Tinius Olsen was born in Kongsberg, Norway, in 1845, one of eight children. He graduated from the Horten Technical School in 1866 and became the foreman of the machine department at a large naval machine shop. Olsen was dissatisfied and after trying to find work in Newcastle, England, left for America. The 24-year-old Olsen arrived in Philadelphia in August 1869 and found employment with William Sellers and Co as a designer.

Olsen met the Riehlés brothers, proprietors of a small workshop. The Riehlés had received an urgent request for a machine to test the strength of boiler-plate. Weak plate materials caused frequent boiler explosions, especially on steam boats that were traveling up and down the Mississippi. The brothers asked him to produce engineering drawings for such an instrument and in his spare time Olsen designed and drew precise plans for the first boiler-plate tensile testing machine, with a capacity of 40,000lbf.