Sunday, September 23, 2007

Odds 'n Ends

Since dropping frames off for paint, I've been moving a little bit slowly in the shop and getting in a few more miles on the road. The next two weeks may be more of the same as we are going out of town next week for a long weekend to attend a wedding. Still, there are a few things to share which you may find of interest. Hence, Odds 'n Ends.

First my Stein Stronglight crank-puller arrived along with a VAR that works on modern cranks and older TAs (another unique crank thread). So the Path Racer is fully torn down and I'm working on final surface prep, but probably won't get this to the painter for 2-3 weeks.

Using the Stein/Stronglight puller, the fit is very tight. So much so, that I stopped installing it, and tried the VAR/TA. The TA is too small. It threads in nicely, but has a very loose fit, which worries me about damaging the threads. So, I reverted to the Stein/Stronglight and used a wrench to turn it in. The crank pulled out easily and it wasn't too difficult to remove the puller. But a small sliver of aluminum fell out while removing the puller, which has me a little concerned. I think I'll contact Stein before using this on my Stronglight 49 crankarms.

Having pulled the Stronglight 93 arms, I tried doing a little polishing on the right arm. Most of the face cleaned up nicely, but these was a spot that wouldn't come out (I'll have to post some pictures). My guess is that something got on the arm and caused some corrosion, leaving a small area with a pitted surface. I tried sanding the area, and then filing it lightly. But neither will get to the bottom of this pitting without changing the contour of the outer face of the crank. I guess I'll have to do some research on methods to repair this surface.

A new set of Velo-Orange fenders arrived this week (for the Path Racer). They appear very well formed, and of reasonable weight. The stays are good, as is most of the hardware. On the Velo-Orange site, it's noted that the fork attachment isn't as nice as the one that comes from Honjo. But, I find that, half the time, I need to fabricate a custom attachment anyhow, so that doesn't concern me very much.

These fenders cost about 1/2 of the comparable Honjos, but they come unfinished. The raw aluminum sheet is formed, packaged, and shipped. I did some test polishing on one of these fenders to see how hard this would be. I put a buffer in the drill press, running at its highest speed (3150 RPM). First I tried Simichrome polish. I does a nice job, to a point. The fender become shiny. But, there are some typical imperfections in the aluminum that it doesn't easily address.

Next up was some buffing compound (designed for steel). I have several, including one that is courser for cutting and one that is finer for polishing. Even the finer compound did a better job than the Simichrome at removing the surface imperfections. And, I couldn't see improvements in the finish after applying Simichrome on top of the area that had been worked with the buffing compound. My guess, is that it'll take me about an hour per fender to polish them to a satisfactory state.

I was concerned about the durability of the polished surface - would it oxidize, discolor, whatever? After doing a bit of research, it appears that a thin oxide layer quickly forms. This layer protects the underlying aluminum and generally looks fine. So I'm going to try going without any overcoat (Shellac, clear-coat, whatever).

Well, that's it for now. See ya next time.




2 comments:

Unknown said...

Howdy,

Would you be willing to e-mail me when you hear back from Jim about the Stronglight puller?

Thanks either way!

Ross

Rick Guggemos said...

Jim sez there are production variations in the tight/snugness of threads on the cranks (seems believable). He recommends trying a little grease. If that doesn't work, he's willing to look for a puller with a looser fit and swap for mine.