Bits and Pieces
Builders' Tip - Superglue and Baking Soda
A typical superglue product
We're all familiar with superglue, which is chiefly composed of cyanoacrylate. You probably know that it sets in the presence of moisture. Typically there is a small amount of humidity on the surfaces to be glued, and it sets from the outside in. If you've ever tried to use it on nonsmooth surfaces, you will have noticed that it doesn't do so well. This is mainly because the inside of the bead of glue doesn't get the humidity immediately.Besides water, cyanoacrylate also polymerises in the presence of alcohol and basic compounds (including weak amines). The latter can be used to produce a superglue "kicker" - a compound which triggers quick polymerisation of the glue.
Baking soda is one well-known accelerator. If you apply a layer of superglue to a seam and gently pour baking soda over it, the glue will cure very quickly. It makes for a most effective filler for smaller jobs, and the rough surface caused by the baking soda is good for sanding. It also won't shrink like most solvent-based fillers you can buy.
It's better to build up thin layers when using an accelerator because of the same slower reaction times with larger recesses when using superglue accelerated with baking soda.
You can also use this technique to mould small parts, if you need something for a hobby.
Superglue is also very handy to temporarily glue a washer to a nut, or two washers together, when trying to insert both into an inaccessible recess.
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