Hi Keith, I have found that many breadboards are very porous, do not have the plastic all the way through. A lot like modern ice cream which is whipped and if you actually let it melt, half the volume vanishes.
One other thing I discovered is that the plastic melts at a reasonable temperature (150C?) and can be moulded. I am going to try and make a mould for my windlass brake, which needs replacing but was custom made. Stand by for further developments...
Don't believe everything that you think.