The arms are open to different media. Here are a selection of pics of the types of materials I use on my dummy.
[Example 1 out of 6]
First pic is of some arms I picked up recently with glossy wooden arms. These are lovely to work with and are now my first choice. They make a lovely clacking noise, very crisp. And the wood is slightly lighter than my other beechwood arms, which creates a different feel. The offset nature of the back end of the arm is more pronounced, too.
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< A silencer! If you are up in the very early morning, or late at night and do not want those clacking noises then the rubbery edge connectors of those child play mats can be slotted in.
These 'give' a little when pressed and offer a different feeling.
Should have thought of this years ago. A pick axe handle offers something new. Distance.
(Some people think this is heresy, as you are fooling with tradition. I say Bruce Lee led the way - and that happened any way when the Pole was added to the Wing Chun inventory).
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This picture shows a yoga mat plus inner tube. It is different. Now the softer inner tube adds something to the mat alone. The tube also stops the mat unravelling, as I have not cut squares into it like the YouTube suggestion below.
I suspect sharper readers of this blog will see an uncanny resemblance to the Emperor Dalek below from Dr.Who. ;>