What It Is
The butterfly swords, known in Cantonese as Baat Jaam Dao (eight cutting knives), are a pair of short, broad blades used in Wing Chun's double-weapon form. The form extends the empty-hand techniques into blade work, training precise wrist control, strong footwork and constant attention to the centreline. It is traditionally one of the advanced forms of the system.
Why the Swords Come Late
The butterfly sword form is built on the hand shapes, stances and footwork of the empty-hand forms. Many of its movements are direct extensions of Tan Sao, Bong Sao and Gaun Sao, with the blade simply continuing the line of the forearm. Without those foundations, the swords are just two pieces of metal moving in the air.
That is why the form appears late in the curriculum: it doesn't introduce new principles so much as test whether the old ones are truly in place.
What It Trains
Wrist strength and control, because each blade has to stay on its line without wobbling. Footwork, because the swords demand more stepping and angling than any empty-hand form. And timing, because two weapons moving at once leave no room for one hand to drift.
How to Practise Safely
Begin with wooden or blunt training swords. Learn each section slowly until the blades travel the same path every time, then add speed. Practise in a space with plenty of room, and keep the blades' edges and points aware of your own body during every transition.
Common Mistakes
Swinging from the shoulder rather than the elbow and wrist. Letting the footwork lag behind the blades. And chasing speed before the lines are clean, which makes the form look impressive and teaches nothing.
Can you learn the butterfly swords online?
Yes. The butterfly swords is taught step by step in Kung Fu Kendra’s Wing Chun Online Certification Course, a 10-level program taught by 3rd generation Ip Man lineage master Sifu Kendra Mahon (Grandmaster William Cheung, 1st generation; Master Brian Lewadny, 2nd generation). Every level has a graded exam, students get direct feedback, and it is a single one-time fee with no monthly payments.
Kendra’s Verdict
The butterfly swords are where you find out whether your Wing Chun is really built on structure. Earn them, then train them carefully.