JEC COMPOSITES MAGAZINE - Issue #133 - March/April 2020 - 156

ADVERTORIAL
This large demonstration part
is one of twenty similar parts
which when combined become
a production mold for a large
yacht hull.

Things to Consider
With the addition of the MT, selecting the
best size and configuration for an LSAM may
not be quite as straightforward. It depends on
the material being printed and the size of the
parts needed. Of these two, the material being
printed is the most significant.
For purposes of machine selection,
Depending on
reinforced thermoplastic composite
materials for room temperature or
the item being
low temperature applications such
printed, it is
as foundry patterns, boat plugs, boat
possible to print and yacht molds, building structures
as much in a
and the like can generally be bonded
single shift as the securely with a variety of industrial
adhesives. For these type of parts,
large machine,
even for really large parts, the smaller,
printing a single less expensive machine may be a betpart, can do in 24 ter choice. The part can be separated
into sections which can be printed inhours.
dividually and bonded into the final,
potentially extremely large structure.
This approach can be faster than printing the
large structure as a single piece on a larger,
more expensive machine. To better understand this, we turn to the basics of the print process. Additive manufactured parts are printed
in layers. The speed at which a layer can be
printed depends primarily on how long it takes
for the polymer being printed to cool enough
to support the next layer. This layer cooling
time depends on the polymer and is not affec-

ted by the size of the part. Each layer of a particular polymer takes the same amount of time,
regardless of how big it is.
LSAM print heads can print faster, sometimes
significantly faster than needed for most parts.
Often it can print two three or more parts in the
cooling time required for each layer. The large
machine is only printing a single part, one layer
at a time, making it two or three time slower. To
print the part in one piece, the large machine
must operate continuously, around the clock,
sometimes for days. This is not a problem for
factories that operate on all three shifts but can
present staffing problems for single shift operations. With the MT, several different segments
of the same part can often be printed in a single
shift. Depending on the item being printed, it
is possible to print as much in a single shift as
the large machine, printing a single part, can do
in 24 hours.
For large parts made from bondable materials,
often the smaller, less expensive machine is a
better choice. Materials intended for high temperature applications, PSU, PESU, PEI, Ultem,
etc. generally are resistant enough to solvents
that they can't be effectively bonded. Few if
any, adhesives exist that can withstand the operating temperature or the thermal cycling these
materials experience. For these applications,
the machine needs to be large enough to print
the part in one piece, even though it could be
slower. The larger machines also offer the ability to print and trim at the same time, which
may be beneficial in some circumstances.
Since the print heads are the same on all Thermwood LSAMs, the smaller MT can be used
for these high temperature parts, provided
they fit in the available envelope.
Contact details : Thermwood Corporation
904 Buffaloville Road
Dale, IN 47523 - 812-937-4476
sales@thermwood.com - www.thermwood.com
The LSAM MT is the
ideal additive machine
for a variety of exciting
new applications

http://www.thermwood.com

JEC COMPOSITES MAGAZINE - Issue #133 - March/April 2020

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #133 - March/April 2020