Acryl thread and screw locking solutions

[Murdock]

I have a little problem with my M49 build.
I've build it like the original with three acryl pillars with threads inside. These get screwed to the PCB with a screw from the bottom of the PCB. And then I screw brass pillars on top as the capsule connections.
The question is, how can I "lock" the screw which fixes the acryl pillar to the PCB? Neumann seems to have used some kind of glue.
It is a 4mm acryl pillar where I drilled an M2 thread. So there is not much material left...
I tried to use acryl glue but the pillar cracked. I think because the glue somehow expands while drying...
Do you know of any solution which does not expand and locks the metal screw? Sounds counterproductive as that's probably how screw locking solutions work, right? By expanding and filling the gaps between screw and thread.

 

[Majestic12]

A small drop of superglue should work fine. Or use low strength loctite (blue or red).

Or just put it on the screw head and not the thread itself.

 

[Bo Deadly]

Sounds like a job for loctite. But red is potentially very difficult to undo depending on the amount of threads involved. I would use blue until you decide you really need red.

 

[Murdock]

Thanks for your suggestions!
In the meantime I found a plastic glue from UHU on Cyanacrylat basis which seems to be fine.

I also thought about loctite but I read that it expands. That's how it works, right? It get's in to the little airgaps between screw and thread and expands.
Or did you have good experience with loctite and acryl?

 

[sahib]

You can also use nail varnish.

Acrylic based glue cracked it not because of expansion, but because on contraction. The pillar did not have sufficient wall thickness to cope with the stress.