Sanding down to raw carbon

[Jacoo]

Ive started with the fork, just wet sanded till the black residue. Feels and sounds different, if i dont sand till the black residue theres still clear coat. Didnt go through the top layer anywhere, seemed easy enough. I will tape off the carbon section and spray the metallic crown a colour close to carbon. Now for the frame, still a bit nervous. Still dont know if i should just sand lightly and then buff to make the clear coat nice again, or all the way through to raw carbon like i actually want to. The fork seemed very doable, but im not sure how different the fork and frame were manufactured. Raleigh fork with leggera frame.

[Goodbadugly]

Any idea on the weight loss of a stripped carbon frame? 

[Jacoo]

Really depends on the frame and how thick the paint was, but apparently anywhere from 100 to 250g, but then most people will recoat (with something lighter) and it will put some weight back. Im not doing it for weight though, just think it will look cool.

[Jacoo]

If i decide to do commit ill weigh the frame before and after

[MrJacques]

Why sand and not use a paint stripper? Would it strip of the clear coat / resin as well?

[Pulse]

If i decide to do commit ill weigh the frame before and after

I like that frame, and think it will look nice when done. It seems there are some areas with fillers around the BB and head tube areas (where its painted black, and you can’t see the carbon pattern). Will you just repaint these areas?

[Pulse]

Why sand and not use a paint stripper? Would it strip of the clear coat / resin as well?

It depends on the resin used, but it will likely degrade the resin.

[ichnusa]

Do it and send pictures of your progress!

[Jacoo]

It depends on the resin used, but it will likely degrade the resin.

Thats right, ive been told to never use paint stripper on carbon. You get a product called carbo lift designed for that, but its very expensive to get in sa

[Jacoo]

Quicker than i expected, took less sanding than the fork. Easy to not sand too deep. Will do remaining decals, then move to higher grit. Im not sure what will happen in the filler (black) areas, but will just see what happens

[Pulse]

The areas with filler has: carbon, filler, clear cote. It looks like your frame has black paintbin the area between the filler and clear.

 

I would just sand progressively until you have a smooth transition from the carbon sections (if that makes sense).

 

As long as you are mindful that there is filler (as you are), and din’t try and ‘find’ carbon, you will be fine.

[Lotus]

Sand it using wet paper....no dust to worry about - also results in a smoother finish.

This ^

 

I've sanded carbon a few times to prepare for respray. You can use an aggressive grit to start,using the existing paint as a guide (change grit when the paint starts disappearing!).

 

The useful thing about wet sanding is that it gives you a smooth finish, you can see when you're getting into the carbon layer (black particles start showing in the water when you "dip"), and as someone else said there's no dust to breathe.

 

Word of warning - be very careful when you sand near any edges where carbon has been exposed by the removal of components, such as around cable posts on the down-tube. Getting a sliver of carbon in your skin is as nasty as a sea anemone spine. You can't get it out with tweezers (breaks off every time you grab it) and it will drive you crazy for days.

[Craai]

This ^

 

I've sanded carbon a few times to prepare for respray. You can use an aggressive grit to start,using the existing paint as a guide (change grit when the paint starts disappearing!).

 

The useful thing about wet sanding is that it gives you a smooth finish, you can see when you're getting into the carbon layer (black particles start showing in the water when you "dip"), and as someone else said there's no dust to breathe.

 

Word of warning - be very careful when you sand near any edges where carbon has been exposed by the removal of components, such as around cable posts on the down-tube. Getting a sliver of carbon in your skin is as nasty as a sea anemone spine. You can't get it out with tweezers (breaks off every time you grab it) and it will drive you crazy for days.

One word: "gloves"

[JM Rides Bikes]

On 3/8/2019 at 10:34 AM, Jacoo said:

If i decide to do commit ill weigh the frame before and after

What was the starting weight? 
 

And were you able to finish it? 
 

Keen to see some pics