Knocking in: Why we do it.
Almost all new cricket bats require knocking in before use. Knocking in is the process of hardening and conditioning the surface of the blade and there are two reasons for knocking in;
- To protect the bat from cracking and therefore increase its usable life
- To improve the middle of the bat so the middle is bigger and better
Just in case you did not know, the nature of the game of cricket is that a hard ball is propelled at high speed towards the batsman who swings a wooden bat aiming to hit the ball. This intense contact will cause a bat that is not prepared correctly to crack up very quickly, therefore having a very short life.
Cricket bats are pressed in the bat making workshop using a mechanical press. The mechanical press applies up to 2tons/square inch of pressure to the face of the bat through a roller. Willow is a very soft timber in its natural state and it has to be pressed so 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. While 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 as with a bat pressed lightly and knocked in by hand.
Heavily pressed bats do not break so some firms over press bats to keep their warrantee work down. This ruins the middle of the bat and the ball does 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.
At the stage when the bat is purchased there are different ways of preparing it for the knocking in process. I recommend the following process as repeated trials in bat workshops have shown me that it works far better than other methods.
Raw linseed oil should be used to moisten the surface of the bat and enable the fibres to become supple and knit together therefore forming an elastic surface. This is more likely to stretch on impact, rather than crack. Raw linseed is used due to the fact that it stays moist for longer than boiled linseed. About a teaspoonful should be applied to the surface of the bat.
I recommend that oil should be applied 3 times before the process of compressing the face begins. Each coat of oil should be about a teaspoon full which should be 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.
When the three coats of oil have been applied the knocking in process can begin. This should be done using a Hardwood bat mallet as these provide much better performance than a ball mallet, and therefore speed up the process.
Start by hitting the middle of the bat just hard enough to create a dent (this is surprisingly hard) and hold the bat up to the light to check if you are making a dent. Gradually compress the face of the bat around this dent so the face of the bat is level and you cannot see the initial dent any more.
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 knocking in 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.
If the bat edge is hit at 90 degrees to the face it reduces the width of the bat and is covering an area that is not mechanically pressed. The likelihood of cracking increases 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 from between 10 to 15 sessions of about 10 minutes each. Once you have completed this process take the bat into the nets and play a few shots against an old ball. If the bat is showing very deep seam marks to the point of almost cracking the face of the bat then it needs more compressing. One will always get seam marks on the face of the bat but they should not be too deep.
The price of a bat does not have any effect on whether a bat cracks or not.
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 performance out of it. As an example, 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.
At Laver & Wood we strongly recommend to have your bat knocked in professionally when you purchase it. This helps to get a better performance and generally extends the life of the bat. It also relieves you and your family members of a time consuming, noisy and monotonous process. Ask at your local cricket dealer if they can have your bat knocked in by a bat-maker – it should not cost too much at all and is certainly a worthwhile investment.
It is worth noting that 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 should last for about a thousand runs.
Laver & Wood offer a full hand knocking in service.