First post. Hi everyone. I was watching this video on how they make bike frames: https://www.youtube.com/watch?v=LJ46J3NQIVg
They say they wrap the carbon around a “removable” core. I see them putting the carbon on, putting it in a mold, curing it, and then… well how do they get the core how to get a hollow frame?
like you said, they remove the mandrel…
looked like in one shot it was a bladder. Though the mandrels looked pretty solid. They might be some form of thermoplastic material that is poured into a mold and then cooled to be used for layup? And then when it’s heated it would melt out. Of course they’re not gonna show the good stuff on their video.
there’s also the how stuff’s made video on CF bikes that shows the techs laying up on a rubber mandrel. I’d imagine it’s something like that.