I'm well aware of using powered methods. I have a 36" wide buffer with 12" buffing wheels on each side and Menzerna compound. The point was for the do-it-yourself-er that doesn't have these things and is in no hurry. Yes, it's more work but I found it pleasureable to work on a certain part for a while and then stop when I felt like it.
My point about optically flat comes into the powered method. It's tempting to apply more pressure and create divots to speed things along with the rough compounds. I use a series of different blocks to hold the paper (a small piece of corian, a popcicle stick, a Sanding Stick with 400 grit, etc) and make sure I'm not making peaks and valleys. The difference, particularily on large flat surfaces, is the same difference as a quality mirror and the fun mirrors you see at the carnival:-)
Someone asked about anodizing small parts. Most anodizing shops (look in the yellow pages under anodizing) have a minimum. I paid around $20 for small parts in any color. The shops then wait for a batch to come in and they add your parts to that batch. If you have polished surfaces or precision surfaces, make sure you ask for "light etch". This means they leave the parts in the first acid etch for the minimum length of time, reducing the amount of material that's removed, and hence, the less surface damage. Most shops have clear, black, red, green and blue as standard colors (dyes that are added to the bath). I expect most here want just clear.
Gary
________________________________
From: Kurt Sperry [mailto:haxixe@gmail.com] Sent: Monday, December 18, 2006 4:24 PM To: Watts, Gary J (Vancouver, WA USA) Cc: classicrendezvous Subject: Re: [CR]Polishing aluminum parts
Going through all those sanding steps is wholly unnecessary for getting a spectacular mirror polish on most commonly used Al alloys. After 400, go straight to Bobbing compound, a medium abrasive in a wax matrix, on a 8" or so cotton buffing wheel ~1,500 to 2,500 rpm, then use Fabuluster (spelling might be slightly off) on another cotton buffing wheel. Done. It should only take minutes on the wheel. The resulting finish will be every bit as brilliant as going through the whole gamut of abrasive papers and take exponentially less time and effort. Once degreased, at this point if desired the parts can be reanodised clear and the polished areas will look exactly as they did new- perhaps better- if they began as anodised bits like Cinelli stems or Campagnolo crankarms or calipers with that lusturous silver satin finish.
Kurt Sperry Bellingham WA USA
On 12/18/06, Watts, Gary J (Vancouver, WA USA) <gary.watts@hp.com> wrote:
I got a fair number of questions about the polishing method I
used on
the Colnago Super Campy parts. I thought I'd post that
information here
for anyone that is interested.
=09
Ray Dobbins is to blame for "baiting" me with the beautiful
examples of
polished parts on his webpage such as his Molteni replica:
=09
http://www.raydobbins.com/
He also has a useful page on polishing of his own, using a
machine
buffer here:
=09
http://www.raydobbins.com/
The list there is good for knowing what parts will need to have
the
anodizing stripped first.
=09
I used the Easy-Off method (contains lye), leaving it on for
5-10
minutes. This is not needed on non-anodized parts.
=09
Many of the parts had dents, scratches and other surface
abnormalities.
Polishing will make the part "shiny" byt not optically flat.
This is
very visible on flat surfaces.
=09
1) Strip off the anodizing
2) File or sand out all imperfections. The exact method will
depend on
where and how deep the issues are.
3) Start working through the various grits. I used 220 (Silicon
Carbide
paper like 3M wet-N-Dry, the black stuff)for the big offenders
after
filing, followed by 400, 600, 800, and 1200. After this, I
started the
Micromesh papers going up to 3600.
4) Polish with Simichrome polish. This is great stuff and is
best hand
applied.
5) I applied a coat of liquid carnuba wax (Meguiars or Mothers)
to
provide some simple protection.
=09
Patience is the key and not skipping grits. You'll get a mirror
if you
follow the steps.
=09
Gary Watts
Vancouver, WA
USA
_______________________________________________
Classicrendezvous mailing list
Classicrendezvous@bikelist.org
http://www.bikelist.org/