Aluminum Prototypes: To hand-load or not to hand-load…that is the question!

In establishing the best course of action for your company’s prototype tooling needs, there are several factors that need to be addressed in the prototype tool design; cost should not be the only driver in that decision making process.  The critical factors that need to be assessed can have lasting effects on production tooling, and ultimately your production parts.  The volume of production parts, the complexity and tolerances of the production parts, and the structural integrity of the production parts are all influences that should be considered in prototype tooling design and part manufacturing.

When discussing and quoting prototype tooling for our customers, we like to assess what they are attempting to gain and learn from these production parts in order to offer the best suited applications for their desires.  For high volume production volume parts, we suggest that the production tool concept and design standards are mimicked as closely as possible, in order to facilitate any necessary learning curves from the prototype tool, and to validate a production tooling concept in moving forward.  On these tools, we design fully mechanical slide actions and any other necessary actions to achieve the part geometry.  These high-volume intent replicas can provide insight into potential issues through more rapid wear noted on the aluminum, in lieu of an expensive production tooling fix discovered down the line.  The insights gained from the production intent tooling reduces production tool down time to fix a potential issue, as well as the more expensive machining processes necessary to correct and implement the needed change.  These tools may be more expensive and time consuming in the short-term, but can yield much greater benefits over the long term.  In addition to high volume production parts, parts that require substantial structural integrity can also benefit from full mechanical prototype tooling.  When dealing in parts that require significant structural integrity, it is critical to establish the flow of material through the tool and in forming the part.  In our typical mechanical prototype tool, we also try to match the gate location that is determined for the production part in an attempt to produce the same flow characteristics that the production tooling would display.  Often times, mold-flow analysis can lead to a preliminary understanding how the part fills and the material flows through the tool, but as we have learned at RMS through countless prototype projects: “the proof is in the pudding”.  Gas traps, knit / weld lines, and various other flow anomalies are best detected in a physical, molded part.  Typically, we also like to utilize fully-mechanical prototype tools when part geometries are complex and/or tight part tolerances are required of the production parts.  Mechanically induced parting lines and shut-offs are more easily achieved with mechanical actions as opposed to hand-loads.

On the other hand, the low volume production part requirement, and parts with more simplistic geometries, can make hand-loads a cost-effective means to prototype parts.  In lieu of additional aluminum in the base to accommodate slide travels and the engineering necessary to make a properly functioning slide, some geometries and part requirement volumes tend to favor this option, when an undercut is necessary for part form and function.  Due to the additional labor required to physically remove the hand-loads from the molded part, the piece price on parts formed in this manner is higher.  By its nature, hand-loaded tools have longer cycle times as well, contributing to a higher piece price.

When assessing the prototype tooling options available on your next project, feel free to give us a call and let’s determine the most effective means to develop your new product!

Get In Touch!

Address:Rapid Mold Solutions

4820 Pacific Avenue Erie, PA 16506



E-mail: [email protected]