MTFCA Forum

When a sealant (Ultra Black, RTV, etc) comes in large and small sizes, from now on I'll get the small size. If I buy a large size and use only part of it, the remainder will be useless by the time I need it. If you infer from this that I just tried to use a previously opened large tube, you're right.

I wonder how many tubes I have poked holes in to get to the good stuff. With a few exceptions, that is why I went back to Permatex No 2. Does not seem to have the same issues. Like I told Mom, that is why I buy small jars of some things that I don't use often, I would rather pay a little more per Oz and toss a small empty jar then toss a big 1/2 full jar after it expires.

I buy big tubes and they last until I get the last smidgen out. I have a lot of powder coating done, so I have these silicone plugs of many different sizes. Insert one of these small ones into the end of an open tube, and it’ll never get air to it to go off. I push them in easily about an inch.

One thing that helps slow the sealant from sealing the tube opening is to use the long pointed applicator that comes with the tube, making sure it is on tight, clip the end open. Then squeeze the sealant until the applicator is full and a half inch or so is squirting out the end. Set the whole thing aside and let that bit dry and seal the end of the applicator. When you are ready to use more, pull the tip piece off. If it is dry in the applicator, remove it from the tube, and as long as the tube still squeezes out, just take a thin screwdriver or punch and push out the dried plug in the applicator and there you go. Repeat as you need. The main thing is to keep the joint at the tube sealed so no air/moisture get to the end of the tube opening. Another thing to consider is where you are buying the sealant- do they sell enough to keep fresh stock in? The sealant has a shelf life, and can be starting to dry up before you even get it if the stuff has been on the shelf too long!

What is strange is I have a tube of GE RTV that my father got when he was working for a company that built targets for the Army Red Eye missile. You old Army guys know when that was!
It is still good. I wonder if the new stuff is made to “harden” in a certain time? I always get a big puff of air out of the new stuff about half way down the tube. Dan

Last time I shopped, Bill, most sealants don’t even come with that long extension tube any longer. I say K.I.S.S. , this works well for me. If anyone needs some silicone plugs, just ask on your next purchase, I’ll throw them in. As you can see, I get every morsel outa the tube!

I have a "trick" that has worked very well for me.

First, I am very careful to make sure I keep the original cap and do not damage it. Most times, the cap will get threaded on too tight and will crack, thus allowing the RTV to contact the air. I make sure to seal the cap but NOT over-tighten it. Second, I make sure to enclose the tube in a freezer-grade zip-top bag. I put the tube in the bottom of the bag, then roll the bag around the tube to expel all the air I can get out. Seal the top and put it in a secure location. I have been able to return several months later and the RTV is still in perfect shape. As crazy as this sounds, I have had tubes last for years until I used them up.

Being as RTV is air vulcanized (cured), excluding the air from the RTV will make it last. I have considered putting some argon gas or carbon dioxide in the bag to displace the oxygen but haven't tried that yet. I told a friend about my trick and he made a different suggestion along the same idea line: Use a condom on top of the tube to seal out the air. I still don't know if he was serious or just yanking my chain.

Remember, the manufacturer puts the goop in an air-tight tube to make it last until you purchase it. If you can exclude the air from an opened tube, it should last long enough for you to use it all, big tube or little tube. I have done the same with tubes of caulking. Works very well there also.

Good Luck,
Terry

Terry, just be sure to use a reservoir tipped condom, so as to be able to put the tube tip in the reservoir! Should be air tight there for sure!

Tim, GOOD ONE!!!!!

I hadn't thought about which type would be best to use. Pretty sure you got that one on the head.
Would you re-use it?

What works for me is making a little blob at the top, I then pull the finger off a latex/nitrile glove and put it over the top and secure it with a cable tie. Lasts for months

Terry....oh nooooo.....NEVER!!

Quit often the sealed area is only at the original opening.

You can punch a hole in the other end and squeeze out what you need, then roll it up a turn and do it a few more times to use all the stuff.

I do as Jim says except I use side cutters to nip the side of the tube near the bottom. The next time I nip it again in another, nearby spot.

I seal silicone sealant and similar tubes with a drop of hot melt glue after cleaning the end of the tube. I just peel it off and start work when I need it, and re-apply another drop when I'm done.