RTV Silicone

[RT Firefly]

Greetings,
I recommended against using RTV silicone sealant in the "rust spot on deck" thread for these reasons:
1) VERY difficult to remove all "traces" from surfaces thus making painting, varnishing or using other caulk nigh on impossible whilst expecting good adhesion of the new product.
2) Even a trace on a fingerprint will contaminate other surfaces for a long time.
3) Poor resistance to UV thus insuring a short lifespan.
Mr. H in the above mentioned thread asked what alternatives to use. There are much better options available albeit for a higher price but you get what you pay for and choice of a specific alternate product will determine what is "best" for any particular application.
RTV Silicone is GREAT for home toilets and bathtubs but IMO has no place on my boat.

 

[Haylands]

Thanks for the explanation, personally I gave up using it years ago around the house, now use polyurethane instead, as you say, much better all round....

 

[O C Diver]

While I don't generally use silicone sealant, there seem to be a wide variety of them. Regarding U/V resistance, the Pompanette hatches on my boat have the lenses glazed to the aluminum frame with a silicone sealant. When querying the manufacturer about replacing the lenses, they were very specific about using a certain silicone glazing sealant. After 13 years in direct sun light, the silicone looks new, wish the lenses did also.

Ted

 

[Bacchus]

Greetings,
I recommended against using RTV silicone sealant in the "rust spot on deck" thread...

Mr. H in the above mentioned thread asked what alternatives to use. There are much better options available albeit for a higher price but you get what you pay for and choice of a specific alternate product will determine what is "best" for any particular application.

Not to start / continue a best caulk / sealant debate but I agree w/ RTF on this one

I posted some info / links re: rubrail leaks in the Mainship forum

Or you can see my rubrail repair project write-up on my "Bacchus" website - under projects or

Projects Pg 4 Rubrail Hull - Deck Joint Repair Includes several articles re: the +/- and appropriate uses of Silicone

 

[Northern Spy]

I curse previous owners that have used silicone sealants indiscriminately.

And as an ex-submariner A-ganger, I am particularly adept at cursing. We have improv combinations and conjugations that will raise eyebrows of boilermakers, ironworkers, and piledrivers alike; based on firsthand experience. Ask around.

I'm pretty sure that there is a previous owner of a VW Vanagon Westfalia in Saskatoon, Saskatchewan, that is rubbing liniment into a undisclosed nether-region as I write this based upon his poor decision of purchasing a single tube if GE silicon in his sorrid past.

Be warned.

 

[RT Firefly]

Greetings,
Mr. OC. While I do not doubt Pompanette recommended a specific silicone product which they had found provides adequate glazing, it could easily be that they also had found it was the cheapest compound they could get away with AND increase profit margins.
It's not terribly difficult to rationalize spending $4 on a tube of Home Despot silicone as opposed to a tube of 3M 4000 to the tune of $15.
Anecdote from a previous life: I used to do repairs on apparatus which required grease for ease of function. I would refuse to even touch a piece that had been contaminated with silicone grease. The best grease in that particular application was at least 15X the price of the silicone and to save money silicone was what the client used. My client base quickly learned that using the more expensive grease was cheaper than them spending THEIR time and $$ to decontaminate.

 

[O C Diver]

Greetings,
Mr. OC. While I do not doubt Pompanette recommended a specific silicone product which they had found provides adequate glazing, it could easily be that they also had found it was the cheapest compound they could get away with AND increase profit margins.
It's not terribly difficult to rationalize spending $4 on a tube of Home Despot silicone as opposed to a tube of 3M 4000 to the tune of $15.
Anecdote from a previous life: I used to do repairs on apparatus which required grease for ease of function. I would refuse to even touch a piece that had been contaminated with silicone grease. The best grease in that particular application was at least 15X the price of the silicone and to save money silicone was what the client used. My client base quickly learned that using the more expensive grease was cheaper than them spending THEIR time and $$ to decontaminate.

RT the recommend silicone is $15 to $20 a tube and not found at the big box stores. Believe it's designed for the commercial glass industry, not Harry home owner.

To your silicone grease story: Spent 35 years rebuilding scuba regulators which up until 20 years ago were exclusively lubricated with silicone grease that was food grade compatible. The industry then slowly switched to oxygen compatible lubricants in response to elevated levels of oxygen in what had become common diver breathing gases. Try degreasing silicone off a surface you're trying to make oxygen compatible while only using food grade solvents.

Ted

 

[RT Firefly]

Greetings,
Mr. OC. Point taken for the $20 silicone. The point I was attempting to make was way too many Harry home owners have boats (present company excepted). I hear ya on the degreasing...

 

[Haylands]

What annoys me is that it is increasingly difficult to buy quality, even the expensive stuff is now nowhere near as good as it used to be, they keep reducing the amount of NOC's so the quality suffers so you use it twice as often.... how does that work!!!!

 

[Bacchus]

RTF...

Is this a record - three posts w/o a pic / video???

No SillyCone vids???

 

[BruceK]

There are 2 types of silicone sold here, one paintable, one not. Trick is remembering, I think the bathroom surfaces one is not while the roof and gutter version is, pricing is similar. That said, I usually use Sikaflex, or competing brands of polyurethane.
Dielectric grease is silicone grease,right? I used it recently on my shorepower connector, little risk of needing to paint there.

 

[RT Firefly]

Greetings,
Mr. B. Just for you...

 

[Bacchus]

RTF
Now that's more like it... The RTF we all know so well!
Didn't want you going all serious on us