silicone sealant not curing

[BillZ]

I used silicone sealant (100% RTV silicone rubber)on some seams of my woodie tear. The instructions say it drys to the touch in 1 hour and fully cures in 24. I checked it 24 hours later and it was still as wet as when I first put it on. Does silicone go bad?

[eamarquardt]

http://www.dymax.com/blog/?p=990

Be patient. Remain optimistic.

Cheers,

Gus

[bobhenry]

If it was old stock that may have frozen it will react weird. Some sets up in the tube like concrete others are watery and runny and will not set up at all. I would purchase new stock and remove what you can and reseal.

[48Rob]

Does silicone go bad?

Yes.

Most have a shelf life of 12 months from time of manufacturing.
Some are a little longer.

Rob

[BillZ]

Ugh!
Thanks for the replies. I also contacted the maker and they said what I had was old and I should remove it and replace with new.
It would have been helpful if there was something said about shelf life on the tube!

Be patient. Remain optimistic.

Cheers,

Gus

That's what I was thinking.
I'm not going camping for a couple more weeks and wonder if it might cure over that time because it will be such a pain to remove. Besides the fact that I don't know if turpentine will hurt the surface.
I wonder if scraping the worst of it off and the new applied on the old will bond and cure?

[BillZ]

Ugh!
Thanks for the replies. I also contacted the maker and they said what I had was old and I should remove it and replace with new.
It would have been helpful if there was something said about shelf life on the tube!

Be patient. Remain optimistic.

Cheers,

Gus

That's what I was thinking.
I'm not going camping for a couple more weeks and wonder if it might cure over that time because it will be such a pain to remove. Besides the fact that I don't know if turpentine will hurt the surface.
I wonder if scraping the worst of it off and the new pressed into the old will bond and cure?

[Breytie]

Ugh!
Besides the fact that I don't know if turpentine will hurt the surface.
I wonder if scraping the worst of it off and the new pressed into the old will bond and cure?

Ouch, that is a real bummer. Normally turps does not attack cured finishes, but always test first in an inconspicuous spot.
Are you sure the turps will remove the uncured sealant? I use a sealant remover from SOUDAL that contains some citrus oils and it makes even cured silicone and acrylic water removable.
The bad sealant will stop the good stuff from adhering properly and may even slow or mess up the cure. Scrape and rub off as much as you can and then use the recommended solvent to wash away the rest.
I hope the manufacturer or seller will replace the bad stuff?
I hope this turns out good!

[BillZ]

Ugh!
Besides the fact that I don't know if turpentine will hurt the surface.
I wonder if scraping the worst of it off and the new pressed into the old will bond and cure?

Ouch, that is a real bummer. Normally turps does not attack cured finishes, but always test first in an inconspicuous spot.
Are you sure the turps will remove the uncured sealant? I use a sealant remover from SOUDAL that contains some citrus oils and it makes even cured silicone and acrylic water removable.
The bad sealant will stop the good stuff from adhering properly and may even slow or mess up the cure. Scrape and rub off as much as you can and then use the recommended solvent to wash away the rest.
I hope the manufacturer or seller will replace the bad stuff?
I hope this turns out good!

Thanks for the info. My sealant was 6 years old so I don't expect a replacement. When the tube says "100% silicone" I figured that there wasn't anything in it that could go bad. Also, no mention of shelf life at all on the tube.

Looks like I have at least a few more hours of work before I can be done.

I started working on the hatch months ago. This was the last step in a finishing experiment that I will reveal to the forum when I am more certain of the results.

[jonesnforcampin]

Dont know if you got all the old stuff cleaned off already, but my Dad uses silicone a lot with countertop installs and says 409 works best. With it being a cleaner probably won't damage any finishes.

[David S]

do not use 409 on painted gloss or clear coated gloss surfaces,and don't ask me how I know.

[jonw]

DAP make something called Silicone-B-Gone that works well. I've used it before when replacing my vent fan and hurricane hinge that had both been glued/sealed with silicone caulk. It still requires some time to work and elbow grease, but it does work.

[bobhenry]

The active ingredient that you smell when using silicone is cetyl alcohol. It is what keeps it soft and pliable until it flashes off. Perhaps it would remove the mess or at least soften it to where some mechanical means would work ( think plastic putty knife ) .