Crawlspace insulation blocks: https://www.homedepot.com/p/Gibraltar-Building-Products-6-1-2-in-x-7-3-4-in-Foam-Vent-Plug-2-Pack-DVBP/202217267 $1.17/each
a) “perfect fit” rather than either having a gap or needing to break/squash them due to “standards, aren’t”
b) The store bought can technically be re-used, but not really in practice, and same for these ones.
c) Not as thick, but it’s more about keeping the air from moving than keeping the cold out.
d) The finger-hole is probably not much more net free area than having a gap, and having some air moving in the crawl space isn’t a bad thing.
100mm/s at 85% with air on 100W tube. I could have probably gone faster or less power, but that worked out well for scrap and I didn’t fine-tune further.
Also, just renewed licence. “Dang, already a year?” It was a no-brainer decision to renew when the popup hit. Thanks, Oz, Rick, and Lightburn team!
EDIT: I just realized that “You CAN have all three applies to LB, as well.”