I made a remix of this device (increased thickness, remade for acrylic panels, changed the size of the original) and I have it worked for more than six months.
Approaching the top thread, did not cause any problems.
Bottom thread supply, resulted in the destruction device.
Maybe it's my fault. I did a little filling.
However, I completely remade the original design.
I made a powerful console and changed profile
The thickness of my acrylic panels 7,6mm I made a device this size.
I added a model for 8mm thick acrylic panels.
Sorry for my English