# How do they get those aluminum inserts in the protostar?

**URL:** <https://forums.yoyoexpert.com/t/how-do-they-get-those-aluminum-inserts-in-the-protostar/357387>\
**Category:** General Yo-Yo\
**Created:** [May 16, 2022, 1:41am UTC](https://forums.yoyoexpert.com/t/how-do-they-get-those-aluminum-inserts-in-the-protostar/357387 "2022-05-16T01:41:11Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![TheBandalorian](https://avatars.discourse-cdn.com/v4/letter/t/e495f1/32.png) [@TheBandalorian](https://forums.yoyoexpert.com/u/TheBandalorian)\
**Post date:** [May 16, 2022, 1:41am UTC](https://forums.yoyoexpert.com/t/how-do-they-get-those-aluminum-inserts-in-the-protostar/357387/1 "2022-05-16T01:41:11Z")

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Just wondering, as I have no experience with bimetals or plastics with metal rings, but does YYF for instance glue aluminum rings in plastics like the protostar or do they like snap in or what? Just curious. I would think gluing would be less precise re. weight, but maybe it’s nominal….

Thanks!

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**Author:** ![kretzschmar](https://sea1.discourse-cdn.com/flex015/user_avatar/forums.yoyoexpert.com/kretzschmar/32/668707_2.png) [@kretzschmar](https://forums.yoyoexpert.com/u/kretzschmar)\
**Post date:** [May 16, 2022, 2:05am UTC](https://forums.yoyoexpert.com/t/how-do-they-get-those-aluminum-inserts-in-the-protostar/357387/2 "2022-05-16T02:05:21Z")

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I have no idea. My guess is compression fitting, basically snapping like you suggested. Again, I’m guessing.

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**Author:** ![hobby\_master](https://sea1.discourse-cdn.com/flex015/user_avatar/forums.yoyoexpert.com/hobby_master/32/145533_2.png) [@hobby\_master](https://forums.yoyoexpert.com/u/hobby_master)\
**Post date:** [May 16, 2022, 2:18am UTC](https://forums.yoyoexpert.com/t/how-do-they-get-those-aluminum-inserts-in-the-protostar/357387/3 "2022-05-16T02:18:50Z")

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Press fit