Split the 8 coins into 2 groups of 4 coins each.

1 of the groups carrying the fake coin will tilt the scales down.

now take the remaining 4 coins and again split them into 2 groups of 2

Now one of the 2 scales will tilt downwards again. This time take the topmost coin on either sides of the scale and on observation we can get the following possibilities.

1. The scale remains level ====> the coin taken from the downward tilted scale pan is the fake coin

2. The scale remains tilted ====> the coin left on the downward titled pan is the fake coin.

P.S. Strictly speaking the last part is a third weighing, hoping to see better answer from the community here !!!