Why does the R-angle often appear on the blister & the solution
Quote from emerson on 2022-04-30, 23:24:25People often ask me why the corners between the mold and the base plate never fully suction to the bottom and always have a rounded R angle.🤔
The truth is, vacuum forming is a complex process that requires precise coordination between temperature control and vacuum shaping. While the vacuum shaping process is easy to observe, the subtle changes in temperature are much harder to detect. As a result, it's common to mistakenly assume that insufficient suction from the pump is the cause of this issue.😕
To address this, we decided to record a real-time video of the molding process using a thermal imager, marking three temperature detection points to showcase the temperature changes. Pay close attention to Temperature1: when the mold is placed directly on the stainless steel base plate and the 0.5mm thick PET sheet is pressed down and adheres to the base plate, Temperature 1 drops from 125°C to 78°C (the hardening temperature) in less than a second.
In this scenario, the rapid cooling process outpaces even the most powerful vacuum pump. As a result, the R angle of the formed material becomes quite pronounced!
>>>0.5mm PET attached to stainless base
If we place a wooden board under the mold, the cooling process slows significantly. In this setup, Temperature 1 drops from 125°C to 78°C over an extended period of about 4 seconds, compared to less than 1 second with the stainless steel base plate. This extended cooling time gives the pump ample opportunity to shape the material more effectively, resulting in a much sharper corner with less pronounced R angles.👍
>>>0.5mm PET attached to wooden board
By understanding the process and optimizing temperature management, you can achieve much better results. For example:
- Using a less heat-absorbing board as the base.
- Pre-heating the mold to 50°C before starting.
- Using a hot air gun during the molding process (don’t forget to set the material thickness to 3.0mm on your FORMART to extend the pump's operating time).
These adjustments can significantly improve the outcome.
Of course, if you prefer to rely on a more powerful pump to address the issue, that’s also an option. However, it's similar to upgrading a Ferrari that already accelerates from 0 to 100 km/h in 3 seconds by adding an even bigger engine to push it to 2 seconds — the cost might be far greater than you expect!😆
by Emerson
People often ask me why the corners between the mold and the base plate never fully suction to the bottom and always have a rounded R angle.🤔
The truth is, vacuum forming is a complex process that requires precise coordination between temperature control and vacuum shaping. While the vacuum shaping process is easy to observe, the subtle changes in temperature are much harder to detect. As a result, it's common to mistakenly assume that insufficient suction from the pump is the cause of this issue.😕
To address this, we decided to record a real-time video of the molding process using a thermal imager, marking three temperature detection points to showcase the temperature changes. Pay close attention to Temperature1: when the mold is placed directly on the stainless steel base plate and the 0.5mm thick PET sheet is pressed down and adheres to the base plate, Temperature 1 drops from 125°C to 78°C (the hardening temperature) in less than a second.
In this scenario, the rapid cooling process outpaces even the most powerful vacuum pump. As a result, the R angle of the formed material becomes quite pronounced!
>>>0.5mm PET attached to stainless base
If we place a wooden board under the mold, the cooling process slows significantly. In this setup, Temperature 1 drops from 125°C to 78°C over an extended period of about 4 seconds, compared to less than 1 second with the stainless steel base plate. This extended cooling time gives the pump ample opportunity to shape the material more effectively, resulting in a much sharper corner with less pronounced R angles.👍
>>>0.5mm PET attached to wooden board
By understanding the process and optimizing temperature management, you can achieve much better results. For example:
- Using a less heat-absorbing board as the base.
- Pre-heating the mold to 50°C before starting.
- Using a hot air gun during the molding process (don’t forget to set the material thickness to 3.0mm on your FORMART to extend the pump's operating time).
These adjustments can significantly improve the outcome.
Of course, if you prefer to rely on a more powerful pump to address the issue, that’s also an option. However, it's similar to upgrading a Ferrari that already accelerates from 0 to 100 km/h in 3 seconds by adding an even bigger engine to push it to 2 seconds — the cost might be far greater than you expect!😆
by Emerson
