A folding tent frame component comprising: a) a peak bracket and a chord, or a chord knee bracket and a chord, pivotally attached for relative rotation about a first axis of rotation located in said peak bracket or chord knee bracket, between an open position capable of forming part of an erected tent frame and a closed folded position, said chord comprising a first end proximate said first axis of rotation; b) a sliding locking frame slideably movable in said chord, said sliding locking frame comprising a locking pin secured thereto and a lock-out bar pivotally mounted thereon and extending therefrom, c) a first spring arranged to bias said sliding locking frame towards said first end of said chord and a second spring arranged to bias said lock-out bar away from said sliding locking frame to an upward position; wherein said peak bracket or chord knee bracket comprises a pin-receiving slot with a closed end in the direction towards said axis of rotation and open in the opposite direction away from said axis of rotation arranged to reversibly receive said locking pin when said peak bracket or chord knee bracket and said chord are in said open position, and a slot (50, 52) arranged to reversibly receive a head of said lockout bar when said sliding locking frame is moved away from said axis of rotation to withdraw said locking pin from said pin-receiving slot; whereby when said locking pin is received in said pin-receiving slot said peak bracket or chord knee bracket and chord are locked in said open position in the absence of other forces on said sliding locking frame, and when said sliding locking frame is moved away from said axis of rotation to withdraw said locking pin from said pin-receiving slot, said head of said lock-out bar moves into said opening arranged to reversibly receive a portion of said lockout bar to thereby prevent said sliding locking frame from moving back towards said axis of rotation to again lock said peak bracket or chord knee bracket and chord in said open position, and when said portion of said lock-out bar is received in said slot (50, 52) to reversibly receive a portion of said lockout bar said peak bracket or chord knee bracket and chord can be rotated to said second closed folded position; and whereby when said peak bracket or chord knee bracket and chord are rotated back to said open position said locking pin is moved back into said pin-receiving slot by said first spring to thereby again lock said peak bracket or chord knee bracket and chord in said open position. a) a peak bracket and a chord, or a chord knee bracket and a chord, pivotally attached for relative rotation about a first axis of rotation located in said peak bracket or chord knee bracket, between an open position capable of forming part of an erected tent frame and a closed folded position, said chord comprising a first end proximate said first axis of rotation; b) a sliding locking frame slideably movable in said chord, said sliding locking frame comprising a locking pin secured thereto and a lock-out bar pivotally mounted thereon and extending therefrom, c) a first spring arranged to bias said sliding locking frame towards said first end of said chord and a second spring arranged to bias said lock-out bar away from said sliding locking frame to an upward position; wherein said peak bracket or chord knee bracket comprises a pin-receiving slot with a closed end in the direction towards said axis of rotation and open in the opposite direction away from said axis of rotation arranged to reversibly receive said locking pin when said peak bracket or chord knee bracket and said chord are in said open position, and a slot (50, 52) arranged to reversibly receive a head of said lockout bar when said sliding locking frame is moved away from said axis of rotation to withdraw said locking pin from said pin-receiving slot; whereby when said locking pin is received in said pin-receiving slot said peak bracket or chord knee bracket and chord are locked in said open position in the absence of other forces on said sliding locking frame, and when said sliding locking frame is moved away from said axis of rotation to withdraw said locking pin from said pin-receiving slot, said head of said lock-out bar moves into said opening arranged to reversibly receive a portion of said lockout bar to thereby prevent said sliding locking frame from moving back towards said axis of rotation to again lock said peak bracket or chord knee bracket and chord in said open position, and when said portion of said lock-out bar is received in said slot (50, 52) to reversibly receive a portion of said lockout bar said peak bracket or chord knee bracket and chord can be rotated to said second closed folded position; and whereby when said peak bracket or chord knee bracket and chord are rotated back to said open position said locking pin is moved back into said pin-receiving slot by said first spring to thereby again lock said peak bracket or chord knee bracket and chord in said open position.