The Chainlink

Damn Cottered Cranks...

OK, so I have two bikes with seized cotter pins on the cranks that I am planning to use for my new tall bike and I CANNOT get the bastards out.  A king pin press just massed and bent them over and I have tried heat plus a hammer and punch until my hands hurt but they are not going anywhere.  I really do not want to cut the cranks up, they are cool old ones that I want to reuse, any hints?

Thanks!

Views: 98

▶ Reply to This

Replies to This Discussion

Permalink Reply by Tank-Ridin' Ryan on June 16, 2010 at 5:27pm
Permalink Reply by mike w. on June 16, 2010 at 6:41pm
i assume that you've soaked the snot outta 'em with liquid wrench? Sometimes you've just gotta wail on them. What we used to do at the old shop was the penetrating oil soak, chop the threaded end off with a cold chisel (assuming that that bit's already roached,) brace the backside of the arm with 2X4, and get Big Jerry and his 5lb maul and punch to blast away while we held the bike steady.

Maybe someone out here has a VAR or Parks cotter press?
Good luck. HTH
Permalink Reply by mike w. on June 16, 2010 at 6:43pm
Also i'd try the heat treatment once more.. get 'em glowing. i doubt you'll damage them much more.
Permalink Reply by Arrak Thumrs on June 16, 2010 at 7:04pm
Sometimes, you just have to let certain things go...
Or rig up the drill press, but then you'll be fabbing new tapered holes on your arms. Do you really want all that work? I could drill them out, but you'd have to drop them off here in the western burbs.
Permalink Reply by Shay on June 16, 2010 at 8:54pm
I have absolutely no fucking clue what any of you are talking about, but it sounds fascinating. Carry on!
Permalink Reply by Arrak Thumrs on June 16, 2010 at 10:04pm
Haha! Get out the thingamabobber and jam in the schnoozledammer---don't forget the funker! If that doesn't work, time for the grabbitz quibbley... :)

http://www.sheldonbrown.com/cotters.html
Permalink Reply by wig [ isaac ] on June 16, 2010 at 10:52pm
cut cut cut....... the time your wasting trying to save cranks you have " hammered the snot out of " are fucked... now cut them off and build your dream...
Permalink Reply by Doug Haynes on June 16, 2010 at 11:41pm
The cranks are not hammered, I know how to hold a punch and swing a hammer...

I am holding off on cutting them because I want the Raleigh chain ring on the tall bike. I'm just going to try more heat and see what happens, if I deform or anneal the strength out of the cranks so be it.
Permalink Reply by Michael Perz on June 17, 2010 at 8:49am
I've never worked on cottered cranks, but my guess is that heating the cotter is causing it to expand faster than the crank. Is the crank steel or aluminum?
Permalink Reply by Doug Haynes on June 17, 2010 at 9:17am
Crank is steel and I am heating the crank not the pin.
Permalink Reply by Tony Adams on June 17, 2010 at 9:30am
Arrak Thumrs said:
Haha! Get out the thingamabobber and jam in the schnoozledammer---don't forget the funker! If that doesn't work, time for the grabbitz quibbley... :)

http://www.sheldonbrown.com/cotters.html

Like we all just happen to have schnoozledammers laying around in our shops anymore!
Permalink Reply by John on July 3, 2010 at 2:33pm
I only mention it because I have done it myself - trying to remove the crank on the drive side, having forgotten that it is permanently attached. I have no idea why there are cotters on both sides when one crank isn't going anywhere.

Garth has a cotter pin press; other than that, I would drill because the pins are softer than the crank. Now I have to get back to one of my own so I can get a nicer chain wheel and cranks on my old Humber. . .

RSS

Groups

© 2008-2016   The Chainlink Community, L.L.C.   Powered by

Disclaimer  |  Report an Issue  |  Terms of Service