Additional information.

Currently, LED/PD legs are connected to leadwire with copper tubes as shown in fig1.
However, LED/PD legs are not cut before connecting to the copper pipes, so the legs are too long and easy to bent when applying force: this results the touch between heatlinks and LED.
Though wire is well clamped on the MNR and I hard to imagin the lead wires obtained strong force, it is better to cut the LED/PD legs properly to avoid bending of them but it takes a time...