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Scientific molding, explained for buyers
Most molding problems a buyer sees, like short shots, flash, warp and dimensions that wander from lot to lot, come from a process that was set by feel. Scientific molding sets it by measurement.
Machine settings are not the process
Two presses set to the same numbers will not make the same part. Material viscosity changes lot to lot, check rings wear, and water temperature drifts. A process tied only to machine settings moves with all of it. A scientific process is built around what the plastic experiences in the cavity: pressure, temperature and time. We then hold the machine to whatever it takes to repeat that.
How we do it
Develop the process from data
We run viscosity, cavity balance, gate-freeze and pressure-drop studies to find where the process is stable, not just where it happens to make a good part today.
Separate fill, pack and hold
DECOUPLED MOLDING® methods let us control each stage of the cycle on its own, so a change in one does not quietly move the others.
Watch every shot
Two RJG eDART® systems read in-mold sensors on every cycle. When a shot falls outside the window, the part is flagged and contained at the press.
Write it down
The finished process is recorded in machine-independent terms. It does not live in one technician's head, and it can be moved to another press.
What you get as a buyer
- Parts that repeat. Lot to lot, shift to shift, and after the mold has been pulled and rehung.
- Fewer surprises at incoming inspection. Suspect parts are caught at the press.
- A process you can move. If you scale, or move tooling later, a documented process transfers.
- Faster root cause. When something changes, there is data to show what changed.
Who runs it here. Our process development is led by an RJG-certified Master Molder® I and II who spent years as an RJG Train-the-Trainer, teaching these methods to other molders, before running his own floor. About us.
Common questions
What is scientific molding?
Scientific molding is a way of developing and running an injection molding process based on data about what the plastic experiences in the mold, such as cavity pressure, rather than on machine settings and operator experience alone.
What is an eDART system?
eDART® is RJG's process monitoring and control system. It reads sensors in and around the mold on every shot and can flag or divert parts that fall outside the process window.
What is decoupled molding?
DECOUPLED MOLDING® is RJG's method of separating the fill, pack and hold stages of the injection cycle so each can be controlled on its own. It makes the process more stable and easier to transfer between presses.
What does an RJG Master Molder certification mean?
Master Molder® is RJG's advanced certification in scientific process development. Master Molder® II requires Master Molder® I first. Our process development is led by someone who holds both and who trained other molders as an RJG Train-the-Trainer.
Next step
Send us a print
A drawing or STEP file is ideal. A photo and a description is enough to start. You talk to the person who will run the process.