Almost all new cricket bats require knocking in before use. Knocking in is the process of hardening and conditioning the blade’s surface. There are two reasons for knocking in, firstly it protects the bat from cracking, as well as increasing its usable life and secondly improves the middle of the bat so the middle is bigger and better. The nature of the game of cricket is that a hard ball is propelled at high speed toward the batsman who swings the bat in the attempt of hitting the ball. This contact will cause an insufficiently prepared bat to crack very quickly and therefore have a short life span.
Cricket bats are pressed in the bat-making workshop using a mechanical press. The mechanical press applies up to two tons per square inch of pressure to the face of the bat through a roller. Willow, in its natural state, is a very soft timber and has to be pressed to form a hard, resilient layer on the surface. Once this has been done, the bat can be shaped.
The finished bat still needs a final hardening as the mechanical presses are unable to completely protect the bat, or get the perfect performance required from the blade. This requires knocking in by hand with a mallet. Whilst it is possible to prepare a bat solely by pressing, this compresses the wood too deep into the blade which dramatically reduces the performance of the bat. A bat pressed heavily will have a small middle and the ball will not travel as far it would from a bat pressed lightly and knocked in by hand.
Heavily pressed bats do not break so some firms over press bats to keep their warranty work down. This ruins the middle of the bat and the ball will not ‘ping’ off the middle as it should. We occasionally get asked to try to improve the middle of over pressed bats – this is a tricky task and not always successful.
The knocking in process:
There are different ways of preparing your bat for the knocking in process, but we recommend the following process as repeated trials in bat factories have shown us that this works far better than all other methods.
Raw linseed oil should be used to moisten the surface of the bat and enable the fibres to become supple. This helps them knit together, thus forming an elastic surface. This is more likely to stretch on impact, rather than crack. Raw linseed is used, as it stays moist for longer than boiled linseed. About a teaspoonful should be applied to the surface of the bat.
We recommend that oil should be applied once (3 times if not one of our bats) before the process of compressing the face begins. Each coat of oil should be about one teaspoon full. Spread the oil over the face of the bat using your fingers. Spread the leftover linseed oil over the edges and toe of the bat. Let each coat of oil soak in overnight and repeat the process before starting the knocking in with the mallet.
Knock in Face
After the oil has been applied, the knocking in process can begin. This should be done using a Hardwood bat mallet. This provides much better performance than a ball mallet and also speeds up the process.
Start by hitting the middle of the bat just hard enough to create a dent. [This is surprisingly hard]. Hold the bat up to the light to see if you are making a dent.
Knock in Toe
Gradually compress the face of the bat around these dents so that the face of the bat is level and you cannot see the initial dents any more.
The bottom of the bat toe (the part that is in contact with the ground) should never be hit with the mallet!
Knock in edge
The edges require special attention. They need to be rounded off so that the hard new ball cannot damage them too much. The edges should be struck at 45 degrees to the face so that the mallet can compress the willow. Similar to the face make one dent on the edge, and then gradually even out the edge so that the whole surface has a smooth, rounded appearance. The back of the bat should never be touched with the mallet (or the ball).
If the bat is hit on the edge at 90 degrees to the face, it reduces the width of the bat and is making contact with an area that is not mechanically pressed. This increases the likelihood of cracking and you should not be hitting the ball flush on the edge in any case.
With a hardwood bat mallet the knocking in process should take between 10 and 15 sessions of about 10 minutes each (it is probably worth doing this for a bit longer if the bat is of different brand to ours).
Once you have completed this process take the bat into the nets and play a few shots with an old ball. If the bat is showing very deep seam marks then it needs more compressing. One will always get seam marks on the face of the bat; however they should not be too deep.
General knocking in
The price of a bat does not have any effect on whether or not it cracks. The best bats are usually more expensive, but liable to crack more than cheaper bats because the willow is often softer.
Back in the late 1800s the bats were subjected to huge amounts of pressure at the pressing stage to make the willow very hard. If the blade started to show signs of cracking during this process, it was rejected. Linseed oil was very often used to saturate the blade in order to soften the wood, make it more comfortable to use (over pressed bats jar on impact), and get a bit of extra performance out of it. WG Grace would have a few of the junior members of his club using his linseed soaked bats for a season or so before he would deem them ready for use.
When a bat is pressed very hard, it is very difficult to hit the ball off the square. The thin protective layer of hard (pressed) willow becomes a thick layer that is too deep into the willow. Hard-pressed willow does not have the desired elastic qualities of the soft pressed willow, meaning the ball does not ‘ping’ off the bat. Some manufacturers over press their bats, as the harder wood does not crack as readily, reducing the need for warranty work. Their bats, however, have very small middles.
At L&W, we strongly recommend having your bat knocked in professionally when you purchase it. This helps get a better performance and also helps extend the life of the bat. It also relieves you and your family members of a time consuming, noisy and monotonous process.
Please Note: Damage can never be totally eliminated due to the hard nature of the ball and the speed of contact with the bat. A good bat correctly knocked in ideally would last about 1000 runs including net use.
Laver & Wood sell hardwood knocking in mallets and also offer a knocking in service.