How to Increase Sensitivity of Inductive Proximity Sensors

Some time ago my LJ18A3-8-Z/BX 8mm inductive sensor decided to decrease its sensitivity to 4 mm, don't ask me why, and I hadn't a new one to replace, so ,during various tries to revive it, I discovered something very interesting.

Step 1: Yes, We Can...

Placing a little magnet near its sensing head increase its sensitivity by several mms. You have to try different types of Neodimium magnets and discover experimentally which side makes the trick (the wrong side don't) and finally glue it in the correct place with cyan glue.

Step 2:

I then tried with the sensor of my 2nd printer, a different probe 8mm. I was in trouble because of the glass I use (5mm oven inside glass) and the aluminium bed, poorly magnetic, but the trick of magnet was effective this time too.

As you can see in the picture I tried with 2 magnets to increase more the sensitivity and it increases, but once fired and rised from bed 10-20mm the sensor remains in that state for a random time (5min or more) before switching down, so I still have to investigate deeply...

Step 3:

I hope this trick will help someone...