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Super glue (ethyl cyanoacrylate) is marvellous stuff when used on a recent break, anything that hasn't had time to gather dirt, grit or grease, and where there are no gaps to fill. However, it is possible to deal with some seemingly impossible repairs by mixing other materials with the base product.
Wood, for example, is a suitable material for this practice, using very fine sawdust as the powder mix. Wood is an absorbent material, so glue is normally absorbed, and breaks with gaps, chips, gouges, etc. create a weakness in the repair. The addition of a powdery substance, like sawdust in this instance, provides a medium to fill the gaps and enhance the quality of the bond.
The suitability of this method for other materials depends on whether there is an ideal powdery substance available to mend the break. A degree of cautious experimentation is recommended to see if this method can be practically applied to materials you may be working with.
The following procedure should be followed, using common sense to manage any unexpected developments:
Secure the item to be repaired, ideally using something other than fingers. Fingers and super glue are a less than perfect partnership. Use a vice, clamps, clothes pegs, rubber bands, etc.
Take the glue container and apply enough glue for the required repair (follow guidelines on, or supplied with, the container).
Sprinkle the powder on to the glue and leave for a few seconds, then blow off the excess.
If necessary, push any remaining glue/powder mix into the repair (again, fingers are not recommended - use a stick, pin, pencil - something that you don't mind getting a little glue on).
Allow the repair to cure for as long as possible. Wood, for example, will normally bond in a few minutes, but it may take substantially longer for the glue to harden completely.
The resulting material is extremely hard, but can be sanded down manually with some effort, or by using an electric sander. In the same way, you can use strips of cloth, or other absorbent material to affect a reinforced repair.
Disclaimer and Precautions
Note that this is not a manufacturer-recommended practice, but a presentation of findings based on experience. You should always read instructions accompanying an adhesive carefully before use to ensure safety and a reasonable chance of success in using the product. The reaction of glues with other materials, as described above, may create heat and fumes that could be harmful unless precautions are taken and the work is completed in a well-ventilated space.