Adapter for spline installation jig

A system for assembling a frame product that includes a frame member comprising:

• a jig having a center platen surrounding on each side by an adjustable fence, each fence movable between a lowered position and a raised position;
• and
• an adapter that is detachably coupled to the center platen of the jig at selected location thereon, the adapter comprising a body having an inner face and an opposite outer face, the body including a first leg and a second leg formed at a right angle to the first leg, the first and second legs meeting in a corner of the body, the first leg including an elevated first end block and the second leg including an elevated second end block, the first end block including a first inner contact surface and the second end block including a second inner contact surface, the inner face of the body including a recessed inner ledge that is disposed at least partially in front of the first and second inner contact surfaces, the corner of the body including a guide pin holder that is configured to receive a guide pin for locating and holding a flexible substrate that is for placement across the frame member and for capture between the plurality of splines and the frame member.