Your thoughts on splitting Silicon...

[tfs]

I came across this a while back and in some rare cases sanitryware need to be primed prior to sseling with a sealant.

The experience I had required the sanitryware to be sealed with Mapei's Primer fd before resealing the area with mapisil ac

I think some types of resins in certain baths and trays can be problematic in terms of getting a good bond.

To the best of my knowledge the primer fd is rather rare and had to be ordered from Italy or Poland.

hope this helps

 

[advancetiling]

google the window man. section on different Silicon sealers high/low modulus etc.quite a good read http://www.thewindowman.co.uk/sealants.htm

 

[kilty55]

hi rich this happened to me using mapei Silicon

check the sell by date as this was the issue with us
the siliconed curled up on tile and opposite surface and came away from the surface

out of date Silicon was the issue

 

[Rich]

Thank you all for your help. The walls are plaster, the bath and tray have not been cleaned with anything and the Silicon is in date. I went back last night, removed the ultra Silicon and replaced with Mapei but Im not convinced that it will hold. It seems to me that tfs and Mosaic girl are on the right tracks, I had thought about a primer but on the tube of Silicon they say that you need to prime with the FD on porous surfaces. Now I have used Mapei, I will be on the phone to them to see what the best plan of attack is. Thank you again all, I will keep you informed.

GO TF!!

 

[user123]

'Release agent' that was the term I was looking for - the release agents for Silicon are not just washing up liquids are they, they are petrol based things like vaseline, oil, petrol, ... and it could well be in those plastics... yes, keep us posted, Rich..

 

[phillacey]

Re: Your thoughts on spliting Silicon...

Hi Rich, was is a stone tile as Silicon doesnt stick to alot of stone tiles very well ?

 

[Ger]

Was the protective surface liner fully removed across the full width of the ledge so as not to act as a Silicon bond-breaker between the Silicon and adjacent ledge that may cause de-bonding after cure shrinkage has occured?

 

[mz30]

Its the protective coating on the white goods that are causing the problem,there will be some sort of oily residue on it ,little bit of thinners or the like should remove it.
Thats why i never ,ever get involved in siliconing thats the plumbers job when he does his final fix lol

 

[Ger]

I have seen cases where installers use white spirits to clean ledges in preparation for Silicon.

White spirits is oil based. You can imagine the consequences!

 

[Rich]

No the tiles are ceramics, as said above thinners is not much cop to clean down with as it can leave a residue. The areas were cleaned down with meths before the first lot of Silicon was done (as this shouldn't leave any residue). The protective coating was removed.

Have had a look at the Mapei FD primer... :yikes: Wow!! that is expensive!

 

[tfs]

Have had a look at the Mapei FD primer... :yikes: Wow!! that is expensive![/QUOTE]

tell me about it:lol:

 

[SJPurdy]

I have this year had this problem on a few baths. The Silicon i was using adhered to the tiles but pulled away from the bath. I tested two batches of this brand in white, and clear against every old scrap of part tube of other brands i could find in my garage; by applying a bead of each to a clean glazed tile. When set i found that some brands were firmly adhered to the tile and needed cutting off to remove them others were well adhered but could be pulled off; but the brand i had been recently using could be easily pulled off clean!
I have now gone back to more reliable brands and used up all my tubes of Ultra for filling air gaps around insulation panels in my loft.
Steve