Guide Guide: Polishing Aluminium

Hello folks, here’s my new guide for you all, how to polish Aluminium for that ‘I Can’t Believe It’s Not Bu... Chrome’ Shine.

First, here’s what I’m going to polish, a Cool-Matic X850 graphics block cooler top.


Number one, prepare the surface, put the block in a vice/workbench to hold it, we don’t want any accidents here do we?


I used a flap wheel to get rid of the logo and the anodising, not necessary if you don’t have anything on the surface of the aluminium like paint.


You can see the difference between the anodised surface and the sanded surface.


Here’s the finish after the flap wheel. A bit rough but could pass as brushed aluminium at a distance.


Next is the 400 grit wet and dry in the sink, nice even strokes across the grain from the last sanding.


Next it the 600 grit, pretty the same as the above but taking care to get a nice smooth surface and remove the scratches from previous stages.


Next, same as above with 1000 grit, if your arms not aching yet you haven’t done enough sanding .


Ahhh the polishing, I would recommend getting a polishing wheel set, they’re quite cheap and save lots of time compared with a polishing cloth and paste. Here I'm using the felt wheel which takes off the sanding marks but creates polishing marks.


Not bad but we can do better can’t we.


The final polishing stage, this gets that final shine that we all know and love. Using the rag wheel and cutting compound (looks like a bar of soap) as below.


This gives you a finish like below.


To finish I put it back on my old card (going to be for a future project).


Any questions comments or suggestions don't hesitate to contact me

 

nice and shinny

 

Thx for the guide
Very "chromy"

 

Thank you, glad someone appreciates it.

 

thanks was wondering just how this was done the other day,
its gonna be usefull for my new mod thanks

 

realy cool just like a mirror

 

Amazing results and a good guide, just what i have been looking for. Thanks a lot!

 

You should probably clearcoat that before too long. One of the features of aluminum is that it forms a very thin layer of light-colored oxidation over its exposed surface, which protects the aluminum from further corrosion. What you took off with the flapwheel might not have been anodizing (if you know for a fact the part was anodized, disregard this) it could just have been the surface oxidation. And whatever it was originally, if you don't clearcoat it it'll be losing its shine soon.

 

Quick questions Jimbo,
1) If i start off with a brushed Alu finish could it turn out like ur final result?
2) Where did u get the polishing kit from? also i would need the rag and whats a good cutting compound? e.g.T-cut?
3) also whats the time duration like? on ur small piece? im thhinking on a much larger scale like case sized scale!

LMk mate.

 

@all

Thanks for the positive feedback.

@crazybob
Anodising is just a very hard thick layer of aluminium oxide on the surface of the metal created artificially by chemicals and electricity.

When polishing aluminium the oxide layer forms instantly, what in effect I've done is made that layer so thin and the metal so smooth that it appears shiny, I probably will clear coat it because over time the oxide layer thickens and the metal appears duller.

@atanum141
Interresting questions which I've given some thought:

1) Yes it would, you would need to make sure that when you’re sanding that the grain from the brushed finish was removed, you could probably start at 600 grit.

2) The polishing kit I got from a good hardware store, mine's a real cheap one (<£10). Yes you would need a rag wheel because the felt wheel leaves marks. The rag wheel doesn't as it is used very lightly. I think T-cut is for car polishing but correct me it I'm wrong, any good metal polishing compound will work even Brasso if left to dry. The polishing compounds I used came with the kit.

3) It took me about 1/2hr sanding and 15mins of polishing, but I wasn't rushing so it could be done faster. If you’re going to polish the side of a case I would recommend an angle grinder attachment Here that uses the flat of the polishing wheel and not the edge, you could cover more area faster and have an even finish.

Thanks

Jimbo

 

Cool, I'll make use of this guide

 

@ D3DAiM

Thanks, glad it's of some use to you.

Jimbo

 

Great guide dude now I really know how to polish aluminum

 

@N.A.N.O.
Thanks

@L2wis
Thanks , glad you think the guide reads well, these guides are the first one I've done and I'm stil learning. Yeah I know what you mean, Its hard to get thet chrome like shine without a polishing wheel.

Cheers,

Jimbo

 

how does a clear coat over polished aluminium come out? the result is far good or you notice the coat?

 

@ Braven
I haven't got around to it yet, not enought time, I'll post when I've done it to let you know.

Jimbo

 

I definitely want to try this on my entire Antec P160 brushed aluminum case...

 

Awww dang, and here was me using HCl solution to do it,

Great work

 

His way probably works better, but using HCL is definately quite cool. Next time cook up and try Fluoridic acid .

 

Christ that sounds lethal *consults the wiki* okay nothing in the wiki, well here i found "a double fluoride, consisting essentially of a solution of boron fluoride, in hydrofluoric acid. It has strong acid properties, and is the type of the borofluorides. Called also borofluoric acid."


Roffle, i don't think my aluminium would ehm exist anymore,