Lightweight construction is necessary to reduce mass, yet rigidity is also essential. Tubular aluminium, magnesium, and wood have been used, and the shells skeletonised. Low friction pivots require forces of no more than 2-50 mg maximum applied at the stylus, to move the arm horizontally or vertically. Unipivots are often used to achieve this.
"Thanks for the amazing job you did on the collection of OLD 45's that I sent! They were not in very good condition with the numerous scratches. I had been hanging on to them for 35 years, so, was I ever pleased to be able to listen to them again without the scratches. Another shipment will be coming your way!! Thanks,"