MEC 1011 - Design Communication I
Fall 2004 Final Project
Due at the final exam
This project will closely resemble the mid-term project,
but it will include more requirements for presenting your design and the
evaluation of tolerances will consider fit. Think of it as the mid-term with assignment 10 and assignment 11
tacked on. You may submit any prior work from the course. For example, someone
who made good clean models for the mid-term might further refine the design,
buff over the presentation and pitch it again as a final project.
Produce a concept sketch (freehand pencil on
plain 8 ½ x 11) of modest refinements to the design of a simple machine.
Produce a complete set of working drawings
for the refined design using Autodesk Inventor. Set up and use an Inventor
project file in V: /MEC/1011/Fall_04/Final/TXA/aaammdd/ that saves your models
next to or below itself. Your models should include logical
sub-assemblies. Use A-size portrait or B-size landscape sheets.
Develop a design guide, using Word, to compile
the rules of the design, ranging from aesthetics (ex. brushed stainless parts
fastened with black socket-head cap screws) to manufacturing process plans and
capabilities (capabilities include minimum reasonable tolerances and
what geometric restrictions apply, like draft for casting). Your guide
should also specify minimum clearances between mating parts. Consider
table and outline structures for your design guide (see example). Save your design guide
(.doc or .htm) in your Final project V: drive folder.
Exchange feedback with a peer through a complete
set of marked-up paper plots. After making all necessary changes based on
feedback, you must indicate who checked the drawings using the 'Checked by' iproperty.
Turn in a paper package consisting of:
A flat 3–hole cover (not 3-ring) with your
name on it
A title page including a rendering of your
machine in its environment
Your design guide and your concept sketch(s)
Your set of working drawings (printed 1:1 with
drawing scale of your choice. Fold B-size pages accordion style.
Your peer’s set of drawings marked-up by
you. Be sure to share the set with the author before turning it in.
You must turn in
this package to an instructor in person. Make sure the instructor records
the delivery by checking your name off a list.
Produce motion and assembly animation files (5M
max each). Animate sub-assemblies separately.
Produce a PowerPoint slide appropriate for the
36” plotter (17” x 17” sheet of paper). Your slide should
feature a rendering of your machine (500 x 500 pixels) surrounded by images of
your working drawings, similar to those hanging in the hall outside the
mechanical department offices (but smaller).
Update your electronic notebook to cover the
entire semester including the final project.
project must include at least 6 custom parts,
one sub-assembly, some standard fasteners or components, some mechanical
You may use your mid-term project as a basis for
your final project if it meets the above requirement or if you embellish the
scope to meet the above requirement. For example, if you designed a two-part
tap wrench for the mid-term, you could add in the taps, threading dies, and die
handle to go with the tap wrench. Or perhaps you could
design a case for the tap wrench.
You can start over and develop a new design if
it meets the above requirement. You may start with any existing design whose
drawings don’t yet exist. Draw from your imagination, experience or the
list of examples (see links to
- Completeness: Sketches, each working drawing, and
the set of drawings must be complete.
Sketches: Draw freehand with pencil on
plain 8 ½ x 11 paper. Include title at the top, notes that explain your ideas
and refinements, name of designer (you), your signature, and the date.
All Working Drawings: Include formal (consider
standard ANSI) title block and border. Title blocks include scale, author,
checker and date, title.
Assembly Drawing(s): Include exploded and
assembled views (at least one of each - your choice of ortho, section or
iso and consider two sheets) necessary to clearly show (consider detail views)
what parts and how they go together. Also, include balloons (on assembled and
exploded views), a parts list and good trails on any explosion. The
parts list should at least include Item number, Quantity, and a column to name
custom parts and clearly specify standard ones. The names of custom parts must
match titles given on part drawings.
Part Drawings: Include all views and dimensions
necessary to define the part geometry. Tolerance all dimensions to conform to
design guide with respect to minimum reasonable tolerances of relevant
processes and minimum clearances vs. mating parts. Note material, and units
(perhaps in title block).
Drawing Set: Include an assembly drawing for
each assembly and sub-assembly and part drawings for each custom part.
Challenge: Model and dimension in metric units.
Avoid Contradictions: Never use the
decimal places of the style (appearance) of a
dimension (unfortunately Inventor calls this the ‘precision’ of the
number) to round off a quantity. For example, if the length of a feature
is 1.625, you should not allow its dimension to state 1.6.
Dimension hole sizes
and list characteristics using hole notes (use numerator -like 2X- available
under dimension style). This requires the also desirable use of hole features to model holes.
Dimension a hole’s
location by referencing a centermark or centerline.
Place extension lines with visible
Avoid multiple parts per drawing or multiple
drawings per Inventor drawing file (.idw). Also, avoid multiple parts per
Inventor part file (.ipt).
Give meaningful names to your Inventor files.
If you’re stuck designing in English
units, think in simple decimal sizes when you design (like 1.6), and use
fractional sizes for stock and standard components only. When you use
fractional sizes (like 1.625), dimension them with a fractional style (like 1 5/8).
Follow dimensioning rules of Figure 12.48 like
locating holes in view looking down hole.
Place dimensions off the views (Figure 12.43).
Avoid over dimensioning (saying the same thing
Apply geometric dimensions and tolerances where
appropriate to lower manufacturing cost.
Tolerance consistent with process capabilities
as stated in your design guide.
Delete unused Inventor sketches (it’s
easiest to kill them immediately).
Avoid unused projected geometry in sketches.
This is most easily done by confirming the status of Tools/Application
Options/Sketch/Automatically Project Face Boundaries.
All work planes and axes exist for a good
Holes are placed on a 'Point, Hole
Center' (avoid extruding cut
circles or placing hole features on sketched circles).
Holes are tapped by modifying a hole feature (not by adding a thread feature).
Holes are dimensioned with hole notes
Specify part finish (using notes or symbols).
Where a part is symmetrical, indicate symmetry
with a centerline and tolerance the symmetry with a note.
- Complexity. Notice this is the LAST PRIORITY. Look
up at Completeness. Before you make your design more complex, consider
having a friend with a sharp eye look over your drawings. Your most
insidious foe is the missing dimension.
Add complexity only after you have completeness.
Links to Projects: