1) Longer with the bigger grits, less with the smaller but yeah, 2-3 minutes with each. When working with the bigger grits I'll do more "cross sanding"...sand one direction for a while, then the other...I think the paper cuts quicker doing that. But agreeing with miamijim, last strokes should always be long with the part.
2) I've not yet, but that will happen someday. I do refresh the brake tracks on rims with the abrasive ball. Clean 'em up, then a quick pass with the medium ball.
3) No gloves. Citrus-based hand cleaner from Northern Tool (need some too, thanks for reminding me)
It’s been a while since I wrote my original aluminum polishing methods back on Thanksgiving 2010. Since then I’ve been, of course, polishing lots of parts. I have refined my steps somewhat in the ensuing six months or so and thought I’d post an update.
The basic steps haven’t changed:
- Deanodize (if needed)
- Sand Out Flaws
- Sand For Smoothness
I’ll add my comments per step below.
Lately I haven’t been using Easy-Off spray. It really throws a lot of lye out in the air in I simply hate that. What I have been using is simple kitchen drain cleaner crystals, the particular ones are made by Rooto and I got them at Ace Hardware:
I’m sure anything equivalent would work as well. I’m still playing with the strength and it depends I guess on how quick I want to deanodize but maybe 2T per gallon. I do bubble the aluminum on occasion. I’ll soak the part a minute or so, pull it, rinse, wipe with a rag, and repeat until I’m satisfied that all the anodizing is gone. I think the anodizing varies so much it’s hard to say how long to do it…you just have to play with it.
Sand Out Flaws
As of late I’ve become absolutely SOLD on Norton Black Ice waterproof sandpaper. I simply love the stuff. It lasts a VERY long time, it sands beautifully, and cuts fast:
You’ll probably need to find a local auto paint/finishing store to find this…or online. This paper will not be a typical big box store or hardware store item. It is more expensive, be prepared, but I honestly don’t think there’s a comparison between this and the other papers I've used.
For sanding out flaws I’ve been using the 320 grit Black Ice paper and the Norton dual density sanding pad:
I take 1/6 sheet, wrap around the pad, and work the flawed areas. I use the denser black side initially and as the last bit of the flaw is coming out I switch to the softer gray side. As always you have to be careful about very intense spot sanding, which can leave valleys that can be seen after polishing. I think this pad is just stiff enough to let you apply some focused pressure but deflects enough to give a nice smooth transition on the surface.
Sand For Smoothness
Once the flaws are gone, or as gone as I dare make them, I switch to the new grit progression I use since using the Black Ice paper: 600, 1200, 2500. Yep, three grades. I can’t do this with paper other than the Black Ice because of how evenly and quickly it cuts. Wet sanded of course.
I’ll use the sanding pad with the 600 but the 1200 and 2500 I’ll use by hand. The 1200 and 2500 when wet become very flexible, it’s almost like wiping the part with an abrasive rag. The 2500 especially. Regarding the 2500 grit. If you take enough time with it this could be your final finish. The more time you take with it the less you'll take with your polish.
On a part like a seatpost I’ll spend barely 10 minutes total with all three grades.
Nothing new here, Mothers is still my favorite…it produces a beautiful shine. However, I have been using Blue Magic for the last polish. I think it puts just a slightly blingier shine on the part. It also “Provides lasting protective coating…”
Anyway, that’s my update. I think the addition of the lye crystals and the Black Ice sandpaper has dramatically cut down the time it takes me to finish a part. Find and try the Black Ice sandpaper. I think you’ll see what I mean after about 30 seconds.
Last edited by khatfull; 08-07-11 at 03:24 PM.
No new before and after pics!?!?
53.5 cm Cinelli / Centurion Project Frameset FOR SALE - PM or email me. Also have Campy 9 and 10 speed Chorus and Record alloy parts, Campy 50th seatpost, etc. to go with it.
Ok, I sucked it up last night and did a quick job on that Campy post. Let me preface this by saying there's a little more work to do here but I think you'll get the idea. Also, it is hard to photograph differences in the finishes.
Here's the post before. Someone or the eBay seller had done an amateurish job of trying to smooth it and get rid of jaggies:
Pretty icky huh? Alright, here it is after flaw removal with 320, the pass with 600, and smoothing with 1200. Also, to demonstrate something else I took the 1200 grit, held it around the post and twisted the post. Not moving up and down at all while turning, just twisting the post in the paper. Finish an area, then remove the paper, move to a new area, then twist again. It leaves a semi-machined look at a lot of people might want to go for. If I was doing this for real to leave the finish like that I'd use 800 grit. That leaves visible scratches around the circumference as if the post had been freshly machined. You could experiment with different grades until you get what you want. This 1200 grit finish looks nearly polished but doesn't reflect as a mirror.
After taking the above pic I used the 1200 again along the length of the post to smooth again then went over it with the 2500 grit. I do have a little work to do up at the the top by the Campy logo and I don't pay as much attention to the area below the minimum insertion line for obvious reasons. Again, this is was a very quick job to demonstrate the "new" method, pay attention to the middle section of the post. Below is after the 2500 grit, about three minutes with the 2500 I'd imagine.
As you can see the 2500 does leave a shiny finish. It is devilishly hard to get even though, if I can figure out how to do that the 2500 grit on it's own could be a final finish. And below, after a few minutes with Mother's and Blue Magic:
As you can see it is possible to get pretty much a dead mirror finish with just sandpaper and polish. My SR post is even prettier .
Anyway, I didn't want to wait until after vacation to throw up some pics, so I did this quick. 4Rings6Stars I hope this answers some questions.
I think I may have asked before, but don't remember the answer, if there was one.... How long does a mirror finish like that last before it oxidizes and needs another polish? Is there a way to preserve the mirror? Maybe clear coating it?
Mother's doesn't mention any kind of protective coating but Blue Magic does which is one reason I end with it. Whther that's true or not I don't know.
What I do know is this. Once a part has been brought to this condition even if it does oxidize a bit it could be made shiny again in very short order with a quick polish. The time investment is in the flaw removal and all the smoothing. Once polished REpolishing is easy.
i hear 7000 series aluminum oxidizes faster than 6000 but i have no factual data to back it up.
This is such an excellent primer on polishing and how to properly cook a turkey... I should share my little recipe for spinach and feta stuffing which will make most people swear off that wheat based stuff.
I use very similar steps but also have a few tools and skills in doing extremely fine work... used to have a need for 12,000 grit specialty discs for some work that had to be done under a loupe so find bike parts are much easier.
On that note, I have restored the engraving on a number of items that were considered write offs aesthetically but of course, never think to take a before and after.
I do have a good number of Vx derailleurs and think most would be hard pressed to tell which one of them got dragged along a section pf pavement during a crash (not me) unless they were looking at things very closely.
People sometimes mistake some of the aluminium parts on my bikes for being stainless or chromed and it is the same process of graduated sanding followed by mothers and a light wax and sometimes I use some of the small buffers for my dremel or die grinder to hit small crevices.
We have quite a few buffers and some things can get chucked into the lathe... we use that to get some very bright polishes on our hubs.
Now that the Minnesota winter is starting I should polish something, put it out on the deck railing, and take a pic every two weeks. Hmmm...
Thanks for renewing this thread. I've got a Sugino crank that I'm going to clean up and put a nice polish on. Paced the bid before making another trade here on BF's for a better triple crank, ended up winning it on the minimum bid, so I suspect it will end up on the VeloBase Marketplace sooner or later.
I have a Harbor Freight near me, and I think I will go looking for an "abrasive ball". A timely thing, this thread popping up when it did. I am just about to polish the Nervar Star crank on my Moto GR. I don't have the chainring bolt wrench at home, so I am bringing it to work for disassembly and eventual polishing. I did a little by hand, but it just not up to what I wanted.
I could do some serious polishing at home in Houston, with all the tools etc. Now I am in a one bedroom apartment, and even my DeWalt cordless drill is completely dead. Replacement batteries are $90 each!?! I may just use the drill at work next Saturday when I am off. If anything it will give the younger coworkers a glimpse of the dark side. I mean refurbishing vintage bikes of course.,,,,BD
He did a quick pass with the abrasive ball on the GB stem he sent me a while back, and it looks factory fresh. Sorry Keith, my camera battery is dead, but I will get a pic of it on here tonight if I can.,,,,BD
I use the coarse for buzzing off shopwear, the medium after that, and the fine for getting the initial smooth finish before starting with 600 grit wet/dry.
Those were: deanodize with lye (I masked off the top of the post, the textured part and only lowered into the lye just below that), 600, 1200, 2500 Black Ice wet/dry, Mother's, final pass with Blue Magic. I would guess 1.5 hours total for the pair.
green ball. I might have been using a worn one too. In all the grades, they;re much more aggressive the first few times you use them, then they kind of soften a bit...
EDIT: I should add...when I do things like stems and hub shells I'll actually take the ball apart, remove some layers leaving 2-4 layers of the abrasive material, then space back with washers and reassemble. That makes it MUCH easier to get into and control inside hubshells and the inside part of the crook in a stem.
On and off topic, how to you adjust the seatpost without getting the zig zags?
2) CLEAN seat tube.
3) Greased seat tube.
4) Be sure clamping area isn't pinched.
5) Check slot by clamp to be sure there's no burrs on the inside of the tube. If so I use a Dremel and a sanding drum to just lightly buzz the inside of the tube right at the slot. Then a pass with fine sandpaper.
The post should move up and down fairly easily with moderate pressure and without twisting.
Nice writeup here. I'll recommend getting a set of Micro Mesh sanders. I use them instead of wet sand paper. I've had the same set for a few years - they are flexible, strong and last forever:
The man who dies with the most toys…is dead. - Rootboy