Updated a 1.2mm thickness version, better print with PETG

更新了一个1.2mm厚度的版本，最好使用 PETG 打印

I found that the phone cases available on the website were too thick, bulky, and lacked bottom protection. Additionally, due to issues with the opening shape and interlayer adhesion of the material, they tend to crack easily after inserting the phone.Therefore, after a whole day of modifications, trials, and test prints, I have achieved the best version so far. I have made the following improvements:

• Reduced the overall thickness of the shell, from the original 2mm to 1.5mm for the borders and from 3.5mm to 1.5mm for the bottom.
• Changed the bottom design from an open style to a fully enclosed style, carefully adjusting the openings for the microphone/speaker and Type-C port.
• Fine-tuned the gap between the shell and the phone, slightly increasing the length to account for material shrinkage, achieving an easy insertion while maintaining a snug fit.

Printing guidelines:

• Please use a layer height of 0.1mm, 3 walls thickness, and increase the number of bottom or top layers. Avoid using sparse infill.
• You can slightly increase the temperature by 5-10 degrees to enhance interlayer adhesion, especially when using matte/semi-matte materials.
• I have added three manually removable supports for the openings. You can also try printing a partial model to test the bridging effect. If satisfied, the supports can be removed.

我发现网站上现有的手机壳都太厚太笨重并且底部没有保护，并且因为开口形状和材料层间粘合力的问题，导致容易在放入手机后开裂。于是我通过一整天的修改尝试并测试打印了五六个版本，这是目前最好的一个，我做了如下改进：

1. 整体缩小壳体厚度，边框由原来的2mm缩减到1.5mm，底部由原来的3.5mm缩减到1.5mm
2. 底部由开放式设计改为全包设计，仔细调节了麦克风/扬声器和Type-C的开口
3. 微调了壳体与手机的间隙，并考虑到材料收缩的特性略微加大了长度，以达到可以轻松放入但又非常贴合的效果

打印注意事项：

1. 请使用0.1层高，3层壁厚，增加底部或顶部层数，不使用稀松填充
2. 可略微添加5-10度温度以增强层间粘合力，特别是在使用磨砂/消光材质的材料时
3. 我添加了三个开口的手动支撑，你也可以尝试打印局部模型测试拉桥效果，若满意也可去除支撑