vessel : Carbon Fibre Water Bottle
IPD501 Project at UPenn
Spring 2014
For IPD501: Integrated CAM/CAD/CAE, we worked in pairs to "make a vessel" via composite layup. My partner and I were inspired by Koenigsegg's method for making turbo pipes, so we decided to try it for ourselves and make a carbon fiber water bottle.
We used epoxy-sealed MDF for the two-part clamshell mold. We designed the mold to be as easy to connect and to release as possible: six stainless steel alignment pins connect the two halves and the outer part of the mating faces of the mold is recessed to leave room for a pry-tool. I made an inflatable bladder to go inside the mold and an aluminum top plate with a quick-connect valve to hold the bladder in while under pressure (~30psi).
CLAMSHELL MOLD
CURED LAYUP IN MOLD
REMOVED FROM MOLD
We had better luck with wet layup than prepreg, since the two halves had to be laid up separately and then combined and the wet layup was less prone to sticking everywhere. Since a light and durable water bottle is perfect for outdoor recreation, we decided to make our bottle interface with standard Nalgene lids. We used a custom-ground threading tool in the CNC lathe to machine the aluminum bottle top and added a slot to attach a strap.
MACHINING LID INTERFACE
READY FOR POST OPS ON MILL
MOUNTED TO BOTTLE
COMPLETED BOTTLE
This project was my introduction to carbon fiber layup and custom turning-tool design. While our bottle turned out beautifully, it was heavier than we had anticipated (due to our generous wet layup) and we forgot to use food-safe epoxy, so it became an ornament in the engineering school display case.