The 20-year-old left back becomes our sixth summer signing, and has agreed a two-year deal in E10.
Born in Hertfordshire, Scales started out at Norwich City’s Academy before attracting the interest of Crystal Palace, and in 2014 made the switch to South London.
The defender was rewarded for an impressive first year with the Eagles, and signed his first professional contract in April 2015 before gaining his first taste of first team football when joining Crawley Town on loan at the start of the 2015-16 season.
Scales made his Football League debut for Crawley at Cambridge United on August 22, 2015, helping the Red Devils come away from the Abbey Stadium with a 3-0 victory.
Following the conclusion of the 2015-16 season however, Scales departed Crystal Palace and spent the second half of last season with National League South side Whitehawk.