Day 11 Progress Check Flashcards
What is the purpose of using a vacuum forming technique in the shaping of complex curves in transparent plastics?
To ensure uniform thickness and strength of the plastic.
During the cleaning process of transparent plastics, why should harsh chemicals be avoided?
They can cause crazing and weaken the material.
Which of the following is a key consideration when installing windshields to ensure proper fit and performance?
Using gaskets and mounting hardware to distribute stress and ensure waterproofing.
Which of the following steps is NOT recommended during the cementing process of transparent plastics?
Applying cement at temperatures below 65°F.
In the context of transparent plastic repairs, what is crazing?
The formation of fine cracks on the surface due to overstressing.
When storing transparent plastic sheets, why should they be kept away from direct sunlight?
To prevent adhesive deterioration and potential damage.
Which type of cement is commonly used for its clear, stable joints in transparent plastic repairs?
Polymerizable cement like PS-30®
Why is it crucial to maintain the protective masking on transparent plastic sheets for as long as possible?
To prevent surface damage during handling and storage.
What is the primary reason for avoiding direct heating methods like hot water or steam when forming transparent plastics?
They cause uneven heating, leading to potential material stress and deformation.
What is a crucial safety consideration when cutting and drilling transparent plastics?
Using high-speed, low-feed rates to prevent heat build-up and material damage.
Which forming technique is recommended for creating simple curves in transparent plastics?
Drape heating over a form and allowing to cool without forcing.
What is the primary disadvantage of using thermosetting plastics in applications requiring reshaping?
They cannot be remelted and reshaped once set.
During the repair of minor cracks in transparent plastics, what is the purpose of drilling holes at the ends of the cracks?
To prevent further propagation of the cracks.
Which military specification applies to craze-resistant acrylics used in aircraft windows and canopies?
MIL-P-8184
Which of the following statements best describes the primary difference between thermoplastics and thermosetting plastics?
Thermoplastics can be remelted and reshaped, while thermosetting plastics cannot.