June 5
June 5, 2005
A carbon fiber Hammer Gel flask holder
Here’s a step by step how-to for something a bit different that I’ve been meaning to build for quite some time now – a carbon fiber Hammer Gel flask holder. On my triathlon bike I have been using a fabric and Velcro “Bento box” that straps onto the top tube just behind the headset. It fits 4 Hammer Gel flask quite nicely, but because it’s made of fabric, when I hit a bump, one or more gel flasks go flying. This has happened during a race before – in fact a few times and once I even lost an entire flask during an Ironman – not acceptable.
So, I decided to make a molded carbon fiber flask holder to hold 4 Hammer Gel flasks. I’ll put hammer gel in three of them (about 5.5 hours worth of calories during a race or long ride), and salt tabs in the fourth flask. Here’s how I made it:
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1. I wrapped duct tape around the stand for my wind trainer which happened to be the same diameter as my top tube on my triathlon bike. Epoxy resin doesn’t adhere to duct tape. Then I cut a couple of Styrofoam blocks to hold 4 gel flasks in the correct position. |
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2. A light spray of contact cement on the carbon fiber fabric will adhere it to the mold so it doesn’t peel off once the epoxy resin is added. |
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3. I wrapped a couple of layers of carbon fiber fabric around the flasks, and then around the tube at the bottom. |
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4. The whole thing is wetted out with epoxy resin. |
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5. After the epoxy cured, I cut the tops off with a Dremel and cutting wheel. |
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6. The plastic gel flasks were pulled out and the whole thing was sanded smooth. |
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7. To remove it from the frame, and to attach it to my bike, I cut a 1/4″ slot on the underside. |
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8. A fresh coat of epoxy resin puts the gloss and the pop back into the carbon. I cut a slot through the bottom and added a Velcro strap to secure it in place.The flask holder works perfectly – the flasks fit very snug, but are still easy to pull out.
Unfortunately, this is mostly about function and not a whole lot about form, as the flask holder looks sort of like it congealed on the top tube rather than a commercial product. It’s a big wobbly and wrinkly and one of the flasks wasn’t completely square with the others – but hey – not bad for a carbon part made without any molds. |
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Xavier on May 4, 2021
Well done! I was about to start making a carbon flask holder, and I decided to search the net. You did a great job.