Moulders are used for 4 face sizing, planing and/or moulding of rough lumber stock. There are two main types of moulders. Through-feed moulders have become generally more popular in the secondary wood industries as they have better straightening capabilities and they also "through-feed" the boards out of the machine at jobs end eliminating the need for a pusher board. Due to their straightening capabilities they also generally require more oversize of the rough boards. Push-feed moulders are fed from the in-feed end. Boards are butt fed and pushed through the machine. Push-feed machines are used more for construction grade lumber, where straightening is less important. Moulders generally have from 4 to 6 machining spindles, both vertical and horizontal, however some machines have additional heads for specific requirements. Set-up of moulders ranges from fully manual to fully automated.