Re: [CR] Restoration: Alloy parts. Question?

(Example: Framebuilders:Jack Taylor)

From: "kevin sayles" <kevinsayles@tiscali.co.uk>
To: Ken Freeman <kenfreeman096@gmail.com>, <haxixe@gmail.com>
References: <04AF769693E34512AF03DE127BBCA9D8@NormPC> <75d04b480911130834g1d1d4536k96efc0899762ff74@mail.gmail.com> <7543b4a40911140431w230146bfwfb198aa7c9a4c46b@mail.gmail.com>
In-Reply-To: <7543b4a40911140431w230146bfwfb198aa7c9a4c46b@mail.gmail.com>
Date: Sat, 14 Nov 2009 13:17:41 +0000
Cc: classicrendezvous <classicrendezvous@bikelist.org>
Subject: Re: [CR] Restoration: Alloy parts. Question?


Hi Ken, You wrote > Similarly brake calipers and crank arms/spiders had a matt finish that is
> similar to an anodized surface, but were not anodized. I don't know how
> the
> finish was achieved: simply a fine casting finish, or a tooled operation
> that did not leave tool marks, or perhaps a bead-blast of some sort.
> There
> was some luster, but not a mirror finish. It's not right to mirror polish
> them

I believe the Nuovo Record brakes, cranks & rings WERE anodised, as was the rear gear, but strangely the one component that perhaps should have been anodised wasn't...the front gear! Hubs, gear levers, pedal bodies [not the black alloy cages] were all un anodised.

I think your right in saying.....its not right to mirror polish them.....sometimes things look nicer when clean, bright and shiny, but not to the extent that alluminium resembles chrome!

This issue of restoring components is of a simular vein to whether to restore paint or not......personally I like to see my own 'vintage' stuff presented as best as possible, I don't mind a bit of 'patena' and aging, but if it's possible to clean up and present in a 'almost as new' state then so much the better.

cheers
Kevin Sayles
Bridgwater Somerset UK


----- Original Message -----
From: Ken Freeman
To: haxixe@gmail.com
Cc: classicrendezvous
Sent: Saturday, November 14, 2009 12:31 PM
Subject: Re: [CR] Restoration: Alloy parts. Question?



>I realize this was not the question, but many CR-correct aluminum parts
>were
> not originally mirror polished, so "restoring" them in this way is not an
> act of restoration but of artistic license. Examples: the Campy Nuovo
> Record parts. Some,like the seatposts, were sand-cast and have retained
> the
> sand-cast texture. The clamp area of the seatpost retains its sand-cast
> texture. The shafts are very finely finished, but it was a very
> high-quality machined finish, probably lathe-turned. Not mirror polished.
>
> Similarly brake calipers and crank arms/spiders had a matt finish that is
> similar to an anodized surface, but were not anodized. I don't know how
> the
> finish was achieved: simply a fine casting finish, or a tooled operation
> that did not leave tool marks, or perhaps a bead-blast of some sort.
> There
> was some luster, but not a mirror finish. It's not right to mirror polish
> them.
>
> It is (imo) right to perform certain filing operations that should reduce
> cracking and crankset failure. Had I known of this problem back in the
> day
> I'd have radiused the sensitive areas, so I feel it is plausibly correct
> to
> do so now, to enhance the durability of my bike.
>
> On Fri, Nov 13, 2009 at 11:34 AM, Kurt Sperry <haxixe@gmail.com> wrote:
>
>> Polishing unanodized aluminum to a mirror finish doesn't require a lot
>> of sanding steps. You can quickly sand out any pitting or scratches
>> with 220 grit dry then go straight to the buffing wheel. Start with
>> bobbing compound on a cotton wheel and follow that with Fabuluster.
>> Use two different wheels, the polishing compounds are available
>> through any large jewelry supply house. You can get a less bright but
>> shinier than satin finish by stopping after the bobbing step. I
>> always cringe when I read people describing how they went through
>> multiple hand sanding steps over hours to get what is probably not as
>> good a polish as I can get in a few minutes. Careful with the buffing
>> wheel though, it's dangerous.
>>
>> Kurt Sperry
>> ms , hubs etc. For the most part I leave anodized parts alone. For non
>> anodized parts I wet sand with grits up to 2500 and buff with Tripoli
>> compound and white rouge. What I'm wondering is there any equivalency
>> scale
>> to correlate the various abrasive media. Is Tripoli finer than 2500 grit
>> paper, where do the steel wool grades "0", "00" etc fit in.
>> >
>> > It would be helpful to know the equivalency in order to know when to
>> stop the tedious sanding and move on to the easier to apply buffing
>> compounds. Does such a correlation scale exist? For those of you who also
>> polish parts what have you learned? What do you use for a mirror finish?
>> For
>> a satin finish? Opinions welcome.
>> >
>> >
>> > Norm Lafleur
>> > Ashfield, Massachusetts
>> > USA
>> > _______________________________________________
>> >
>> _______________________________________________
>>
>

>

>

> --

> Ken Freeman

> Ann Arbor, MI USA