I have a plastic water bottle that I dropped. It now has a dent in the base, and is somewhat unsteady when standing up. How can I repair this dent without causing cracks in the plastic that will cause it to leak?


Fill it with sand, salt, sugar, or some other granulated material. Use a dowel to pack it down. With enough pressure in the correct area, the dent will pop out.

  • Wouldn't that be a total waste of sugar/salt tho? – Just Do It Feb 23 '16 at 15:30
  • Dry salt and sugar will pour out easily. – Adam Zuckerman Feb 23 '16 at 15:33
  • Fair enough, let's just hope it doesn't get messy(use a funnel) – Just Do It Feb 23 '16 at 15:36
  • just have to make sure the bottle is dry as well – Dragonrage Feb 27 '16 at 0:16

I don't know how tall the water bottle is but you can easily push the dent out using the handle of a wooden spoon, it's thin enough to fit through the mouth of the bottle yet stiff enough to apply good pressure.

wooden spoonTry it..!!

  • Downvoter: I would like to know why this answer is not useful, that way I can improve it or just delete it all-together – Just Do It Feb 23 '16 at 15:29

I found that just blowing compressed air into the bottle will expand the area you want to its original shape.

  • I am just curious, how does one blow compressed air into the bottle, to create enough pressure to repair the dent? – virolino Jul 17 '19 at 11:52

Put the empty bottle with lid on in the freezer. After a few hours, take the bottle out and put it in the hot sun. The pressure of the expanding air hopefully will pop the dent out.


If your saying the bottle is extruding on the bottom (or pushed out) Simply get hot steam in the bottle and use an object to push the base inward.


Fill it with water and swing it around with the cap off (possibly on a rope). Centrifugal force will push the bottom outward and fix the dent.

  • 1
    what difference does having the cap off make? – Dragonrage Feb 23 '16 at 1:13
  • 1
    Air can come in freely as the bottle expands. – k-l Feb 23 '16 at 1:33

Simply push the dent with something hard.


If its made of metal, fill it with water and put it in the freezer. if the bottom expands out when you do this, tap it with a hammer.

  • That's a great answer... But the question is specifically about plastic. – L.B. Mar 28 '17 at 13:25
  • Wouldn't plastic expand easier than metal? – Heath Wright Mar 29 '17 at 4:53
  • Yes, but it may split or crack depending on the material – L.B. Mar 29 '17 at 14:20

Cold water with ice inside.. pour boiling hot water on the dent outside

  • 3
    I kind of fail to understand the physics involved - could you please elaborate how and why this should work? – Stephie Jun 10 '19 at 21:44
  • @Stephie Pouring hot water on the dent (and only the dent) causes that part of the metal to expand and correct the dent. Search youtube. O.P. asks about a plastic water bottle though, so this may not work. – SurpriseDog Jul 18 '19 at 3:19
  • This is the length of a comment but seems to try to answer the question. It needs beefing up at least, re-writing more likely. – Willeke Sep 14 '19 at 16:35

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