This page came about from two threads on the Old Tools:
It is proper to say, “can o’ nibs”, “can-o-nibs”, “can’o'nibs”, “can of nibs”, or “can-of-nibs”. Actually, say it any way you want, it’s not like there’s a galoot-o-pedia for someone to correct you by (actually there is: galootopedia.com).
The idea behind this page is to capture theories on lore-like issues that can never seem to be answered, or are answered but still argued over. The first will be nibs, others to be added as seen fit.
Many of the reasons why the nib is there:
The nib is for launching rubber bands at people trying to steal the trade by watching the craftsman. – Cliff Rohrabacher Esq.
For tying a tooth-guard to the saw, one string can wrap around the handle, but the nib is to keep the guard on the toe. The reason Disston made the skew-back was to discourage tooth-guards, thus making more money for saw filers and himself. Remember he was part of the Cabal.
A nib can be used to start a cut rather than a backstroke or a couple of light strokes. This is why so many nibs are found very sharp.
It can also be used for scribing a line. Once again, why nibs are always sharp. You need a cant-back-this-up file to sharpen it correctly.
Apparently, some manufacturers used the nib as a jig or alignment point. That’s why saws with nibs are very consistent in size and form. Disston realized that by getting rid of the nib, it would show they weren’t lazy like the other manufacturers.
The nib was used to test the tension of a saw, providing a tab to make the saw ‘sing’. Buyers could check the quality of a saw before purchasing with this feature. Apparently all the saws I’ve tested in this matter are of poor quality, purchased and passed on by some poor sap who didn’t know the secret. Either that or I’m def.
Other anecdotes associated with nibs:
Whilst pondering a ‘whatsit’ pictured here, “It’s a nib set. Hard to use properly, broke off a lot of nibs.” -Steve Jones
English Polish is applied by an Englishman, French Polish by a Frenchman. Americans use polyurethane so it doesn’t matter what we call it. Polish Polish is applied by a Pole or a Polisher depending on context.
An excellent thread from the Porch on flattening honing stones.