# Simple question: what is the raised bump for on the centres of the Chief's sides

**URL:** <https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893>\
**Category:** Looking for Help/Recommendation\
**Created:** [February 22, 2013, 11:39pm UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893 "2013-02-22T23:39:26Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Nagamooto](https://avatars.discourse-cdn.com/v4/letter/n/58956e/32.png) [@Nagamooto](https://forums.yoyoexpert.com/u/Nagamooto)\
**Post date:** [February 22, 2013, 11:39pm UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893/1 "2013-02-22T23:39:26Z")

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? Thanks…

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**Author:** ![dingo54](https://avatars.discourse-cdn.com/v4/letter/d/8baadc/32.png) [@dingo54](https://forums.yoyoexpert.com/u/dingo54)\
**Post date:** [February 22, 2013, 11:40pm UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893/2 "2013-02-22T23:40:03Z")

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The axle has to have somewhere to screw into, that’s where.

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**Author:** ![Nagamooto](https://avatars.discourse-cdn.com/v4/letter/n/58956e/32.png) [@Nagamooto](https://forums.yoyoexpert.com/u/Nagamooto)\
**Post date:** [February 22, 2013, 11:49pm UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893/3 "2013-02-22T23:49:26Z")

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Thanks - sorry for the daft question.

I was comparing it to the AC and noticed the AC did not have it (i thought it was for some kind of finger spin/grind thingy!?). I know nothing about grinds etc and am not even sure what and IGR is! Time to learn methinks!

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**Author:** ![dingo54](https://avatars.discourse-cdn.com/v4/letter/d/8baadc/32.png) [@dingo54](https://forums.yoyoexpert.com/u/dingo54)\
**Post date:** [February 22, 2013, 11:52pm UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893/4 "2013-02-22T23:52:34Z")

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It is actually IRG not IGR. It stands for Inner rim grind. It is the little rim towards the outside of the yoyo, where you put your thumb to grind. And no problem, you can’t learn without asking. :wink:

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**Author:** ![yoyoavenger](https://sea1.discourse-cdn.com/flex015/user_avatar/forums.yoyoexpert.com/yoyoavenger/32/884_2.png) [@yoyoavenger](https://forums.yoyoexpert.com/u/yoyoavenger)\
**Post date:** [February 22, 2013, 11:59pm UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893/5 "2013-02-22T23:59:13Z")

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IRG = Inner Ring Grinds

IGR = Inner Grind Ring

The IGR us where you do the IRGs.

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**Author:** ![Nagamooto](https://avatars.discourse-cdn.com/v4/letter/n/58956e/32.png) [@Nagamooto](https://forums.yoyoexpert.com/u/Nagamooto)\
**Post date:** [February 23, 2013, 12:12am UTC](https://forums.yoyoexpert.com/t/simple-question-what-is-the-raised-bump-for-on-the-centres-of-the-chiefs-sides/49893/6 "2013-02-23T00:12:54Z")

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Thanks for the help guys.

Now i am sure i will be going for a first run foxy moss AC as my first clyw yoyo (and also be looking at some grind tricks!).