Tuesday, April 27, 2010

Save The Wheels

About two weeks ago, I made a pretty boneheaded error when I was removing a freewheel.

The way I remove a freewheel is to secure the freewheel removal tool a bit loosely on the freewheel with the quick release skewer.  I then position a one inch box wrench in the wood vise at the end of the bench, insert the freewheel tool into the now well secured box wrench, and turn the wheel like a big bus steering wheel.

Most of the time this gives so much leverage that the freewheels just spin right off.  However, this wheelset had been subject to a lot of 28 chainring/34 cog hauling my not insignificant butt plus a trailer full of kid, picnic supplies, and the kitchen sink up many, many hills and over many many miles.

So that freewheel was on there and after struggling with it for a good long while, I almost gave up, but finally about fifteen minutes of grunt work did the trick.  I was so relieved at this I spun it a few turns and was idiotically wondering why it was getting hard to turn again. 

But flush with the initial victory I persevered until that dreadful realization dawned on me that I still had the quick release in place.

After removing the freewheel, I made a couple of unsuccessful attempts over the past several weeks to remount a freewheel, but even though the threads looked quite good, apparently I had munged up some of the initial engagement section on the hub.  Try as I might, I just couldn't get a freewheel threaded correctly.

And these weren't just any old wheels.  The rims are nothing special, just some polished Sun CR18, but the hubs are a nice set of Campy Croce D'Aune 36h that I've been very fastidious about repacking and consequently have many years of service left.  Back in the day when I bought these, people were practically giving them away, but they are pretty spendy now.

The reason I was mucking around with the freewheel in the first place was that this was my first choice for a wheelset for the 1972 Fuji Finest over which I'm currently obsessing.  But since I had apparently screwed the pooch with the Croce wheels, I put a nice set of wheels with Campagnolo high flange Nuovo Tipo wheels on the Finest.

I also have been making my peace with ruining this rear hub - the past few days I felt like I was getting to the acceptance stage.  I've never ruined a hubset before while working on them, especially such a nice one with such a stupid move, so this was a bit of a bitter pill.

But I hadn't accepted this fate because this evening I was overtaken with a grim determination to give it one last try.  I assembled my materials, took a five deep "serenity now" breaths and headed out to the garage.

To prepare the hub, I cleaned and then carefully burnished the hub freewheel threads with a stiff toothbrush until they positively gleamed.  Then I located two english threaded bottom bracket lock rings, one tight fitting, the other loose fitting - I was fortunate to have such a selection available.

Then with the loose fitting lock ring, I started carefully attempting to thread it onto the hub.  This was like being a safe cracker, first turning counter clockwise until I thought I felt a little bump that would indicate the thread ends of the lockring and hub had just passed by each other.

That was the sign that the two pieces were oriented to start turning clockwise and threading them together.  At this point, I could maybe turn the lock ring a quarter turn before moderate hand pressure was insufficient to turn any further.  I looked carefully at the orientation of the lockring to hub to help gauge whether it was cross threading or not.

I repeated this several times until I was convinced that I had things properly set up.  Then I took a bottom bracket lockring spanner and began every so gingerly giving the lockring a little pull and deciding from the tactile feedback whether the lockring was indeed properly threaded.

As with the hand threading, I backed out of this completely several times before I was satisfied with the thread engagement.  Eventually, I worked it through a full turn or so with the spanner, after which the lockring spun the rest of the way onto the hub with only finger pressure.

Having to only use finger pressure for all but the first turn was an especially good sign that the hub was salvageable, as this, in combination with the good appearance of the threads, indicated that the thread damage was limited to the first thread course.

After another burnishing and cleaning of the hub threads, I successfully repeated this meticulous process with the tightly fitting bottom bracket lock ring.

My spirits were rising, then, as I then went for the full enchilada with a freewheel with excruciatingly cleaned threads.  I was also a bit nervous, since on initial engagement, it is harder to visual judge the line up between the hub and a freewheel than it is with a lockring.  It is also a lot easier to inadvertently damage threads with a big heavy freewheel than it is with a tiny little lockring.

But to my overwhelming joy, on first attempt and only using finger pressure, the freewheel spun onto that hub like the hub just came out of its factory packaging (with a little grease applied to threads first, naturally).

So here is wheels saved by a last minute stay of execution on the Finest.  Readers who have been following the Finest saga may note that I've been fitting up some fender and to popular acclaim have gone with steel braided brake cable housing.  Better pictures will be forthcoming in future posts:

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