1. What is a recess? A recess is a groove on the inner wall of the yoyo that
goes around the bearing seat area. A recess is used to hold the response
for the yoyo, whether a pad, an o-ring, or silicone.
2. When recessing, I have noticed that certain yoyos may APPEAR to have an
incredibly thin wall. However, in some cases, what looks this way, may not
be true. For example I recessed a Yomega Stealth Raider to take an o-ring,
without going through the wall.
3. To tell how deep you are on a recess, periodicly stop cutting and screw the
yoyo together. Grabbing by the rims, try to see if you can bend the yoyos
hub (if you push in and out at the rims, and the yoyo remains strong, you
haven't gone too deep). If you do however go to deep, your yoyo may break
if it comes in contact with the floor (oops, personal experience).
4. If you are planning on a first time recess, here's a helpful tip for keeping it even:
Don't cut with a whole saw; the yoyo should be spinning, not the cutting tool.
That way it will make a perfect circle if your dremel, drill, drill press, or lathe is
secure. Secure the yoyo by the axle in the chuck of the power tool (unless using
a lathe), then secure the dremel/drill in a vice to keep it from shaking around.
Then slowly cut into it with a corkscrew, chisel, etc. Hope this helps.