Think mum bike would look better with silver cranks. Nice new cranks, chainring plus BB would set me back the best part of £400. My SLX cranks are scratched, suffering from heel rub and mechanically sound.
Thinking of removing the anodising using caustic soda (sodium hydroxide). Anyone tried this before with success? Other than potentially losing my sight and ending up in A&E is there anything I need to be aware of?
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I did mine with cheap oven cleaner and polished them with Autosol. Couldn't be easier.
Yeah i did some pedals with oven pride recently - dead easy only took about 20 mins
Oven Pride?
Sounds safer than dicking about with acid.
What's the process?
Not fussed about polishing as they'll get scuffed up soon enough.
What's the process?
Just use a toothbrush (probably not the one you use as a daily brusher!) and scrub using oven pride. Keep applying more / scrubbing more until the anodising is off
You kind of need to polish them. The raw finish is a dull grey with a rough surface. I used a polishing mop in a drill to buff them up.
They don't stay bright and shiny but they look a lot better than when they're freshly stripped.
Don't be shy with the oven cleaner, it's not very aggressive. Just soak them and leave them for ages. Checking them and brushing them every 5 minutes is just more work.
A few years back now, it was Mr muscle oven cleaner. Leaves them a rough grey colour that comes off easily with brillo. Quick going over with autosol/silvo works a treat.
Mostly used on stuff that was polished and anodised, so came up mirror, anything more satin and anodised may require something more gritty to polish, but if you're just after clean silver look then oven cleaner and Brillo will do the job.
From memory the oven cleaner removes any dye or colouring applied during the anodising, if the material was smooth polished before anodising it’ll be smooth after stripping, likewise if it had a slightly textured finish pre- anodising it’ll remain coarse afterwards.
Either way the aluminium might be a little patchy in colour once stripped so I’ll be worthwhile at least giving them a quick once over if not a full polish.
I just used caustic soda in a plastic bucket. Wear gloves and eye protection. As above it'll need a lot of polishing if you want it to come up shiny.
Oven Pride?
Sounds safer than dicking about with acid.
Oven cleaners are sodium hydroxide, just mixed with thickeners and expensive packaging.
Anodising modifies the surface layer of the aluminium to make it a honeycomb, and the dye can get trapped in the cells. All you're doing is stripping off that outer layer. Doesn't matter if you do it with chemicals or with a stripping pad.
If you do use caustic, be wary that it is eating the aluminium, be aware that if you leave it long enough (and with enough caustic) the cranks will dissolve completely, and there's always the risk it might interfere with things like the the press fit on the axle or the threads. Rinse the parts in dilute acid like white vinegar to make sure any traces are removed afterwards.
I did mine with cheap oven cleaner and polished them with Autosol. Couldn't be easier.
Right... The cranks have been soaking in a mass of foam provided by Mr Muscle for the best part of two hours.
They're a bluey colour and even when rubbing down with a Scotch-Brite pad there's still a fair amount of anodising left.
How was it supposedly so easy?
Mr Muscle isn't that strong, or useful for stripping anodising. Oven Pride is the best stuff, BMXers swear by it.
Aha....
Have some cheapo generic oven cleaner. Will give it a coating with that, too.
I think mine was called Elbow Grease and it was dirt cheap in B&M.
Nice and tidy now....they just don't really match the frame now- just a shade or 3 off. Maybe as they oxide they will look closer to the frame colour.
Given a choice, black to match the rocker would have been my choice.
If we are obsessing about colour combinations are we ignoring the elephant in the room...the orange pedals and yellow coil?
I cant bring myself to run yellow grips (which would have to match the yellow pedals) as I think they look naff. I was torn when choosing between the Öhlins and Fox DHX2, but was swung by the reports of the DHX2 suffering from some squelchy oil issues. The orange grips and pedals are the same ral as what Fox use on their Factory stuff... Thought that the pedals and grips would at least match the forks, but they've seemingly gone gold and ditched the orange.🫤
The cranks were previously black, but the anodising had worn through which, again, looks naff.
I've got plenty of oven cleaner left over. Could always do the rocker 🤪 to match the cranks.