Traditionally this cap molding was solid, but since a solid molding
this large is hard to come by, we substituted 2-1/4-in.
The foaming process on its own (disregarding compound formulation) enables a weight reduction in the part of at least 30% compared with conventional solid molding
Using a CAD file and CNC machine, the company implemented a process similar to machining a traditional pattern, building the shape directly into a block of solid molding
Pine trees and oyamel firs predominate if undisturbed, enmeshing their scraggly tops in one solid molding
Since Trial SO of the solid molding
is conducted with relatively high injection speed (40.1 mm/sec) and high packing pressure (62.1 MPa), the reduction of tensile strength at weld line, when compared to that away from the weld line, is almost negligible.
In most cases, a part designed for function ends up with less density reduction than the same part design for solid molding
and converted to foam, but with a much greater overall weight reduction.
A high-gloss surface equivalent to automotive Class-A solid molding
can now be achieved with the weight savings and other benefits of microcellular foam molding, thanks to a new licensing agreement between Trexel Inc., Waltham, Mass.
"With solid molding
, the part weight was 673 g, cycle time averaged 92 sec, and the finished part was unusable because you could not eliminate the sink marks or warpage," says Milacron product manager Jim Esser.
One of the most widely publicized, but perhaps least understood low-pressure injection molding technologies is the Thermoplastic Solid Molding
("TSM") process of Hettinga Technologies in Des Moines, Iowa.
Because of the fine, uniform foam structure, Cellmould parts with the same weight as solid moldings
have thicker walls and thus are more rigid.
The new group initially will consist of eight pieces for the bedroom, said Michele McPherson, national marketing director: Features will include hidden storage, a distressed scrubbed finish, raised panels and solid moldings
. It will retail for $2,999 for a seven-piece grouping.
The modulus of the composite material, and strength at 2% outer fiber strain, approached those of the solid moldings
as the glass content was increased (see Tables 2 through 4).