Chainring fabrication methods
#1
Chainring fabrication methods
Hi All, so I have this unused Suntour 12 tooth track cog that I'd like to use on an IRO frame that I'm likely to buy. 12 is small, and will require a 36 tooth chainring to get me desired gear inches. With a ring this small, I want to ensure that it is VERY round. I'm looking at a FMF "power series" chainring, which is CNC machined aluminum. I read Sheldon Brown's article on cnc machining vs forging (https://sheldonbrown.com/dp-forging.html). It was enlighterning, but didn't answer my main question: does CNC machining ensure a very round ring? It seems that it would be less strong than a forged ring, but would it be equally round? How are chainrings made that aren't CNC or forged, and how do they get to be less round?
Thanks folks
Thanks folks
#7
Senior Member


Joined: Feb 2004
Posts: 30,225
Likes: 649
From: St Peters, Missouri
Bikes: Catrike 559 I own some others but they don't get ridden very much.
Relative to roundness the real trick is getting it mounted onto your crank spider so that it's perfectly concentric.





