Cutting Costs in Short Run Injection Molding
8 1/2 x 11 Paperback 110 pages
Price $28.00 Buy Me
This book is published by Morgan Industries, a manufacturer of tabletop injection molders. It deals with the subject of low cost tooling or molds for machines of this type. A perfect companion to our book # 010. A typical injection mold will last for a million parts and cost $20,000 to buy. What do you do if you only need 5, 50 or 500 parts? This book answers that question with rare information on simple hand operated molds, semi automatic molds and epoxy molds. Learn about gating, venting, draft, shrinkage and other mold design basics, along with practical advice and helpful tips on using common plastics.
Includes many case histories showing sample parts and the molds that made them, followed by an analysis of the design choices, cycle times and cost comparisons to other methods. You could probably buy a small machine with the savings from making just one mold.
Example of a Case History
| Original Method | |
| Purchase 75 gears - drill and tap hubs. | $450.00 |
| Short Run Molding Method | |
| Tool cost - 12 hours x $10 hr. +
materials olding cost - 4 hrs. x $5 hr. + materials |
$125.00 $25.00 |
| Total Savings | $300.00 |
In addition to all the great practical information in this book, you also get 34 actual case histories. These are real world examples of parts that were made with simple shop made tooling. They cover a broad spectrum and include molded in inserts, semi automatic molds and cast epoxy molds. The small gear on the left is a good example of a part made in an epoxy mold. It was injected from glass filled nylon at a rate of 20 parts per hour. The total cost for parts and labor to make the tooling and inject the parts was $150.00 for 75 pieces. The total cost to purchase the same gear and then drill and tap the hubs would have been $450.00. The total savings was $300.0 for one small batch of parts. You can see how easily you could justify the cost of a small machine.
Contents of Book
- Chapter 1 - Injection Molding Process
- Chapter 2 - Tool Design and Building
- Chapter 3 - Part design and Material Selection
- Chapter 4 - Epoxy Tooling
- Chapter 5 - Case Examples of Short Run Moldings
- Chapter 6 - Material Handling
- Chapter 7 - Injection Molding Equipment