Silicon - What to use, and where to put it

[S&P]

Hi all,
With the arrival now only 2 hours off, I guess I should be stocking up on silicon.
Just wanted to ask for recommendations on what everyone has used for external and internal sealing?
I've seen the Sikafkex name mentioned many times, but they have a lot of different variants.
I was thinking a marine variety, but they also have automotive.
What to choose, and why?
Cheers,
Paul

 

[DaveS]

we use aktek roof and gutter for just about everything on the vans, very workable compared to some brands we tried. I'm not sure what the factory uses but i reckon it's similar

best way to put it on is too apply a large bead, don't cut the nozzle too small i usually have about a 4-5 mm hole.
once the bead is down spray soapy water all over it
then wipe it off with a soapy finger
spray again with water
then a light touch with soapy finger again
then the most important step ....
walk away and leave it to cure, don't try to make it look better

 

[Burnsy]

Good luck with the pick up Paul!

 

[Gavin and Brooke]

No need to answer this as we've gotten it straight from the horses mouth.

Gavin

 

[gwadir]

Look forward to some pics of the new addition Paul.

Dave

 

[Stone Stomper]

For the outside I used white sanitary bathroom silicone as this always stays nice and white after washing the van and underneath just used roof and gutter silicone.

 

[achjimmy]

Dealer ours came from supplied bostik V60. That seems to of worked well. I have used a lot of the black sikaflex on the cars over the years, and bought the white sika for the bathroom in the Expanda . Big mistake it's gone yellow !

 

[Capt. Gadget]

There are a couple different types of sealants acetic cure silicone neutral cure silicone , Acetic cure silicone has that horrible vinegary stink to it and is suited to glass and usually bathroom tiles like the name suggests it uses acid to cure and it drys a lot quicker than neutral cure but there are a few things you shouldn't use it on like galvanised steel or concrete and soft metals as the acid released during the curing process can damage it. Neutral cure is non corrosive and doesn't smell is a good GP silicone takes a bit longer to cure . Generally paint won't stick to silicone once it is dry but there are a few types out there specifically designed to painted over . There are also high temp silicones and high bond strength silicones Just have a look at what you actually want to use it for. Sikaflex is probably one of the most expensive silicones on the market but they have some of the best high bond strength stuff . I find Selly's brand stuff to be over priced and the same result can be achieved with cheaper no name brands, I've used fuller brand quite a bit and have had no issues

 

[AndrewC]

I have given up on silicone for most things. Sikaflex in my opinion is the only way to go. Plenty of the stuff on the roof of my van has lifted that jayco uses and it eventually lets go when exposed to the elements. Sika 11-FC is the best all rounder. A little tip for clean up, use wax and grease remover from super cheap. Its like using water to clean up water based paint, just wipes straight off and make the job look professional.

 

[cruza driver]

There are a couple different types of sealants acetic cure silicone neutral cure silicone , Acetic cure silicone has that horrible vinegary stink to it and is suited to glass and usually bathroom tiles like the name suggests it uses acid to cure and it drys a lot quicker than neutral cure but there are a few things you shouldn't use it on like galvanised steel or concrete and soft metals as the acid released during the curing process can damage it. Neutral cure is non corrosive and doesn't smell is a good GP silicone takes a bit longer to cure . Generally paint won't stick to silicone once it is dry but there are a few types out there specifically designed to painted over . There are also high temp silicones and high bond strength silicones Just have a look at what you actually want to use it for. Sikaflex is probably one of the most expensive silicones on the market but they have some of the best high bond strength stuff . I find Selly's brand stuff to be over priced and the same result can be achieved with cheaper no name brands, I've used fuller brand quite a bit and have had no issues

I have a head ache now :sick: but I did learn a few things :thumb:

 

[DaveS]

I have given up on silicone for most things. Sikaflex in my opinion is the only way to go. Plenty of the stuff on the roof of my van has lifted that jayco uses and it eventually lets go when exposed to the elements. Sika 11-FC is the best all rounder. A little tip for clean up, use wax and grease remover from super cheap. Its like using water to clean up water based paint, just wipes straight off and make the job look professional.

only thing i don't like about sika is it hangs on tight, if we have to take a antenna or roof hatch off to re seal because of a leak 9 times out of 10 we destroy the item trying to cut it off and it adds to the cost in time and replacement

 

[AndrewC]

Having to reseal? I guess that's the down side of not using the right product in the first place

 

[Stone Stomper]

I'm not sure if the product jayco use is wrong but they use an almost putty type of filler that collects the dirt and you can't get it back white again that's why I went over the top with the bathroom silicone as it comes up like new after each wash.

 

[DaveS]

Having to reseal? I guess that's the down side of not using the right product in the first place

not really, main reason we take everything off the roof is because a rock has got under the back of the AC and punched a hole thru the skin from the AC rocking a bit