Why oh why does the sealant in sealing guns go off, even when you've taken great care to ensure it is air tight, more over is there a solution to this problem?
Nothing much you can do, they have a shelf life. Just try and use as much as possible in a short space of time, or look for smaller tubes. Sometimes you can use some that hasn't gone off by cutting open the tube, often some in the centre is still useable.
I find with silicone the best thing is to squeeze a small "tail" out of the nozzle when I am finished - about 10mm. This cures along with a little inside the nozzle and when I next want to use it I can pull all the cured stuff out with the tail - pull gently.
In my experience this is much better than cling film or screws etc put into the nozzle.
If the worst comes to the worst I can unscrew the nozzle and replace it with a new one - the stuff in the tube is usually still uncured.
However I have found no way to save polyurethane sealant. Does the freezer help for it?
They cure by reaction with moisture in the air so the better you prevent contact with moist air the longer they keep. Smaller tubes may be a false economy because they cost nearly as much as the cartridges.
Silicone, by the way. Silicon is a hard brittle non-metallic element unsuitable as a sealant and very uncomfortable as a breast implant!
<P ID="edit"><FONT SIZE=-1>Edited by VicS on 27/11/2002 20:27 (server time).</FONT></P>