I'm a Swedish writer and aikido instructor, 6 dan Aikikai Shihan, former Vice Chairman of the International Aikido Federation. I've practiced aikido since 1972. I also teach the sword art iaido. Here's my budo bio.
by Stefan Stenudd. The aikibatto sword and staff exercises for aikido students explained, with practical and spiritual aspects of the sword arts, equipment for training, and more. Click the image to see the book at Amazon.
Increase your life energy, by Stefan Stenudd. The life energy qi (also chi or ki), with exercises on how to awaken, increase, and use it. Click the image to see the book at Amazon.
Ikkyo in Tantodori
The Aikido Technique Ikkyo on Tsuki Knife Attack
When taking the knife from the attacker in the ikkyo technique, it is very important firstly to press uke's arm to the floor and hold it firmly. The arm should be straight and at least 90° from uke's body, with the elbow pointing upward or even a bit forward.
All of the above is to fix uke's arm at this position and keep it there.
When this is done satisfactory, not before, use your free hand to adjust the position of uke's knife hand, according to the photo above. Watch the knife carefully - how it is held by uke and in what direction the edge of it is pointing.
In the case of a tsuki attack the knife should normally be positioned as on these pictures, but it is not certain. If the attack had been done from a knife grip where the edge of it was initially upward, it would be in a reverse position here, and removing it would have to be done slightly differently from what is shown below.
The knife here is single-edge, which is more easy to handle than a double edge one. This too must be carefully observed before taking it from uke.
Now it is time to take the knife. Form your hand into a fork shape, like the letter U, as shown on the picture above. Do not bend your fingers, neither the thumb nor the others. This shape of the hand should be kept until the knife is safely removed from uke's grip.
Move your hand in a semi-circle, allowing the backside of the knife blade to press against the bottom of the U, that is the area between the thumb and the index finger.
The back of your hand should slide on the floor, not move up the least from it, or the angle will become much less efficient for releasing the knife from uke's grip. The semi-circle should be done with uke's hand as the center - fixed at the same spot all through.
Never try to pull the knife away, before completing this semi-circle, even if uke's grip seems to be loosening. The knife will surely break free at the end of this movement, if not before, when pointing toward uke's head and the edge almost touching uke's arm.
Apply a good grip on the knife, before moving away from your position or releasing uke's arm.
Video clips: In January 2006 I have added some video clips of tantodori ikkyo, which can be found here: tantodori ikkyo
My Aikido Books
Basic Concepts of the Peaceful Martial Art, by Stefan Stenudd. Aikido principles, philosophy, and basic ideas. Click the image to see the book at Amazon.
How to do kogeki, the attack techniques, by Stefan Stenudd. All the attack techniques in aikido explained, and how to do them correctly. Click the image to see the book at Amazon.