The Drammen River was one of the core areas for sawmills and lumber trade in Norway, and much of this activity was concentrated in Eiker. The merchants of Drammen dominated the lumber industry, and many of them also owned waterfalls, sawmills and farms in Eiker. Industrial activities of many kinds were also initiated here. Most of these proprietors - also called the "plank nobility" - did not live permanently in Eiker, but were nevertheless an important part of the local community.

Friedrichsminde

At Friedrichsminde, everything from nails, cutlery, irons to farm and forestry tools and work wagons, to name a few, was produced. The products were known for their good quality, and cutlery with wooden and bone handles in particular attracted attention.

In a review in Copenhagen in 1788 it was stated:

-'All kinds of ironmongery of fine English polish', now manufactured at Mr. Frantz Neuman's ironmongery factory at the farm Stensrud, which is the first of its kind in Norway. It is starting to get a good sale, preferably table knives with bone and wooden handles, as the work is good and the price cheap'.

An old drawing of the factory shows that there was a dam of carved stone boxes across the river with stone walls at Modumsida. A sawmill at Eikersida received water from a hatch in the dam, while two other hatches provided water to the mill and waterwheel that powered the grinding machine, the bellows for the ace, and the hammer in the hardware factory at Modumsida.