Elevator Tip Balance weight rib crack.

[chickadee170mech]

Anyone seen or done a repair for the elevator balance rib. Have a B with a crack from the aft screw that goes about 1/2 an inch aft of the screw head behind the weight.

[GAHorn]

Are you speaking of the PK-screw which attaches the weight itself?

<edit> Many of the lead wts are attached via PK screws instead of the CR-rivets called-for in the IPC.

[n2582d]

Chickadee,
If you were a member you would have access to an excellent explanation with photos of how Metal Master and Doug repaired their A model elevator tips. Cessna's Structural Repair Manual has this page for repairing control surface ribs. Be a lot easier to replace the entire rib.

Control Surface Rib Repair.png

[chickadee170mech]

Are you speaking of the PK-screw which attaches the weight itself?

<edit> Many of the lead wts are attached via PK screws instead of the CR-rivets called-for in the IPC.

Yes, from the aft screw hole we had a crack going aft in the rib. We elected to replace the whole tip assembly from an L-19 so that we also removed some ugly tip dents.

[GAHorn]

Are you speaking of the PK-screw which attaches the weight itself?

<edit> Many of the lead wts are attached via PK screws instead of the CR-rivets called-for in the IPC.

Yes, from the aft screw hole we had a crack going aft in the rib. We elected to replace the whole tip assembly from an L-19 so that we also removed some ugly tip dents.

That’s a good plan. Only one caution: Be sure to check the control-balance after substituting an L19 tip (w/weight) for the 170B tip (w/weight. When tip-assy’s are exchanged the weights are usually heavier than req’d so material can be removed to balance the control surface.)

(hint: easy way to lighten an L19 wt is with a drill bit)