Multi-ring spacer for gas turbine engine rotor stack assembly

A method for assembling a gas turbine engine including:

• defining a gap at an interface between a first and second co-rotating component;
• measuring an average axial length of the gap and measuring a kink angle of the gap;
• selecting a multi-ring spacer having a first ring and a second ring, the first ring having a first clocking position, the second having a second clocking position and being coaxial with the first ring, wherein a total kink angle of the multi-ring spacer is dependent on an angular deviation of the clocking position of the second ring's relative to the clocking position of the first ring;
• and
• matching a kink angle of the multi-ring spacer with the kink of the gap such that the kink angle of the gap is offset by rotating the second ring relative to the first ring.

A multi-ring spacer comprising:

• a first ring defining an axis and including a first axially facing out of square surface having a first kink angle;
• a second ring, coaxial with the first ring, and including a second axially facing out of square surface having a second kink angle;
• and
• each of said first ring and said second ring including a clocked position corresponding to an axially thinnest radial position, and wherein a total kink angle of the multi-ring spacer is maximized when the clocking positions have 0 angular offset.