Re: [TheThinkTank] Tricks of the Trade- unbending an axle
Many, many efforts have shown a soft-faced, deadblow hammer is a very useful tool for straightening solid axles, ala '70s vint Schwinns, while in the hub. QR axles w/ freewheels can often be straightened, though occasionally fail. In my experience, the bearing races and cones have shown no effect from the blows. In fact, this is why we now have cassettes, the drive side bearing (fulcrum) of the axle is further inboard with a FW, as opposed to a cassette, creating a longer lever (bearing to dropout) with more force.
I have found through hundreds of trials that solid unhardened steel bent, 20 degrees or less, can almost always be cold set (unbent), once, with virtually no repercussions. This applies to forks, cranks, axles, dropouts, etc. Other metals, hollowforms and repeated bending are possible, but face limitations too complex to describe, quickly. And, of course, all bending affects the strength/toughness making the material progressively weaker.
The hammer is the first and most useful tool, though you'll need glass to make sure things are straight.
Kevin The Bicycle Collective
On Wed, Oct 24, 2012 at 9:19 AM, christopher@holisticcycles.com wrote:
Sure they Park manual says that you cannot unbend an axle. And yes, working at a shop you wouldn't do that without customer permission (and maybe not even then), you'd just order a $10 axle from Wheels.
Since we have plenty of "clients" who could care less about the "right" way....Have fun trying to rebend a beefy 10mm rear axle with a hammer (small sledge maybe?) - if you're happy with the result and it works well, there are much worse things we could do the "wrong" way.
My "wrong way" example might be - replacing hub bearings with ones which "look like" the right size from the bearing bucket. Have you ever dropped those through the park ruler bearing holes? Ten brand new bearings (of known equal size!) costs about 25 cents in bulk.
Side note - some bike folk once advised me that it's not always best to use the high grade super-hard bearings, since some lower quality hubs don't tolerate them quite as well as softer bearings. Not sure I buy this in a practical sense or will ever know, but there it is...
Side note - Loose Screws is going out of business, they want to retire. <Sad face> They were nice enough to give my last collective a discount on bulk bearings. Might be an opportunity to work with them for spare parts for our community??
Brian
On Wed, Oct 24, 2012 at 10:36 AM, Kevin Dwyer kevidwyer@gmail.com wrote:
participants (3)
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Brian (SLO Bike Kitchen) -
christopher＠holisticcycles.com -
Kevin Dwyer