Vacuum sealing opened RTV sealant tube.
- Thread starter Jarpin
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No, but it seems like it should work. I usually put aluminum foil over them, which slows down the curing process but doesn't completely halt it.
A combination of aluminum foil + a moisture absorber + bagging (like a ziplock bag) might be enough since these often cure via moisture in the air. But it might be easier to vacuum pack (still might throw a moisture absorber in with it to be on the safe side).
A combination of aluminum foil + a moisture absorber + bagging (like a ziplock bag) might be enough since these often cure via moisture in the air. But it might be easier to vacuum pack (still might throw a moisture absorber in with it to be on the safe side).
Most RTV sealers cure by absorbing moisture from the air. Keep air away, and curing should stop.
Just keep it in the freezer. Beer fridge works best! 
I found an opened tube of grey permatex in my basement that I think was not least 5 yo. Still seemed ok
It technically has an expiration date so trying to preserve it much more than a year (depending upon a multitude of factors like date of manufacture etc) might prove futile.
I also hate throwing it away but I just put it out of my mind and move on.
That said, let us know if you have any success. I actually think this would be interesting for Super Glue and vulcanizing compound
I also hate throwing it away but I just put it out of my mind and move on.
That said, let us know if you have any success. I actually think this would be interesting for Super Glue and vulcanizing compound
I hate wastage too, but most RTV's have a shelf life / expiration date even when unopened anyways.
Most are less than $15-$20 so I think it's just cheap insurance to work with fresh stuff when resealing engines etc
Most are less than $15-$20 so I think it's just cheap insurance to work with fresh stuff when resealing engines etc
I'll just link my reply in a prior topic but see the whole topic.
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Well...was thinking more along the lines of silica gel, calcium chloride, 3A molecular sieve beads, or the like, but yes, I guess rice will do in a pinch (but I'd rather eat the rice).So you're saying to store it in a bag of rice
On a side note (ok, really a complete tangent), awhile back I was thinking of some low cost way of reducing humidity in the house without upping the temps. I came up with the idea of a large container of calcium chloride (placed near a small window), and the container would be thermally insulated on the sides with homemade vacuum insulation panels, and on the top using materials that allowed gaseous/moisture exchange, with a large heat pipe going from the container through a hole in an insulated window insert (XPS foam laminated with S glass cloth+epoxy) as a heat exchanger. (would probably have to put some kind of coating on the copper part that is submerged in the calcium chloride)
Calcium chloride would absorb humidity, get hot, but most of the heat would be re-directed outside.
The problem then becomes, how to regenerate the calcium chloride? Was thinking painted black on the outside large aluminum tray pans, putting thin carbon felt on top of the water-calcium chloride solution in the pans, putting solar reflectors around it, and obviously putting it all in the sun. Theoretically should greatly speed up the water evaporation process. (The only problem is, consistent sun in my yard is on the scarce side, but hot temps/high humidity is already happening so who knows, I might give it a try).
Ok, so I sealed it up after using it today.
@D60 ,@VersysVsWhat and others... We'll have to wait about 3 months or so and recheck. If you're really interested in what happens, set a reminder on your phone for early September and PM me. I'll check it and report back on this thread.
@D60 ,@VersysVsWhat and others... We'll have to wait about 3 months or so and recheck. If you're really interested in what happens, set a reminder on your phone for early September and PM me. I'll check it and report back on this thread.
I use electrical tape on the tip to keep it from drying out.
That would be pretty silly, paying multiple times more for something to solve the problem in order to eat 20 cents worth of rice.
Then again, I save silica packets that come in various products and if I were ambitious then I'd bake them to drive water out to use for this purpose, but I am not that ambitious, it's just a tube of RTV.
Rice is popular because it just works and FYI, you can still eat the rice. It will take 3 seconds less time to cook after using it for this.
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Calcium chloride is actually quite cheap-cheaper than rice.
but if you're a rice eater, you most likely already have some. If you don't need calcium chloride for anything else, that's going to be an extra expense, to end up with far more than you need for a tube of RTV.
Further calcium chloride is corrosive, not what I'd want a metal tube of goop stored in.
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I'd put it in a packet first.
But yes, if one has rice around and one doesn't mind the "aroma" of RTV off gassed rice, certainly can use it and then eat it later. Personally speaking, I'm gonna pass on that one.
But yes, if one has rice around and one doesn't mind the "aroma" of RTV off gassed rice, certainly can use it and then eat it later. Personally speaking, I'm gonna pass on that one.
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Aluminum foil is better because it is completely impermeable to moisture vapor, oxygen, etc. Awhile back, I became interested in making my own vacuum insulated panels. That led me down a long rabbit hole of physics/material properties. I learned that most plastics and rubbers are more permeable to moisture vapor, oxygen, etc. than we typically think/may assume. Few materials are strongly to completely impermeable (especially under vacuum). Aluminum, certain stainless steel alloys, and glass are a relative few that are impermeable.
Even those regular Food Saver type bags allow some slow gaseous exchange over time (they are helped by often being put in a freezer which further slows down that process). The ones with the aluminum liners are the best for longest term preservation (but even those aren't perfect as there are some gaps between the different layers).
I triple wrap my silicone RTV in zip-top sandwich bags, trying to squeeze out as much air as I can. Seems to keep it fresh for a long time. Nothing is perfect, but 3 baggies are cheap and easy. Yes, aluminized film would be rather less permeable than plain polyethylene, but I don't have any of that.
You can get anti-static bags pretty cheaply (like from McMaster) that look like they seal against moisture better than sandwich bags. Electronic components are moisture sensitive during the soldering process, so need to be dry.
You can get anti-static bags pretty cheaply (like from McMaster) that look like they seal against moisture better than sandwich bags. Electronic components are moisture sensitive during the soldering process, so need to be dry.
For one data point, I just opened up a tube that had been triple wrapped in sandwich bags for 3 years, and it's still good. There was a little dried plug at the opening, but the rest is still fine.
I used what I wanted to and wrapped it back up for next time.
I used what I wanted to and wrapped it back up for next time.
Has anyone had success following the instructions in the Permatex TDS? My tubes always cure beyond the nozzle/tip and I'm not able to use the rest of the product without cutting it open.
https://www.permatex.com/products/a...ex-clear-rtv-silicone-adhesive-sealant-3-oz/#
https://www.permatex.com/products/a...ex-clear-rtv-silicone-adhesive-sealant-3-oz/#
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