Let the machine spot you and build to full bodyweight dips.
More assist weight makes it easier, so drop the assistance over time as you get stronger.
The assisted dip hands you the full dip, upright torso, deep elbow bend, hard triceps lockout, while the machine's pad offsets enough bodyweight to keep every rep clean. The triceps lead the press, with the chest and shoulders assisting out of the bottom position. Reduce the assistance over time and this converts directly into unassisted dips.
Lower until your elbows hit around ninety degrees, then press to full lockout. Because the machine strips away the balance demand, this is the perfect place to groove that depth under control before going unassisted.
The stack is a counterweight, it pushes the pad up underneath you. More weight means more of your body is being carried for you. To make the exercise harder, take weight off the stack.
Drop the assistance a small step whenever you top your rep range, and finish sets with slow lowers on the machine. When you are down to minimal assistance for solid reps, test a few bodyweight dips at the start of a fresh session.
