I am having an issue with my top bar shrinking. It is a 10 foot long 2x6. It has shrunk about 6 mm so far. It was green wood, not kiln dried (I can’t find KD 2x6s in my area) so this isn’t a complete surprise. Some of this movement may be a one time thing as the wood dries, but some of it is likely to be seasonal.
I would like to get a stable platform and avoid running the calibration process again, so I was thinking of moving to a unistrut top bar. Something like this Unistrut Design, but I don’t want to replace my entire frame.
If I use unistrut as my top bar, I still have to affix it to the wood that is moving. Does anyone know of any expansion mounting that exists for unistrut?