This article is from the RSC/UKSC Cricket FAQ, by Ganesh with numerous contributions by others.
The basic idea is to avoid splinters and bits breaking off
the edges by gently tapping the bat with a mallet. Really
need advice on knocking? Then read on. Otherwise skip the
following excellent advise.
Cameron Fraser:
When you buy a bat, it is only lightly pressed at the
factory and the fibres are still really soft - if you
press your fingernail into the surface you'll see what
I mean. 'Knocking in' is the process of compressing and
binding these lose fibres together to allow the bat to
withstand the constant impact from the ball. You're
preparing the bat to be HIT.Your aim is to 'bash' the
surface of the blade - not the back or the bottom of
the bat (that can be disastrous!) You can use an OLD,
GOOD QUALITY ball in your hand or put it in a sock or
try different types of 'knocking in' mallets - my
preference is for the solid wood version. Any good shop
or mail order company does them for around a fiver -
buy one, you'll need to make use of it many times.
Start 'knocking in' by gently working on the edges and
gradually knocking them into a rounded, compressed shape
once you get started you'll soon see the change in
texture. Then keep working on the edges and the area
around the toe of the bat - not the bottom of the bat -
and think of trying to use glancing strokes that resemble
you edging a ball to gully, then 3rd slip, 2nd slip, etc.
while all the time gradually increasing the strength of
the impact.Don't forget to give the middle a good going
over but the priority should be the outside inch or so
of the bat round both edges and the toe.
How long do you have to go through this mind numbingly
boring routine? Slazenger recommend 6 hours - now that
is a long, long time. If you try to do it in good 5
minute blocks it becomes more manageable. Essentially
you don't want to think about using the bat until it's
had at least 2 hours(24 x 5 minute sessions) but ideally
if you can manage double that then all the better. If you
have the time and space and tolerant neighbours then the
process can be done in a week or so - most of us need a bit
longer! But there's no point going to the other extreme -
buying a bat one season and not using it until the next.
Anyway, such self-denial would be way beyond the likes
of me or most cricketers I know! So use the bat but be
sensible.
After the initial 2-4 hours 'knocking in,' try using it
for hitting short catches and then in the nets against
OLD, GOOD QUALITY balls and only against the spinners/
slow mediums first. A new or cheap ball can do a lot of
damage to an under-prepared bat and digging out a fast
yorker in the nets can spell doom and destruction for
even the best prepared bat! So try and middle the ball
and play the bat in - resist the wild slogging for once!
Then do some more 'knocking in' and then some more and
then some more and then some more...
Remember, SOME bats need a LITTLE linseed oil - but no
more than a couple of teaspoonfuls per season! However,
ALL BATS NEED KNOCKING IN. Gunn & Moore now provide this
service for around 10 pounds in their GM NOW range. For
most people that's 10 lbs well spent. But don't forget you'll
still need to keep 'knocking in' throughout the life of
your bat, knocking out indentations, evening out dead
spots in the bat, strengthening area around glued repairs
etc. A cricket dealer I know recommends that the day you
stop 'knocking in' is the day you throw the bat in the
bin.
 
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