Fujifilm Prescale - Mold Adjustment

PRESCALE
MEASURED OBJECTS
USES
BENEFITS
INDUSTRY
Molding, mold making, injection molding machine manufacture
APPLICATIONS
Checking for PL (Parting Line) surface contact, checking for distortion of molds and molding machines
CHALLANGES
1)
Since molds are composed of multiple parts, dimensional errors of each part tend to accumulate in the thickness direction. This means that the precision of the height of each part of the PL surface can deviate significantly from its intended value, resulting in excessive contact pressure, the failure of parts to make necessary contact, or the generation of burrs.
2)
When force is applied to clamp a mold, the platen tends to bend, which in turn causes the mold to bend. As a result, the thickness precision of the molded product deteriorates, leading to uneven wear and shortened mold life.
MEASUREMENT
Product used: Prescale (LW, MS, HS)
1)
When a new mold has been fabricated, or during production, insert the Prescale between the PL surfaces and measure the pressure distribution. (Application Example 1)
2)
To check the impact of platen bending, insert Prescale between the platen and the mold and measure the pressure distribution. (Application Example 2)
Application Example 1
Checking mold PL surface contact
Insert the Prescale between PL surfaces and clamp the mold.
The prescale must be cut to fit the shape of the PL surfaces. The pressure can be visualized in accordance with the density distribution of the color-developed Prescale. The following checks can be made:
  • Check the PL surface are even
  • Check that contact is not one-sided
  • Find the points where contact is stronger than intended
  • Check that there is no risk of burr formation, due to failure of contact where contract is necessary
Application Example 2
Checking contact between mold and fixed side platen (movable side platen)
Insert Prescale between the mold and fixed side platen (movable side platen) and clamp the mold. The Prescale must be cut to fit the shape of the locating ring and screw holes. The pressure can be visualized by the density distribution of the color-developed Prescale, thereby making it possible to assess the degree of distortion of the molding machine when the mold is clamped.
RESULTS
Application Example 1
Checking mold PL surface contact
[Not good]
[Good]
Application Example 2
Checking contact between mold and fixed side platen (movable side platen)
[Not good]
[Good]
BENEFITS OF PRESCALE
1
When fabricating new molds, it is possible to produce ideal molds with even contact over PL surfaces.
2
Thickness precision and prevention of burring is improved, resulting in finished products of higher quality.
3
Effective mold life is lengthened.
4
The degree of platen bending and contact with mold can be easily checked.


Without using Prescale
Since PL surface contact cannot be checked or adjusted, burring of finished products occurs easily, and thickness precision is limited. In addition, mold life tends to be relatively short.
Using Prescale
The ability to check contact using Prescale and thereby adjust PL surfaces makes it possible to determine the causes of defects in finished products, thereby improving plant utilization and to increase mold life. Prescale also makes it easy to check the degree of platen bending and contact with the mold.