MegaSack DRAW - This year's winner is user - rgwb
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Not loving the goldfinger effect of my Renthal duo stem I'm thinking about removing the ano from the bottom section. I know the ano is there partly to protect the Aluminium so I'm wondering - will it effect the strength of the stem? I've de-anodised a few bits and bobs over the years so know how to do it (using caustic soda) but never done it on a part that - well I'd rather not see break...
Pretty common to 'raw' a stem in the BMX community but those stems are like a house brick and get changed every year for the next stem from fit or cult or whoever the kids follow that year so not a great indicator.
Does anyone have an informed opinion on this? Easiest answer is not to do it, and stop being a tart which is what I'll still be defaulting to unless someone makes a good argument for it not making any difference beyond it might go a bit dull after a while.
If it were me I'd set about polishing it off. Takes a while but at least it's not anywhere near as corrosive as caustic soda. To be honest I'd probably do neither to a stem. Bit too critical. They're your teeth though.
Use the inside of a shoe - that will take anything off
Permanent Black Marker?
Use an angle grinder [i]very[/i] lightly. Should* be fine.
Based on nothing but end-user experience, polish it off. I'd have guessed it wont make any difference to the strength but, well...
*may or may not be true
Polishing it off is going to remove more material than chemically stripping. If you keep an eye on it you'll remove 25um to strip the anodic film with caustic. I'm pretty sure an angle grinder will be alot more. But you would need to polish it after anyhow to get a decent finish, Green Scothbright pad is what we use.
Think I'd have to use caustic - too many fiddly bits to polish easily. I've done it loads of time before though should be okay. What I'm worried about, or don't know about is will the bare aluminium be prone to fatiguing / cracking? One option would be to clear lacquer it afterwards?
Shouldn't have an affect. If it's merely decorative the anodic film will be 25um, so it's not like your removing to much of the substrate. I would lacquer it though, or it will look a bit poo very shortly.
any particular type of lacquer? Think I've got a plasticote clear lacquer I used for a set of cranks once - would that do?
Just buy a new stem and think of the many hours you've saved yourself so you can go out riding....
Don't really see the point as you can't see the gold bit while riding but to save your self hours of fannying around…
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Failing that get some Renthal bars and embrace the goldness
If you want to remove it easily and properly.
get yourself some of this http://gaterosplating.co.uk/Anodise-Stripper-and-Etch.php
That's what I use for my Ano prep and ano removal.
Works a treat and is effortless..
I wouldn't be using caustic soda on a critical part, it reacts with both aluminium and human tissue and eventually dissolves both. I don't have your experience though
Long ago, I bought a pair of Turbine cranks from Race Face. They were anodised. Rafce Face's manual said "If you do not like the colour, sell them and buy some different cranks, but for chrissakes don't be removing the anodising" (words to that effect).
I doubt that is the last word on the science of removing anodising, but it has stuck with me rather.
đŸ™‚
I'm no chemist, but I can see a world of hurt coming your way if you get microdamage to the structure of the stem from the CS.
If there's any pores in the metal you might get bigger holes "behind" them you can't see, and if the soda spreads along an impurity/crystal boundry you might also get a "crack" formed in the metal meading to stress concentration and death*.
Pedals, top caps etc, yes. Stem, no thanks. Too much "riding over your own face" potential.
*Exact quantity of death not guaranteed.
I've had a word with myself and have abandoned this for now - although not 100% convinced of death as the outcome I'm sufficiently convinced there is some doubt.
Where about's are you? Anywhere near the South East?
[i]Where about's are you? Anywhere near the South East? [/i]
North West, so nope đŸ™‚
When parts are originally anodised they are etched, in fact i would bet that most bike parts are chemically brightened as well in order to get a good shiny finish. Both of these processes remove the substrate, but you are talking microns, not mm's. Ah well, have a look on Google, there will be a little one man band platers somewhere near you who could strip it in min's for a few quid if you are that bothered.