# expired silicone?



## Shinosuke

Is it alright if I used expired silicone? I found some black GE silicone at the store but it's over a year out of date. I'd mostly be using it to cover carved GS on a background so I can get cocofiber to stick to it.


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## josh_r

I would definitely not use it. Expired silicone will not cure all the way and is a big time mess as a result. I know from experience. Do yourself a favor and buy some fresh stuff 

Josh


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## guppygal

The problem you may run into is that it has dried up. We had some unused silicone sitting around the house for a while, maybe a couple of years, and when we tried to use it, nothing came out. We had to pitch all the unopened dried up silicone ~

Other than that, there shouldn't be any problems.

kristi


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## randommind

josh_r said:


> I would definitely not use it. Expired silicone will not cure all the way and is a big time mess as a result. I know from experience. Do yourself a favor and buy some fresh stuff
> 
> Josh


Same here. I didn't see a tube had expired and used it to seal around the false bottom and secure a vert kit in place.....HUGE mess! It never cured and I am fairly certian the neighbors are still in shock from all the obscenities that came pouring over the fence.


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## beatusb

If you bought it already, put it in your caulking gun and run a thick bead on something like a scrap piece of glass and let it set for 24 hours. If it did not cure, dont use it in your build.

If you have not bought it yet, squeeze the tube and see if it feels like it solidified/cured in the tube. If not and you want to try the above recommendation, go and buy it.


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## Dangerously

It has an expiration date for a reason. It probably won't be hardened in the tube, but like others have said, when you use it it may not cure - ever. But you'll only have that happen once, trust me. It is a *huge* PITA to remove uncured silicone, clean all the surfaces, and start over. After that you'll never use expired silicone again. 

If it was a few weeks expired it'd probably be ok. But a year? You wouldn't drink milk that had been expired for a year, would you?

Honestly, I won't use expired silicone, period. I had one run-in with it on a building project (not pet related), and that was enough to make me pay careful attention to the expiration date. I now throw away tubes after they expire to make sure I don't use them as well.


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## Pumilo

beatusb said:


> If you bought it already, put it in your caulking gun and run a thick bead on something like a scrap piece of glass and let it set for 24 hours. If it did not cure, dont use it in your build.
> 
> If you have not bought it yet, squeeze the tube and see if it feels like it solidified/cured in the tube. If not and you want to try the above recommendation, go and buy it.


I work with silicone on a daily basis for my window work. Do as Beatusb suggested. Expired silicone may harden in the tube or (much worse) it might never cure properly. If you test it and fully cures, feeling like flexible rubber, then you should be fine.


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## Shinosuke

I went back to the store today and it turns out the date I was looking at was the "DOM", or date of manufacture. Say what you will about hardware clerks, 99% of them have a firm grasp of the obvious! 
Anyone know what the shelf life of silicone is? I'm pretty sure that the tubes I got are still good since they have some flex, but I'm still curious. The DOM on the 2 I got are 10/10.


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## Shinosuke

Dow says 15 months. Thanks, google!
Product Q&A Detail - Dow Corning


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