In 1941, Earl Blackburn, vice president of J.M. Huber Corporation's Oil and Gas Division, solved a long-standing problem in Panhandle oil field production by inventing the Huber steel-bladed paraffin scraper. Before it became a standard part of oil pumping equipment, paraffin wax dissolved in crude oil would precipitate and congeal on the inside of a well's tubing, sometimes stopping the flow of oil completely. Removing the buildup required pulling thousands of feet of rods and tubing from the well and cleaning them with steam, caustic, or chemicals before reinstalling them. Blackburn's original prototype was three feet long, welded to the rods, and used with a rod rotator he also invented; as the rod string moved up and down and rotated, the scrapers shaved accumulated paraffin from the tubing so the wax shavings could be carried to the surface by the oil flow. A 1941 test on a Huber well ran for two years without paraffin trouble, and avoiding repeated cleaning greatly increased production. Although other companies quickly sought the invention, it was not offered for sale until 1946 after World War II, when the design was revised to scrapers three to four inches long installed at intervals along each rod. The scraper remained a key component of successful oil production in the Panhandle field and continued to be sold. In pumpjack operation, a large electric motor drives belts, a gearbox, cranks, Pitman arms, and a walking beam that raises and lowers the pump and sucker rods in the well; as the rods rotate one-quarter turn on each stroke, the Huber scrapers remove paraffin from the tubing, and the shavings rise with the oil to the surface for storage and treatment.