7.0 KiB
Injection Machine Automatic Connection Upgrade
How-To Guide for Upgrading Your Injection Machine and Molds
Improve the speed, safety, and efficiency of your injection process by upgrading your machine and molds. For any injection mold with a threaded connection to the machine nozzle, simply install a brass garden hose connector.
User Location: Ajaccio, France
Steps
Step 1: The problems with injection
The injection machine effectively highlights plastic issues and illustrates the recycling process. However, for high-volume production, it can be slow and challenging.
Here are the primary issues:
- Molds are difficult to attach; they often clog with molten plastic, complicating assembly and necessitating cleaning after each cycle.
- Unmolding is time-consuming; threaded mold connectors create undercuts, complicating unmolding.
The upgrade system must accomplish the following:
- Enable single-movement mold attachment and detachment
- Improve operator comfort
- Minimize production waste
- Allow use with gloves
- Reduce cycle time
- Eliminate the need for cleaning between cycles
Using a brass garden hose connector, found at garden and home improvement stores, can facilitate efficient mold connection.
Step 2: Bill of materials:
You'll need:
- 1 x 1-inch female brass garden hose connector with external threads
- 2 x 1/2-inch male brass garden hose connector with internal threads (or another size to fit your mold)
- 1 x 1/2-inch brass endcap
These items are available at most hardware or gardening stores.
- 14mm (9/16-inch) long piece of M14 threaded rod or 14mm (9/16-inch) diameter round stock (M14 threaded rod is recommended for its suitable diameter, though any 14mm round stock will suffice)
- 10mm (3/8-inch) drill bit
- A drill and a vise
Note: Ensure compatibility with your machine and mold; verify dimensions.
Metric to inch equivalents: 1/2 inch = 15x21 threads
Step 3: Spacer fabrication
Begin by fabricating a spacer: a cylinder with a 14 mm (0.55 inches) diameter and a 10 mm (0.39 inches) central hole. Refer to the plans below.
An M14 threaded rod or screw is suitable and commonly available, but a 14 mm (0.55 inches) round stock is also acceptable.
Using a drill and vise, create the 10 mm (0.39 inches) hole through the spacer.
Ensure the spacer fits well in both the male connector and the 1/4 inch (6.35 mm) adaptor to prevent leakage.
Step 4: Assembly steps
Modify Your Mold
- Insert the spacer into the mold's 1/2 inch (12.7 mm) connector, ensuring it fits snugly and occupies most of the empty space.
- Attach the male brass connector on top.
- Drill through all parts with a 10 mm (0.39 inch) drill bit to enlarge the hole to 10 mm (0.39 inch). Ensure precise drilling to avoid damaging the threads.
Repeat these steps for each mold to fit them all with male connectors for convenience.
Assemble Your Plug
- Attach the second male connector to the end cap to create your new plug.
Modify Your Injection Machine
- Remove the current threaded nozzle and replace it with the brass female connector.
Step 5: Instructions for operation
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Prepare your mold and heat the machine.
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To inject, lift the female connector's exterior ring to remove the plug.
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Push the mold into the connector, which will latch with a "click."
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Inject into the mold.
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To remove, lift the connector ring and extract the mold, then replace the plug.
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Repeat as necessary.
This method achieved approximately 15 injections per hour, surpassing previous results.
Step 6: No more undercut shapes!
The rod fills the void inside the male connector, allowing molten plastic to flow through the 10 mm (0.39 inches) channel. This enables easy removal of the sprue from the mold (see Picture 1).
Attention: Remember the spacer to ensure smooth unmolding (see Picture 2).
Resources
Hardware
- 1-inch female brass garden hose connector (external threads)
- 2x 1/2-inch male brass garden hose connectors (internal threads)
- 1/2-inch brass endcap
- M14 threaded rod (14mm length) or 14mm round stock
- 10mm drill bit
Tools
- Drill
- Vise
Software
- No software required
References
Articles
- Make Your Own Injection Molding Machine
- Mold and Connector for Injection Molding
- DIY Injection Molding: How to Mold Plastic Parts In-House
- Injection Mold Construction (Wikipedia)
Opensource Designs
- Injection Machine Automatic Connection Upgrade ([filtered])