How the flatten a chainring?
#1
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Steel is real
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From: Australia
Bikes: Custom - Record Vortex 8 spd Nexus & Mistral Le Mans 3 spd Shimano. Giant Kronos. Raliegh Single Speed
How the flatten a chainring?
It is slightly bent, any ideas how to panelbeat it straight?.. would be appreciated.
I was going to use a 48 tooth single chainring for a road bike 700c wheels 8 speed nexus 15 sprocket, but i'm guessing it would be way too tall
this was on the frame i'm using when i got it, have the matching peddle arm for the other side, i quite like the look of it.. so would like to use it for that reason as well, it's 42 teeth

I was going to use a 48 tooth single chainring for a road bike 700c wheels 8 speed nexus 15 sprocket, but i'm guessing it would be way too tall
this was on the frame i'm using when i got it, have the matching peddle arm for the other side, i quite like the look of it.. so would like to use it for that reason as well, it's 42 teeth

#8
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Steel is real
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From: Australia
Bikes: Custom - Record Vortex 8 spd Nexus & Mistral Le Mans 3 spd Shimano. Giant Kronos. Raliegh Single Speed
Good idea, you could get that pretty precise using a guide of some sort, cheers
Last edited by le mans; 02-07-19 at 12:36 PM.
#9
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Steel is real
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From: Australia
Bikes: Custom - Record Vortex 8 spd Nexus & Mistral Le Mans 3 spd Shimano. Giant Kronos. Raliegh Single Speed
The mind boggles how it dished out a bit, and bent out a bit more in one section?
#10
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From: NW,Oregon Coast
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Not a thousand Wordsworth *
You riding it when you high sided & hit something? have a flat surface for comparison to know its perfect again ? say a Granite counter top?
have to put it on a BB spindle and rotate it with a fixed reference point for comparison (Like a Front Derailleur ) or your lathe tool rest..
yea pencil OK, but have to put the crank on the bike first...
holding it in the air against a blank background mostly demonstrated you has a camera no un flatness was to be seen ...
*other than computer code for the image..
....
have to put it on a BB spindle and rotate it with a fixed reference point for comparison (Like a Front Derailleur ) or your lathe tool rest..
yea pencil OK, but have to put the crank on the bike first...
holding it in the air against a blank background mostly demonstrated you has a camera no un flatness was to be seen ...
*other than computer code for the image..
....
Last edited by fietsbob; 02-07-19 at 12:06 PM.
#11
Thread Starter
Steel is real
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From: Australia
Bikes: Custom - Record Vortex 8 spd Nexus & Mistral Le Mans 3 spd Shimano. Giant Kronos. Raliegh Single Speed
no it's something i collected, there's a scratch on the top tube so it must have been hit
high sided? well.. there ya go
but, after cold bending the dropout to suit the hub, the frame alignment is fine, very solid frame (Indi Australia)
"have a flat surface for comparison to know its perfect again ? say a Granite counter top?"
that centre fitting gets in the way, what holds the chainring & arm together, unless i find a flat surface with a hole in it
high sided? well.. there ya go
but, after cold bending the dropout to suit the hub, the frame alignment is fine, very solid frame (Indi Australia)
"have a flat surface for comparison to know its perfect again ? say a Granite counter top?"
that centre fitting gets in the way, what holds the chainring & arm together, unless i find a flat surface with a hole in it
Last edited by le mans; 02-07-19 at 12:24 PM.
#12
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Steel is real
Joined: Dec 2014
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From: Australia
Bikes: Custom - Record Vortex 8 spd Nexus & Mistral Le Mans 3 spd Shimano. Giant Kronos. Raliegh Single Speed
found it wasn't all dish outwards, one section was bent inwards, didn't take long to fix!
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