I've attempted using BodyVelocity and still haven't got any luck.
COMMUNITY QUESTION
How do I make a brick or model bob up and down?
1 answer
If attemping to use CFrame, try using math.sin (in a for loop, or variable). Wiki here.
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2 comments
BodyForce or CFrame?
You have the option of bodyforce or of CFrame. If you want it better, use bodyforce. Have a script to increase and decrease the y axis of the bodyforce.