Log hive construction
The chestnut log is 27 inches long by 20-24 inches wide, being oval in cross section. The hole is 14-16 inches diameter.
The plunge cuts were started with a Makita electric chainsaw with a 16 inch bar, which is easier to control than the 70 cc Sachs-Dolmar 123 petrol saw used for the deeper cuts.
After the long square section pieces were removed, the electric saw was used to cut radially up to the circumference mark all round at about half inch spacing.
The residual wood was chipped out to the circumference mark with a 2-inch gouge and mallet.
Jan-Michael's film of John Haverson's and Matt Somerville's log hive construction: https://www.youtube.com/watch?v=pBikO86q130
Matt Somerville's blog page of his log hive: http://beekindhives.uk/2015/07/15/life-in-a-log-hive/
French website on log hives including film: www.ruchetronc.fr/ruche_tronc