Project CSG

Yeah.

Anyway, updates:

Forks in all their bare UD glory - 294g

FD clamp - 6g

That clamp is the lightest on the market and costs pennies compared to Parlees.

The urea in the bukkake finish. Might not play well with the epoxy binder. Neither will the residual protein polish very well.

Bins cadbury's cream egg

That clamp looks familiar

So you've cling-filmed it, then?

Really? I'm far from being an expert at carbon repairs but I thought you had to remove the majority of the material from the cracked area and then build up the layers to the required surface level. Patching it up as it appears you have done does nothing to stop the crack from propagating.

How do you remove the material from a hair-line crack when the tube is 1mm thick?

I think the carbon layers effectively form a new tube over the existing tube bonded to the good parts therefore strengthening the whole??? That's my logic anyway.

Also what you didn't see there was the second layer of UD carbon under the peel cloth. This process will is repeated twice more with a sand back in between.

BTW I'm well up for some advice if there are any budding carbon experts out there!

Finally found the thread I was thinking of. There's a lot of helpful information in here.

http://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=65681

I would wrap as much of the tube as you can dude.... how much matting did they give you?

Loads.

So... Some interesting things happened.

Plus points

• The repair is very, very solid.
  
• The UD layer looks great cosmetically
  
  
  

Minus points

• The tube has a bulge in it where the repair is, sits proud about 0.5mm
  
• The shrink wrap tape overly-compressed the tube deforming the shape of the top-tube where the crack had been
  
• The deformation will need to be filled and the process repeated
  
  
  

Interesting points

• The squeezed out epoxy mix hardens on the tube and is a nightmare to get off so should be wiped down whilst still dry
  
• Carbon is pretty easy to work with
  
  
  

Next steps are sanding back the repair, filling the deformation with a 2-part filler, allowing to cure and then applying a further 2 layers of carbon weave repair.

I will make thenext layer cover the crack plus 20mm and the last layer extend hugely over the crack by 100mm either side and wrap the entire tube.

Should be ok.

Straight out the wrap

Sanded back

Filler applied

Good progress, Señor.

Nice.

Really looking forward to seeing how this turns out.

Filled deformity, sanded back to flush now ready for carbon layers 2-5

nicely done with the repair! I have a question regarding carbon repairs (not that i have any carbon to repair). If you repair a tube, as you have done, the repair area will be significantly stronger than the original area and therefore the stresses on the tube will no longer be evenly distributed along the tube but concentrated to the areas either side of the repair. Is that the case? and if so does it worry you?

by the way, i like the look of all your other carbon goodness.

Yes, it worries me. I'll be especially worried whilst descending Alps in July.

How hard did you hit it when you broke the top tube?

Not hard at all.

Are you concerned that the light impact didn't start the crack, but finished it, if you see what I mean? i.e. the tube started to crack after hitting a pot hole or similar, then when you knocked it over you finished the job?

Yes I'd be worried too. However in my experience after worrying about a repair of some sort for about too weeks the anxiety dissipates and you feel better. Unfortunately the potential danger is still there.

Are you concerned that the light impact didn't start the crack, but finished it, if you see what I mean? i.e. the tube started to crack after hitting a pot hole or similar, then when you knocked it over you finished the job?

This was what Is aid to Bianchi when it went back to Italy. They dismissed this and replied with "we have examined the frame and it appears to have been hit with a blunt object (like a hammer)"

It defo broke far too easily, but hey, lets see what happens when it's rolling again.

If it goes tits up I'll just buy another frame

Another day, another stage. This time, layers 3-5, bottom layer is 45/45 twill then 2 layers of UD, fibers running length of tube. Layer 5 is a vanity layer and some will be sanded back to create some smoothness to the finish. Just gotta wait 24 hours now. crosses fingers