[Closed] Rawing aluminium rims.

And the cycle is complete.

I'm pretty sure raw aluminium must have a coating of laquer?

Anodising is done to help harden the outer surface of the alloy, and to help prevent damaging corrosion. Even 'raw' looking components are usually anodised. On something as thin-walled as a rim, I'd be extremely wary about removing an anodised surface. And this is from someone who'd sand the lacquer off some carbon handlebars. 😯

Anodising can be removed from components, using a solution of Sodium Hydroxide (caustic soda). Nasty stuff, so you'll need to protect your skin and especially your eyes. You will then need to neutralise the alkali with acid (even vinegar is good for this). The raw alloy will then need polishing up to provide a smooth surface (corrosion and oxidisation is slower on a smooth surface), which will need to be kept clean and polished, as there's now no anodising to protect it. I'd say it's ok on thick-walled/dense components like cranks, CNCed stuff, but on a rim?

Buy a silver one and save yourself the heartache.

if you try and lacquer raw aluminium with DIY sprays I can pretty much guarantee that it will flake and look terrible after a while as moisture gets inside and oxidises the aluminium.

use some proper aluminium polish that will leave a protective coating and keep on top of it if you want a shine.

For stripping lots of very fine wet and dry and water as lubricant. You could use a buffing pad and some cutting compound on a dremel around spoke nipples if not dismantling. Look up the crank polishing threads.

^ i'd not considered the thickness of a rim. Mechanical removal of the annodised finish will have a degree of risk I guess due to the depth you will have to go.

Now, my chemistry is a little hazy, but surely aluminium oxide would be stronger than any lacquer.

depends on the damage case bt we won't go into that and just say yes, a properly built up layer of aluminium oxide (ie the annodising) is generally the best route and the best adhered as aluminium is a PITA to bond to without etch primers or other treatments

Some of the heavy duty water soluble degreasers are caustic enough to remove anodizing from aluminum! Just wear gloves.

Don't ask how I found this out. 😳

At a tangent - if you do want to paint anodized aluminium then get it hot water sealed.

Big thread on weight weenies about this.

Some people saved 15g!! 😉

Aluminium oxide may protect somewhat but won't it look ugly? Like a white crusty mess?

JRA have a pair of polished 26" Flow rims in their sale section.

Maybe worth finding out if they did the work and how it was done?

Just had a pair of Surly Marge lite fatbike rims stripped and re-anodised in Silver. Look really good. Not super shiney more of a satin effect because of the original shot peaned finish.

[b]bartyp[/b] - [u]Member[/u]

Anodising is done to help harden the outer surface of the alloy, and to help prevent damaging corrosion. Even 'raw' looking components are usually anodised. On something as thin-walled as a rim, I'd be extremely wary about removing an anodised surface.

Surely anodising wears off the braking surface on rim braked bikes, or am I missing something?

Do you already own the rims? If not I think stans do or used to do them in painted white. This would be easier to strip than anodising. I looked at doing similar but getting them powder coated fluorescent yellow. Couldn't get anyone to powder coat the yellow though so I gave up. I haven't read all of the currently running thread about clear powder coating a frame but that could be an option after they have been stripped. Or maybe clear anodising. I have a raw giant trance that I believe is clear anodised and it still looks as good today as the day I bought it in 2008. Scratches don't show up because they are self coloured. The anodiser I have used at work will strip parts so even if you can only get anodised rims it will still be do able. I did some experiments home stripping parts with caustic soda. Results were very good and the underlying finish was very good. But as above it is nasty stuff so take note of all the warnings on the bottle.
I say go for it.

Surely anodising wears off the braking surface on rim braked bikes, or am I missing something?

Braking surface will probably be on a thicker bit of metal. The braking action will help polish the surface, and remove corrosion. It's designed to do that.

This cross section of a rim will help illustrate this further:

[img] [/img]

Would you want to remove any material from anywhere else on that rim?

I know 18 bikes did this to a set of flows which look lovely. Give Si a call and I'm sure he will tell you about it

I've removed anodising from loads of stuff having gone theough a silver parts only phase some years ago. As above, it's easily enough done with some caustic soda and some care. I wouldn't be concerned about loss of strength as most colour anodising is very thin and far from structural. What you would need to be wary of is caustic staying too long inside the rim cavity - just do a small section then rinse thoroughly and repeat.

All that said, I currently have some polished Velocity Duallies on one bike and they look great when alll clean amd shiny but are a bitch to look after....

JRA do paint/ano removal and polishing, only as part of a wheel build. I get the impression that it's too much of a faff to offer for rim-only purchases.

Just checked the JRA website and they're doing polished 26" Flows for £19.99. Got to be wrong surely or is 26" that much of a dinosaur!

[url= http://www.justridingalong.com/stans-notubes-ztr-flow-polished.html ]JRA Flows[/url]

Blimey. That's well into "I have no use for these whatsoever, but at that price..." territory.

Looks like price for the pair too. [s]178.99[/s] > 19.99

troberts - you'd want to unlace your rim before you started stripiing the anodising, so just get those ^ instead, save yourself a few hours' elbow grease and chemical exposure.

I have a set of high polish H+ Son Rims on my road bike - they started to look a bit tatty after one winter's riding, so I really wouldn't put them on an mtb.

are they starting to look a bit... raw?

I have used caustic soda since the 80s. Anyone old enough to remember the early days on BMX will know that if it was going on a BMX then it was anodized (blue, gold, red etc,.) but rarely did the same colours match across different brands. Answer - take it all back to silver.

Easy enough to do with small components as just put the whole thing in bucket but a rim could be tricky unless you have a massive receptacle?

Be careful with amounts as it can easily bubble over once it gets going and the reaction is also exothermic (respect that chemistry)

I thought I was alone in the world for wanting polished silver rims, I will be doing something to a pair soon.
Reading all of this with interest.

Cheers Kit 🙂

Thanks for all the feedback, even if there are a number of conflicting views! I'm not keen on the idea of using caustic soda so I've decided to use elbow grease and some super fine wet and dry. The rawing has officially begun so there's no going back. Spent a couple of hours last night in front of the tv and I've done about a quarter of the rim so far, what a bloody tedious job! The section I've rawed does look good though, I'll crack on today and hopefully the finished product looks neat and shiny! I'll get some pictures up when I'm finished.

The section I've rawed does look good though, I'll crack on today and hopefully the finished product looks neat and shiny! I'll get some pictures up when I'm finished.

You'll need to be fastidious with keeping it waxed/ polished, or the finish will dull very quickly.

You'll need too keep them very clean and away from road salt otherwise they are likely to be at risk of stress corrosion cracking.

I've had a rear road wheel fail like this, cracks running out from the nipples on all the drive side spokes.

I'm not too bothered about the finish, I just like the industrial bare metal look. Regarding corrosion I'm not too worried, I'm extremely anal when it comes to washing my bike and it's kept in a warm dry hallway so it'll be reet. If it does corrode and explode then I'll buy another rim and not mess with it!

I'm not too bothered about the finish, I just like the industrial bare metal look.

Hmm. I stripped a black seatpost with caustic soda, and polished it up with metal polish. When the finish dulls, it just looks dirty rather than industrial.

Spent a couple of hours last night in front of the tv and I've done about a quarter of the rim so far, what a bloody tedious job!

That is why we use caustic soda, literally 1 minute job (although the polishing afterwards takes some time.

Many hours of wet and dry later I now have a lovely raw rim. 😯 Gave it a bit of a buff with Autosol and it's looking damn shiny. I'll get it built up tomorrow and my pimping trail wheel will be underway.

Image links aren't playing ball so pics are here if anyone is interested. https://www.flickr.com/photos/137161098@N02/albums/72157660827751409/with/22828663837/

Drain cleaner strips anno very nicely. few mins. Oh, you've taken the sandpaper to it - carry on 🙂

Honzo is looking pretty decent with a nicely polished rear rim.
https://www.flickr.com/photos/137161098@N02/albums/72157661777854322