Slicone Tube With Clogged Nozzle

Again my tube of silicone is cured in the tip and it's clogged. wtf? It's the GE Silicone II in the 300ml tube..

I've tried the plastic cap that comes with the tube... I've tried screwing a screw in the nozzle. I've tried aluminum foil and then put the cap on. But noooo...it's still cures and clogs up the nozzle...

Being very annoyed and impatient, I just hacked off the whole nozzle for extra assurance.. A conical shaped clog in a conical nozzle is excellent to prevent a clog from escaping..

One time I had ended up sawing a tube in half just to get ahead of the cured portion.

I might try a custom tight fitting rubber cap for the nozzle.. ^*&$$% !

D from BC

Reply to
D from BC
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What i found that helps, is to put a nail in the nozzle; diameter close to same as ID of nozzle, and nice flat head. Then put that cap on. Makes it last longer, and if it partly solidifies inside, pulling the nail out clears most of the nozzle.

Failing that, you would need a moisture tight seal at the nozzle opening; that might work longer.

Reply to
Robert Baer

Since moisture (and perhaps also higher temperatures) cause curing, perhaps sealing the entire tube tightly in a plastic bag, and then storing it in the refrigerator, may help prolong its shelf life.

Paul

Reply to
Paul E. Schoen

Having over time used hundreds of tubes of the stuff I know the nozzle will -always- be clogged. So before use I unscrew it and poke a screwdriver down the nozzle in the reverse direction, until the cured slug comes out. (messy but quick)

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Reply to
john jardine

Once that plastic nozzle is snipped at the tip...it's all downhill and it clogs even when capped after use.

I suspect that even with the provided cap for the nozzle, there are still microscopic leaks and the silicone cures. Also, I think there's very little release required for cure to happen. The molecules slip out somewhere.

However.... I have a metal squishy tube of car silicone gasket material with a screw cap with many fine threads.. I've had it for 4 years... Never clogged.. Cures in 24hrs. But noooo... many 300mL silicone tubes found at the hardware store come with crappy pop on caps that don't seem to work at preventing cure in the nozzle. I think it's a conspiracy to sell silicone!! :) Or perhaps the good way has been patented and nobody wants to pay.. :) D from BC

Reply to
D from BC

Well I have a way that keeps it fresh for a little longer, but not indefinitely. I soak a piece of paper towel in tap water, wring it out, then stuff it into the cap. Press the cap on until it clicks, and the damp paper seems to keep the silicon from drying out for a while. If you cannot get the cap back on, then you have used too much paper towel.

- Tim -

Reply to
Tim

I guess the trick is to keep oxygen out of the product. Once the nozzle's been clipped, it's hard to accomplish this with anthing that's only a friction fit.

Maybe resealing the nozzle tip with a hot glue gun would work.

Reply to
Greg Neill

Similarly, I use a screw that fits snugly into the clipped end of the tube.

Reply to
Richard Henry

Threading a bolt down the inside of the nozzle works pretty well--the cured stuff comes out with the bolt.

Cheers,

Phil Hobbs

Reply to
Phil Hobbs

RTV silicone is water-catalyzed; British Columbia is reputed to be a non-dry environment.

It is possible to buy a paint can and some CaSO4 dessicant to store RTV (and it is a good idea for cyanoacrylate SuperGlue as well). I've had clogs that required carving open the tube, and after months in the dessicant-paint-can the RTV was still fresh.

--- whit in Seattle (not having a drought here, either)

Reply to
whit3rd

That makes absolutely no sense. Silicone cures by hydrolysis -- H2O displaces acetic acid, which is why it has that distinctive smell as it dries. Oxygen doesn't come into the picture, this isn't linseed oil.

Tim

-- "Librarians are hiding something." - Steven Colbert Website @

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Reply to
Tim Williams

How about priotirizing properly, when doing "work"(!?) prepare a dozen fresh tubes. But if you engage in cleaning clogged tips that IS a 'hobby' so enjoy.

In mid '60's Kodak rep. did his song and dance about the 910 glue (the cyanoacrilic stuff) that glues _everything_ stronger than 'whatever' till someone asked how do you open the container. Try asking Kodak maybe they still remember this secret.

HTH

Stanislaw

Reply to
Stanislaw Flatto

Try squeezing a bit of silicone into the cap before replacing the cap. Dan

Reply to
Daniel A. Thomas

messagenews: snipped-for-privacy@4ax.com...

Dan,you have nailed it.

Reply to
rpang

I did that yesterday after I hack saw'd off the whole nozzle...(right up to the tube). I cleaned away the silicone around the opening and then pumped hot glue gun in and around the opening... I'll find out in a few months if it works. My guess is that the glue gun glue will have poor adhesion to the plastic tube (polyethylene??) It might peel and leak the silicone release chemicals causing cure, clogs and wasted silicone. D from BC

Reply to
D from BC

Cool :) I like that water absorbing chemical idea... I''ll try... :) I didn't know how RTV silicone cures..

Some regions in BC are semi-desert. Osoyoos gets about 10in of rain/year and is Canada's only hot desert with over 2000 hours of sunshine per year. Downtown Vancouver BC gets rain for about half a year.. I'm in the wet area..

CaSO4.... IIRC that's the main content in drywall.. interesting... I did some research long ago on it's water breathing properties with temperature.

Heyy...there's an invention...A special cap that removes water vapour at one end and releases it at the other.. mmmmm :) D from BC

Reply to
D from BC

messagenews: snipped-for-privacy@4ax.com...

I've been reluctant to do that because silicone doesn't seal itself off.. This is an attempt at using the silicone to "gasket" itself.. I don't believe cured silicone about the cap will stop curing in the nozzle.. However, I can imagine that it'll slow nozzle cure and it'll be better than an empty leak about the cap.

I've been tempted to find a 2 part silicone for electronics so that I don't have any clogged nozzles..

D from BC

Reply to
D from BC

I've had some problems with screws splitting the tip of the silicone nozzle... Perhaps, I might do a trip to the hardware store to get a matching bolt for the silicone nozzle. D from BC

Reply to
D from BC

The plastic bag idea might be of some help; the refrigerator makes for an excellent source of moisture - not recommended.

Reply to
Robert Baer

It has been my experience that unsealed items in the refrigerator and freezer become dried out. Also, the fact that water vapor is seen to be condensing on cold parts and even frosting up indicates that water vapor is being forced out of the air. Even though the relative humidity inside may actually be greater than outside air, the actual amount of moisture in the cold air is much less. I also thought the cold would slow down the curing rate.

The best idea seems to be the dessicant (silica gel?) in a sealed container with the silicone. Storing the container in the fridge might be one more helpful precaution.

Paul

Reply to
Paul E. Schoen

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