When creating your design for rapid prototyping, there are many things to consider. It is important to understand the many aspects that go into 3Dprinting in order to select the right material and machine to construct your part. Here are is a list of the top 10 things to consider when prototyping:
Rapid prototyping (a.k.a. 3D printing) processes use .STL format files for build set up and part production. While native CAD can usually be converted to .STL format, when done outside of the native software, upon occasion, issues may arise, causing build failures or missing features. Sending your CAD in .STL format minimizes the chance for errors.
9) Multiple Shells or Unshared Edges
Good .STL files typically contain only 1 shell and should never have unshared edges. Multiple shells and unshared edges usually signal an uneven topography, meaning surfaces may be overlapping or disconnected from one another. If multiple shells and unshared edges are left in the file it may not build as intended, causing missing features or the part might build in separate pieces.
8) Verifying the Unit of Measurement
Be sure to indicate what unit of measurement your file was originally designed with. Harvest works in inches and can convert files from metric units. However noting what unit of measurement was originally used will save time and eliminate potential errors.
7) Designing for the Process
Every rapid prototyping process has its unique nuances and design limitations (tolerance, feature definition, material properties, etc.). These unique process/material characteristics should be considered when designing your prototype part so offsets, variances, and modifications can be implemented into the CAD model(s).
6) Choosing Price over Process
While pricing is always a consideration when prototyping, the primary concern should always maximizing functionality and achieving the desired objectives. Going with the lowest price point between processes may result in a prototype that does not function as desired or meet your needs.
Explaining your specific prototype needs for fit, form, finish, and functionality will help a Harvest project manager assist you in choosing the best option for producing your prototype. Whether its water resistance, surface smoothness, or painted show model aesthetics, the more detailed you can be the better we can optimize our processes/post-processes accordingly.
4) Small Features/Thin walls
Each process and material have a minimum feature size. This can vary from .010″-.030″. Understanding this limitation can help you select the best options or modify the CAD model(s) for your desired result.
3) Tolerance Variance
Rapid prototyping (3D Printing) processes are primarily free-form production systems and thus they have lesser tolerance control than traditional manufacturing methods like CNC machining and injection molding. These processes are still accurate within thousands of an inch, but certain designs (i.e. interference fits/line-to-line designs) need to account for slight dimensional variance.
2) Application Consideration
Your prototype’s application should be at the forefront of decision making when choosing a process or material. It is of great benefit for you to fully explain how your prototype will be used so a Harvest project manager can provide accurate assistance. While your design may be well suited to a particular production material or process, your prototype’s application may not be well matched to certain 3D printing processes and materials.
1) Rushing the Results
Whether you need your prototype in a couple of days or a couple of weeks, special care must be given not to rush the design/CAD modeling process and make unnecessary errors. Taking the time to review your final design for potential problems and reviewing these tips could ultimately save you from a costly mistake.
For more details and information on CAD designs and rapid prototyping, contact Harvest Technologies for a professional consultation.