Born at Esrum, some 22 miles north of Copenhagen, on 28 May 1725, Krabbe was the son of a regimental quartermaster. His first marriage, to Cæcilie AndreaBille at the naval church at Holmen, established links with two important Danish naval families - the Billes and the Stibolts through his bride's parentage. He had three marriages altogether which all ended with his wives' deaths.
Career
He joined the navy in 1741 as a very junior cadet, and in 1746 saw service in Sydermanland which was with the squadron off Algiers. Promoted to junior Lieutenant in 1749, he was granted, in 1750, leave of six months to stay at Bornholm. In September of that year he started as an apprentice at the Construction Commission and embarked two years later together with Lieutenant F. C. Kaas on a study tour to Britain, France and Holland to learn their methods of shipbuilding. This tour took four years and included England, Brest, Rochefort, Toulon, Italy, Pisa, Venice, Naples, Marseilles and Amsterdam. He returned in November 1756 and was appointed a full member of the Construction Commission. In a very short time he became responsible, together with Lt. Kaas, for the building of a chebek to an Italian design, and the joint design of the frigate Christianborg. When Kaas was posted to the ship-of-the-line, Krabbe alone supervised the building of this frigate. Late in 1757, using the best of French frigates as his inspiration, Krabbe produced designs for a new frigate which resulted in two new ships being built - Søe Ridderen and Langeland. In September 1758 Krabbe was officially appointed as Fabrikmester, master shipbuilder to the Royal Danish Navy and his first ship-of-the-line was designed. In 1761 he was appointed as an advisor to the committee for the construction of Helsingør harbor. In 1768 he reported on the condition of the harbour at Christiansø, with recommendations for improvements. In July 1772 he retired as fabrikmester.
Krabbe's ships
In 1766 complaints about the cost of Krabbe-designed ships were made by Dannesjold-Samsøe of the Construction Committee. Although the ships were broader than earlier designs, their lower deck batteries were no more efficient, and more costly for a 50 gun ship than the proven 60-gun ships previously built. The following ships are attributed to Krabbe ;Ships-of-the-line
