On Sun, 20 Jan 2019 13:43:34 +0000, newshound
wrote:

A merit of this is that it can be
solvent welded either to a "footer" strip maybe 8 mm wide, which will
provide stiffening and avoid the ping problem

....and the problem where the spacer rides up, 40 thousand washers slip under it
and mix with the washers on the other side, and prevent the spacer from settling
back down until ALL the bits are removed, the spacer is reseated, and the bits
sorted and replaced....


Aaaargh.