I worked on the honeycomb pin today, and am thinking about redoing the settings.
The problems with the loose fit- besides the hassle of filling the gaps with solder- are that the solder flowed up between the two pieces of tubing, messing up my nice crisp shelf that the stone was to sit on and requiring cleaning up; and that the whole process pulled the centers of the sides in a little bit- not much, but enough to make an 8.1-8.2mm stone not quite fit.
I spend some time today cleaning one of these up, and it's now close to a fit... but it's still not ideal, and I'm thinking that I may want to make 2 more settings, and this time cut superthin sheet into shims that will fit between the 2 tubes on each side. This will help the positioning, and reduce the amount of solder needed, which are both of the good.
I will probably try that tomorrow.