Patching aluminium frame corrosion

[Mr Celine]

This is what the road salt of 15 Scottish winters does to the chainstays of an aluminium frame.

My preferred method of resolving this problem would be n+1 but due to ongoing supply issues this doesn't seem to be an option at present, so I need to get at least one more winter out of it.
I intend rubbing down the bubbled and flaking paint before repainting. It doesn't need to be a good match or even look pretty.

Does aluminium need a special primer? I have some ordinary grey metal primer and some fancy zinc version. IIRC Al is higher in the activity series than Zn so the zinc primer would make things worse.
Does hammerite stick to aluminium without a primer? If not, what sort does it need?

 

[I like Skol]

Get it bead blasted and powder coated? Should come out good as new.

 

[si_c]

Get it bead blasted and powder coated? Should come out good as new.

Exactly what I was about to suggest. You'll lose the branding on the bike but you'll actually end up with a finish that will probably be harder wearing than the original. Plus you'll get a good idea of the state of the underlying metal. Last time I enquired about getting it done it was ITRO £70 for a frame and forks, but you'd best check about aluminium you can't do carbon forks though.

 

[I like Skol]

Exactly what I was about to suggest. You'll lose the branding on the bike but you'll actually end up with a finish that will probably be harder wearing than the original. Plus you'll get a good idea of the state of the underlying metal. Last time I enquired about getting it done it was ITRO £70 for a frame and forks, but you'd best check about aluminium you can't do carbon forks though.

It needs to be the right kind of blasting so it doesn't blow holes in the aluminium while still being powerful enough to clear the oxide. Speak to the company and check they know what they are doing so they don't reduce an otherwise good frame to scrap!

 

[midlife]

Iirc aluminium has a specific acidic primer if you don't want to go the refinish route.

 

[Drago]

Soft media blast, nylon powder coat, sit back and admire.

 

[Mr Celine]

I don't think it's worth spending much more than £70 on it and I'd assumed it would be considerably more than that to get it blasted and powder coated.
Can anyone recommend anyone that does powder coating in southern or central Scotland?

 

[Drago]

Ive never paid more than a bullseye for a blast and coat, and ive always had decent results.

 

[overmind]

Personally, I would just lightly sand the bubbly bit (and lost paint bit) with some emery cloth and then just paint over it - I went to Halfords and found some touch up paint which more-or-less resembled the existing colour when I had a similar problem - and then used that to paint over the sanded bits.

That would probably be good enough for at least another 10 Scottish winters.

 

[fossyant]

Look for a local alloy wheel repair centre. They often do frames. Its less than £50 locally for me

 

[cyberknight]

had my old boardman blasted and repsrayed for £50 during lockdown at a local auto sprayers , only catch was i had a choice of whatever colour they were working on that week.
it had bubbled badly at the bottle mounts plus covered in chips

and it was a devils own job to home strip
1st piccie is where i gave up after numerous attempts to strip and second is the finished job

 

[ianrauk]

Good job that. The yellow looks great.

 

[overmind]

Did they put the Boardman transfers on too?
(agreed, that looks really nice. :-) )
(charge spoon saddle too. I have one of those)

 

[cyberknight]

Did they put the Boardman transfers on too?
(agreed, that looks really nice. :-) )
(charge spoon saddle too. I have one of those)

I bought the transfers from ebay , the spoon saddle or fabric scoop is on all my bikes as about 2 years ago i found my ass couldnt get on with the flat narrow saddle design.Since that photo my saddle height has also dropped 5 mm as i get older aka shorter .
I am half tempted to try a flat saddle again to see if the saddle drop has made a difference as i was gettign saddle sores on the edge of the saddle i reckon from being to high

 

[Chislenko]

I think you were extremely lucky that was the colour of car they were painting that week.

Looks very nice.