In anticipation of a bout of long, hot, cycling, I cleverly popped two of my stainless steel water bottles into the freezer the night before.
Naturally, I filled them only part way — about three-quarters full. They were frosty-wonderful when I popped them into Basil’s new bottle cages.
Imagine my surprise, then, when I stopped to swap bottles, and discovered only a chunk of ice at the bottom of one bottle.
The frozen water had stressed the stainless bottle beyond endurance, causing an explosion. This was painful to see. Also, this result rendered my “frozen bottle” approach considerably less clever than I had originally thought.
Had I filled a plastic container with apricot preserves, and left only a half inch at the top, all would have been well. Obviously, my calculations for actual ice were off; Mr. Diarist suggests, additionally, that the narrowing of the Sigg bottle toward the top may have played a part, depending on how the freezing actually progressed.
The second bottle escaped with stress marks (stretch marks?) along the side. Also, the bottom is now slightly convex, which causes it to rock a bit when set on a flat surface.
In future, I’ll fill the replacement bottle, and the other two, only half way up the lower portion of the bottle. Just before leaving, I’ll add cold water to top up. This won’t keep my libations as refreshing as would solid ice melting, but will keep down the water bottle replacement expenses.
2 replies on “Ice: Stronger Than Steel”
Actually you can safely much more than half fill a bottle with water before freezing it by tilting it in the freezer so that an air space runs from the top to the bottom of the bottle. I usually fill and tilt bottles so the air space runs from the top of the rim of the base to the bottom of the rim of the top opening which is quite full, but if the top is water tight you can increase the tilt … provided an air space reaches from at least part way across the opening and right to the bottom of the container. Obviously you still have to leave sufficient space for expansion but it’s not as easy to overdo the fill, and problems such as you had with the necked in area or the top freezing first and forming a plug are usually avoided. Just before use you fill the air space with cold water … or chilled water if you wish. For reasonable sized bottles this system easily lasts most of the day in the hot Australian sun. The tilt also allows a much greater surface area of ice to be in contact with the water. Obviously you can judge the quantity of water to be frozen more easily using transparent plastic water bottles rather than metal ones, and they might be a cheaper way to experiment before risking another metal one.
Ian M, I love these tips — good point about the plastic water bottles, too. (I suppose I really should ride with them, since they’re lighter, but I do like the metal so much better.) At any rate, some experimentation is in order; the more ice the better, but not if I’m exploding my water bottles. Tipping the bottles is brilliant; I’ll give it a try.