Navigator #14, May 2005
Part Design Matters
When injecting plastic, there are many
variables that can take place to make the
intended part not to print. There is shrink,
mold temperature, drying of the material,
cycle time, and the packing of the part.
Most of these issues can be corrected at
the press with processing. This allows the
press operator to experiment with different
settings and variables to "tune in" the right
settings to make the part run as expected.
One variable that can rarely be corrected at
the press is a flawed part design. If the
part is designed with inconsistent wall
thickness, lack of ribbing for structural
support, and lack of coring to thick areas,
the parts will shrink, distort, and warp out
of tolerance.
Another variable that can effect the part is
the material. Some materials lend
themselves better to flatness than others.
Other materials flow better in the mold,
while others cool faster. This is why
prototype tooling has been value added to
companies. The customers can pre-qualify
their design and material in a prototype
tool before investing top dollar in
production tooling.
Typically, production tooling is a multi-cavity
tool made from hardened tool steel with
automatic slides. The cost and lead-time to
modify these tools can cripple a budget
and the product release date. Rapid
Tooling is made in 2-4 weeks from
aluminum with manual slides and hand
pick-outs. In rapid tooling, changes can be
made with minimal costs in a few days so
you can qualify your part design, which can
be the difference of beating your
competition to market!
Due to thick plastic sections, this part had sink and warp issues. By coring the thick sections,
this allowed the material to cool consistently to achieve an accurate and toleranced part.
By adding a rib for structural support, the second design
eliminated the warping that occured in the first design.
SLA Cosmetic Options
People have been priming and painting
SLA's for years to get visible samples for a
tradeshow, for marketing, or for a photo
shoot. Sometimes customers need
coloring of their SLA's to demonstrate the
use of individual parts in an assembly to
better explain their prototypes. Painting
can take a couple of days to complete and
can be costly on a budget. Glazing or
tinting can be a viable option for you. This
can be completed in the same lead-time as
your SLA.s for a minimal cost. The colors
are more transparent, unlike paint, but do
show variety to the prototypes.
Another option to an SLA finish is vacuum
metalizing. This allows us to plate the SLA
with high polish metal finishes. A variety of
colors can be done from silver chrome to
gold chrome. This process takes 4-5 days to
complete. The cost is quoted on a job to
job basis, but on average the cost is around
$500-$700 a lot charge.
From vacuum metalizing to tinting, Vista can add color to your next SLA project.
Vista has Moved and Expanded
Vista has combined their rapid prototyping
division and their rapid tooling division
under one new roof. The facility has 50%
more room from the previous two plants
with another 6000 more square feet for
expansion in March 2005.
This has been an exciting event. With the
new space, Vista brought in another high-
speed mill with a live 4th axis. This has
increased Vista.s rapid tooling capacities to
handle most any tooling package.
With all the employees under one roof,
cross training, and standard shifts allow the
company to utilize their original rapid
prototyping facility hours in being opened
two shifts, seven days a week.
Please set up a time for your personal tour
of the new facility. This will allow you to
see some of Vista's best samples and a few
of our many success stories!
Both the Rapid Prototyping and Rapid Tooling Divisions reside under
one roof in Vista's new and larger facility in Vadnais Heights, Minnesota.
T E C H N O L O G I E S L L C
Tel (651) 653-0400
Fax (651) 653-0900
www.vistatek.com
E-mail:
prototype@vistatek.com
