Throw a taller cylinder (500 g, ~15 cm)

This is where it gets serious. 15 cm from 500 g with 5 mm walls means you need efficient pulls and good clay management.

Strategy

• You'll likely need 3–4 pulls
• Leave a bit of extra thickness at the base (gravity wants to slump the top)
• Correct wobbles early; they only get worse
• Keep the cylinder straight; flaring out wastes height

Success looks like

• ~15 cm tall, straight walls
• 5 mm walls top to bottom
• No wobble at any wheel speed
• Clean, compressed rim

If it collapses on pull 3 or 4, your walls are probably uneven. Focus on consistent pressure next time.