Repainting a carbon frame

Is it a good idea to sand composite tubes?

My fear is that you will scratch the soft epoxy resin to a point where any paint you add on top will look anything but smooth.
I have the feeling that you'll have to use a very fine mesh to give a decent finish before applying the new paint.
Also, if you scratch too hard you might end up exposing the fibre, I guess...

These are just fears, as I've never done anything like that

You shouldn't run into any problems sanding down and respraying the frame, just go nice and slow.

Use wet and dry sandpaper, starting at 320-grit and just key the surface of the entire frame. Going through the paint is not the end of the world, just make sure that if you do go through the paint you go very careful. The resin won't be soft at all and there will be a reasonable layer so it shouldn't be an issue. You will need to make sure that you sand every nook and cranny or the primer won't stick.

If there is any bare aluminium then you will need to used acid etch primer for the paint to stick. Normal primer may stick to start with but will flake off in no time. You will then need to used normal car primer over the frame, and make sure you do at least 2-3 coats so that the whole frame has a good covering. You will then need to flat off the primer with 600 or 800-grit wet and dry sandpaper. This is where you will need to get the surface perfect. Spray on 3-4 coats of base colour, ensuring good coverage and then leave to dry for 30 mins before starting with the lacquer. You will need to do 2-3 coats of this. You can wait 24 hours for the paint to dry before lacquering but it will be harder to get a good finish.

Once it has been lacquered leave to fully dry for 3-4 days before assembling it.

To be honest, it may end up costing more to get a good finish with cans than sending it somewhere like Argos Cycles in Bristol. The paint is going to cost £50-60 plus sandpaper and will take quite a while to do.

If the paintwork is not terrible, you could try some farecla G3 cutting compound to try and bring back the paintwork. Then give it a good wax to add protection.

What colour are you thinking of painting it and whereabouts are you?

moonshine wrote:

Argos resprayed a mates Trek Madone in a 3 color (blacl / red / white ) paint job similar to a Pinarello Prince - it cost him around £500. :shock: We thought he was mad.

Argos do all the Carbon prep by hand, hence why it is so much more expensive than a shotblast that can be done on a metal frame...

If you go to Argos, sit down before you get the quote....!

I just looked on the price list and realised the base price for carbon frames starts at £250! I thought it was less than that, must have only looked at the prices for all metal frames before.

If the carbon is weave type, you could always sand all of the paint off (carefully) and then lacquer the carbon leaving a gloss carbon finish with either raw aluminium lugs or you could paint the lugs. I have done that before and it looks great when finished. If it is unidirectional then it makes it a bit harder to sand down to the carbon, and doesn't look as good when lacquered.. only problem is you won't know until you have sanded the paint!

Out of interest where abouts in the country are you?