As my 2nd Edition SM Force continues its journey ( ;) ), a reused piece provided the opportunity to fill a few base gaps (1-3 mm); here is the process and the results (clicky for biggy) ...
(1) 'Paint' the putty (directly from the pot) into the gaps, just above the level of the surface, wait 24 h ...
(2) Following shrinkage, repeat (1), wait ca. 48 hours, to be sure that the putty had fully-hardened,
(3) Sand with a rough, 'nail', sand-board (to remove the bulk) and then finish with 1200 grit, dry and damp, paper ...
Notwithstanding the time it took for setting (not that it was all required), I was quite pleased with the gross filling of the gaps and ease of sanding. However, closer inspection reveals surface 'pitting'/'sinking', in comparison to the surrounding substrate; whether this was due to bubbles, during shrinking/hardening, or 'pulling' during sanding, is unknown.
Conclusion: Good for bulk, 'table-top', filling, but needs extra finishing for 'quality' surfaces. Of course, multiple, diluted, applications are certainly going to help, but, time is then an issue.
