|SolidWorks Featured Author Blog - June 2012|
Got Technical Content?
In case you haven’t noticed, SolidWorks has recently started adding a lot of technical content to the SolidWorks Forum. Numerous part files are available to download that contain a wealth of information including well thought-out design-intent and fully commented features. All of these parts can be thoroughly examined using the 2012 SolidWorks Part Reviewer Add-In. The intent of this effort is to show tips, tricks, and unique modeling methods for a variety of part categories and features including machined components, sheet metal, weldments, and surfacing.
Here is an outline of one of the many interesting examples; a simple tricycle. But just like everything in design and modeling, nothing is really simple.
This assembly contains 20 unique components with 26 components total. The wheels and the handlebars are under constrained turn freely. There are four mirrored components.
The assembly starts with the top frame part which has a layout sketch controlling the height, length and seat post angle. The use of sketch pictures could also have been used to help create some of layout sketches.
The seat and handlebars were then built and added to the assembly. The front fork and large wheel were then added to the assembly. The grips, fender and pedals were added to finish up the front of the assembly. Most of the remaining parts were then added working from the top down to the rear of the tricycle.
The small wheel was created as a copy of the large wheel but also could have been designed as a configuration of the large wheel.
For simplicity, the tricycle has some examples of multi-body parts that could have been created as sub-assemblies. The use of external references was minimized to only two features. One of those features was an assembly level cut propagated down to the top frame part. The other feature with an external reference was a cut on the forks (axle hold cutout) which used convert entities to trace over existing geometry from the fork axle hold.
Interference detection is used to ensure the parts fit together correctly. There are a few examples of equations driving geometry and pattern instance counts. There is one assembly cut named Top Step Cutout that cuts through the Top Frame that is propagated down to the part.
Most of the models were created using standard solid modeling techniques. The seat is made using surface bodies and then turned into solid model. Some of the other parts in the assembly do show the use of the offset surface command, where the copied surfaces are used to cut solid geometry. Some components do have multiple bodies including the Bell and the two different wheels.
All the parts have comments in every feature. All sketches are fully defined.
The Top Frame part is an example of multi-body solid with two revolves, one sweep, two surface cuts and uses the combine command. It also has an assembly level cut that was propagated down from the assembly.
The Seat with Post model is the one part in the tricycle assembly exclusively made with surface bodies except for the post extrusion. It has two boundary surfaces (using one curve in each direction), two mutual trims, a surface fillet and uses the thicken command to create the solid.
Both Wheels have examples of circular patterns and equations driving the number of spokes. The number of spokes can be safely varied from 2 to 19 with all the corresponding holes and cuts correctly updating. Both wheels also have two examples of derived sketches, one for the spoke sweep path and the other for revolve at the end of the spokes.
The Handlebar model has a sweep that uses a Composite Curve to create the sweep path. The 3D sweep path consists of two straight line sketches added to the ends of a projected curve (using the sketch on sketch option).
The grip has three revolved cuts with two linear patterns.
The fender has a split feature and uses the move/copy body command to stretch it out slightly. It also has two different methods of showing how to trim the fender corners off.
The bell is multi-body part that has three configuration using move/copy body command to show three different positions of the lever.
The fork uses a two point spline to create a cut to set the caster and it has an example of multiple face full round fillet.
The simple cap part has an example of a vary sketch linear pattern used to cut pattern on the top of the part.
The Bell has three configurations showing the lever movement. The cap is the other part in the assembly that has multiple configurations.
For Users, by Users
SolidWorks has provided a lot of information created just for you, modeled by fellow users that have experience in creating real world parts. The examples demonstrate multiple methods to solve the same problem, and the comments impart vast knowledge explaining the “when” and “why” of feature usage as well as the “how”. You should find the models interesting and unique, so feel free to download as many as you want, and be sure and leave lots of comments.
Phil Sluder, mechanical engineer, owner of TriAxial Design and Analysis (http://www.triaxialdesign.com/), Certified SolidWorks Instructor, Certified SolidWorks Professional, a longtime member of the SWUGN committee, and leader of the San Diego SolidWorks User Group. He can be reached at firstname.lastname@example.org