]

Sticks to anything, right? That's what I thought, anyway.

Had my bathroom tiled by a pro recently (about three months ago), but the sealant around the bath has come away from the plastic :evil: . I've removed all the old stuff using a razor and some magical sealant remover (it actually worked :D ) and cleaned with meths. Just picked up the sealant and it says on the back that plastic surfaces (I'm thinking this is where the tiler went wrong, perhaps) need to be primed with a product called Primer FD (Mapei). Anyone know where to get this product? I got the sealant from Screwfix (Mapesil AC beige) but they don't seem to do it - nor does anyone else in the UK according to google :? . Is there an alternative way of priming the plastic bath to ensure the sealant doesn't come away from it? Please help - the wife is on at me cos she can't have a shower :roll:

[stoneyboy]

standy,
In all the bathrooms I have fitted I have never experienced this problem, the silicone sealant has never pulled away from either the bath or tile edge.
Suggest you look for a cause for this problem - what was used to clean the bath prior to re-tiling. From your description I take it the bath was an existing one so it may be that soap residues from shower gels may not have been cleaned off before sealing.
end

[rosebery]

"Had my bathroom tiled by a pro recently (about three months ago), but the sealant around the bath has come away from the plastic :evil: . I've removed all the old stuff using a razor and some magical sealant remover (it actually worked :D ) and cleaned with meths."

Then you should have got him back in to fix the problem. 3 months isn't acceptable. As you've done something yourself now you have no recourse to the tiler to correct a fault in the work - assuming he was at fault - see later.


"Just picked up the sealant and it says on the back that plastic surfaces (I'm thinking this is where the tiler went wrong, perhaps)"

Just because the sealant you have bought suggests that doesn't mean that the sealant that the tiler used was either the same sealant or required a primer. It would not be correct to assume that this is "where he went wrong"


"need to be primed with a product called Primer FD (Mapei). Anyone know where to get this product? I got the sealant from Screwfix (Mapesil AC beige) but they don't seem to do it"

I think you'll find that the wording on the tube suggests that FD is required where you are sealing concrete, wood, painted surfaces etc. Yes I know it says plastic too but should be OK on ceramics and the bath which I'm guessing is acrylic.


" - nor does anyone else in the UK according to google :?"

I think you'll find that Mapei UK do!


"Is there an alternative way of priming the plastic bath to ensure the sealant doesn't come away from it? Please help - the wife is on at me cos she can't have a shower :roll:"

First question is does the bath move? Are there wooden battens underneath the edges of the bath adjacent to the walls. If not it's inevitable that there will be movement and inevitable that the sealant will fail sooner or later. That would not be the tilers fault and it will happen again.

Second question. Was the bath filled approx 3/4 full prior to sealing by the tiler? Did he the tell you to leave the water in the bath until the sealant had completely cured? If he didn't theres probably been movement leading to sealant failure. If he did and you didn't theres probably been movement leading to sealant failure.

FWIW I'm not at all convinced you need to prime.

Cheers

[standy]

Thanks both very, very much. I shall just get on and do it then.

I know that the tiler didn't fill the bath prior to sealing (I was under the impression he was quite keen to get away - Friday afternoon, you see), but it was a brand new bath, so no residue. I'm pretty confident it was fitted properly with batons so it hasn't moved...so I'll make sure all residue has gone, the bath is 3/4 filled with water and I leave it like that until the sealant has gone off.

Thanks fot the advice.

[rosebery]

"I know that the tiler didn't fill the bath prior to sealing"

Then he WAS at fault. Irrespective of movement of the bath it wi flex when weight is put in it. Water plus you = quite a bit (- not being rude you understand).

What happens is that if weight is not put in the bath when the sealant is applied as soon as you do put weight in it stretches the sealant. Constant stretching (filling the bath) and subsequent compression (emptying it) causes the sealant to fail.

If you fill the bath 3/4 full before sealing then when you empty the bath the sealant is compressed and when you refill the bath yes it stretches again but not beyond the point where it was originally sealed. As it never gets beyond that point it isn't under stress and therefore should not fail.

Unfortunately, as I've already stated, as you've started remedial work he won't feel inclined to come back to fix it. Never mind.

Cheers