I can't emphasize enough how dangerous knives can be on the body....but there are some ways to use them in a manner that can be safe....and it will take a lot of control on your part as a top.
Key Items: Keep your knives clean. Sterilize if you can. Clean the body you will use it on: Use an anti-microbial....alcohol minimal. Clean the body surface after play. Clean the knives after play.
1. Know Your Knife....the weight of it in your hand holding it by the handle, the sharpness of the blade (single or dual), if it can cut and how easily.
2. Test It ....on paper before you test it on skin. See how to drag the sharp and dull edge...what it does.
3. Learn to Control the Pressure on the Tip (opposite the handle)....but how you position the angle of it. Hold the handle with the blade down....tip lower than the handle level. Place the tip on paper. If you lower the handle closer to the paper....the impact down is not so much. If you raise the handle....the pressure on the tip increases.
4. Learn First Aid....because if your knife cuts....you'll need to know how to close a wound, to clean it, what meds to use, and bandage it. Have a bit of common sense and decency to not use a knife in a manner you can't handle.
5. Not Just the Edge of the Blade....using a knife on the body isn't just about running the blade or tip of the knife on the body. It's also about using an the length of an edge at an angle (in reference to the opposite side of the blade) to scrap on the body surface. How you angle that edge will determine the pressure on it. Higher up the angle....more pressure. Lower...less pressure. And you can scrap with either the sharp edge or dull. Run it carefully. Look at what you are doing. Be ready if the bottom jerks so you can quickly move the knife off the body.
6. Sharp Blade Down on the Body....yes, you can put the sharp edge of the blade down (length) on the body surface as long as you know just how sharp it is. The skin is quite resistant...more than you might realize. Light pressure at first. Harder pressure, but not too much....and only if the sharp edge is slightly dull....NOT razor sharp. Hold the blade firmly on the skin with palm flat over dull edge as you push down. Backsides work best for this. DO NOT DRAG or SCRAP when doing this or the knife will cut.
