This paper describes the investigation of sparse-build tooling by Fused Deposition Modeling
(FDM®) aimed at rapid tooling with reduction in the amount of material. Sparse-build test
coupons having ULTEM as the material and varying air gap (sparse spacing), wall thickness, and
cap thickness were fabricated using the sparse and sparse-double dense build styles of the
Stratasys Fortus machine. The strengths and moduli of these coupons were measured in
compression and flexure tests. The strength/mass ratio and modulus/mass ratio were compared
among the various coupons, as well as with solid coupons, to investigate the effects of the two
build styles and the three sparse-build parameters. In addition, the effects of build direction and
raster orientation were also studied.Mechanical Engineerin
