Maybe my problem with the Q20 was another one as discribed above with the Q30. There Deutch and English are not my native languages. (I'm dutch), I did not translate/ understand the problem in the right way I assume. Greetings Marc.

I used the Quest in the rain. So the upper and lower shaft where wet. and soms minor sand/ dirt was left on the lower plastic shaft. On the field I could slide without any problem the lower shaft in the aluminium upper shaft. But at home, I was unable to get the lower shaft out. I tried everything WD 40, silicone spray. I disassembled the coil and put the lower and upper shaft in a bucket filled with hot water. The upper aluminium shaft was a little wider I assumed, this through the temperature of the water. At one moment my wife holded the upper shaft, and I pulled firmly the lower shaft, at 5 minites trying, the lower shaft came loose from the upper shaft. When I investigated the lower shaft, it seemed that soms minor sand particles where pressed in the lower plastic shaft. Because there is only some 1/100 mm space between the upper and lower shaft (to prevent wobbling), 1 or 2 hard sand particles are enough to block the sliding. After the lower shaft was loose, I used some wd 40 and/or silicone spray cleaner in the upper shaft. After this issue, I never put the dirty lower shaft in the upper shaft in the field, but at home when I cleaned it. But be carefull, I was afraid that I demolisched my detector. So do try this method at you're own risk. With the coil disassembled. Greetings Marc.

I had the same problem with the Quest Q20. It was caused by a tiny sand piece. I used WD 40 and silicone spray. Finally the lower shaft came loose. Greetings