# Cutting the bottom off of a plastic 5 gallon water bottle **URL:** \ **Category:** Factual Questions\ **Created:** [March 1, 2010, 9:25pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919 "2010-03-01T21:25:10Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![Mangosteen](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@Mangosteen](https://boards.straightdope.com/u/Mangosteen)\ **Post date:** [March 1, 2010, 9:25pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/1 "2010-03-01T21:25:10Z")
What would be the best way to cut off the bottom of a 5 gallon water bottle? I know a hack saw would work, but I have to cut 26 of them. Would any of the Dremel tools work? Thanks! ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [March 1, 2010, 9:28pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/2 "2010-03-01T21:28:35Z")
Heat a big knife(or machete) and melt your way through. ---
**Author:** ![imfloating](https://avatars.discourse-cdn.com/v4/letter/i/bc79bd/32.png) [@imfloating](https://boards.straightdope.com/u/imfloating)\ **Post date:** [March 1, 2010, 9:34pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/3 "2010-03-01T21:34:01Z")
> [@Mangosteen](#): > > What would be the best way to cut off the bottom of a 5 gallon water bottle? > > I know a hack saw would work, but I have to cut 26 of them. > > Would any of the Dremel tools work? > > Thanks! Why? ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 1, 2010, 9:36pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/4 "2010-03-01T21:36:25Z")
How rigid is the plastic? if it’s fairly sturdy, a jigsaw (scrollsaw) might be suitable, followed by a rasp or file to clean up any frayed edges. Are you making cloches, by any chance? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [March 1, 2010, 9:48pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/5 "2010-03-01T21:48:28Z")
I’d use a [wire saw](http://www.amazon.com/Stainless-Steel-Commando-Wire-Saw/dp/B000E96CZ4). Make a jig to guide the saw and hold the bottle steady. ---
**Author:** ![Hampshire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hampshire/32/4887_2.png) [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Post date:** [March 1, 2010, 9:50pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/6 "2010-03-01T21:50:46Z")
I’d use 2 people and go with the jigsaw. One to hold the bottle secure and the other two use 2 hands on the jigsaw. ---
**Author:** ![UncleRojelio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/unclerojelio/32/3160_2.png) [@UncleRojelio](https://boards.straightdope.com/u/UncleRojelio)\ **Post date:** [March 1, 2010, 9:55pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/7 "2010-03-01T21:55:40Z")
A hot wire would prolly work. ---
**Author:** ![Mangosteen](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@Mangosteen](https://boards.straightdope.com/u/Mangosteen)\ **Post date:** [March 1, 2010, 9:55pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/8 "2010-03-01T21:55:44Z")
> [@imfloating](#): > > Why? Mini greenhouses. I’m getting several young palm trees delivered from Reunion and they are arriving completely bare root. The fronds dry out rapidly and the plants die if they are not grown at least initially in very humid conditions. The palms will be planted in pots and placed on bricks that are in large dishes filled with water. The bottom-less bottles are placed over the palms and on top of the bricks. The water is not quite to the level of the bricks so the pots won’t be absorbing water from the dishes. The palms are watered by hand. As soon as the palm _catch_ that is start growing again on their own, they can be removed from these mini greenhouses. ---
**Author:** ![Mangosteen](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@Mangosteen](https://boards.straightdope.com/u/Mangosteen)\ **Post date:** [March 1, 2010, 9:57pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/9 "2010-03-01T21:57:53Z")
> [@Mangetout](#): > > How rigid is the plastic? if it’s fairly sturdy, a jigsaw (scrollsaw) might be suitable, followed by a rasp or file to clean up any frayed edges. > > Are you making cloches, by any chance? Yes. Sort of. See below. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [March 1, 2010, 10:21pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/10 "2010-03-01T22:21:30Z")
Do you have access to a band saw? That would probably be the easiest way. Otherwise two people and an angle grinder would probably do it with considerably less vibration then anything that reciprocates. Hell, one person could to it if you mounted the angle grinder into a vice or clamped it to something. ---
**Author:** ![Cowgirl\_Jules](https://avatars.discourse-cdn.com/v4/letter/c/4af34b/32.png) [@Cowgirl\_Jules](https://boards.straightdope.com/u/Cowgirl_Jules)\ **Post date:** [March 1, 2010, 10:28pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/11 "2010-03-01T22:28:54Z")
A sawz-all probably wouldn’t take too long either. Drill a decently sized hole to get it started. ---
**Author:** ![Snowboarder\_Bo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowboarder_bo/32/229_2.png) [@Snowboarder\_Bo](https://boards.straightdope.com/u/Snowboarder_Bo)\ **Post date:** [March 1, 2010, 10:40pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/12 "2010-03-01T22:40:07Z")
If you use a saw, you are going to be there a long time, and none of your cuts is likely to be uniform to any other. Hot wire cutters are easy to make. > **[Hot Wire Foam Cutter](https://www.instructables.com/Hot-wire-foam-cutter/)** > > Hot Wire Foam Cutter: Cheap ($30+-) and easy to build hot wire foam cutter made from commonly available parts. Cuts styrofoam for surfboards, model plane wings, sculpture, model train or tabletop wargame terrain, 3D sign letters, mold models for lost... I completely agree with **beowulff** about the jig. And once you make the cutter and the jig, don’t throw them away or dismantle them. That kind of thing comes in handy sometimes. ---
**Author:** ![Saltire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saltire/32/553_2.png) [@Saltire](https://boards.straightdope.com/u/Saltire)\ **Post date:** [March 1, 2010, 10:43pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/13 "2010-03-01T22:43:06Z")
If you do go with a hot wire or knife, be sure to ventilate well. The fumes off the burning plastic could be hazardous. ---
**Author:** ![BrotherCadfael](https://avatars.discourse-cdn.com/v4/letter/b/977dab/32.png) [@BrotherCadfael](https://boards.straightdope.com/u/BrotherCadfael)\ **Post date:** [March 2, 2010, 12:22am UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/14 "2010-03-02T00:22:25Z")
Table saw with a length stop installed. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [March 2, 2010, 12:27am UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/15 "2010-03-02T00:27:41Z")
I use a [utility knife.](http://constructionandmasonrysupply.com/images/utility_knife.jpg) ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [March 2, 2010, 12:44am UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/16 "2010-03-02T00:44:10Z")
Most plastics remelt when hot. The bottles are likely this type of plastic. A high speed saw blade will heat up and melt the plastic so it binds. You don’t want to use a high speed saw blade. I use a regular pointed scissors on pop bottles to cut out the bottom. A tin snips works too. I have no idea how thick your bottles are though. I’m betting the tin snips will work even if the scissors won’t. The scissors are faster though. I use an old soldering iron to melt drain holes in plastic bottles and pots. ---
**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\ **Post date:** [March 2, 2010, 3:05am UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/17 "2010-03-02T03:05:41Z")
> [@BrotherCadfael](#): > > Table saw with a length stop installed. That is what I would go with. It would make uniform cut if you turn the bottle in your hands. I am not sure how much it would vibrate though. ---
**Author:** ![Moonshiner](https://avatars.discourse-cdn.com/v4/letter/m/9fc29f/32.png) [@Moonshiner](https://boards.straightdope.com/u/Moonshiner)\ **Post date:** [March 2, 2010, 2:25pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/18 "2010-03-02T14:25:37Z")
Third vote for the table saw. Build yourself a jig with a stop and a fence and go to town. ---
**Author:** ![flurb](https://avatars.discourse-cdn.com/v4/letter/f/51bf81/32.png) [@flurb](https://boards.straightdope.com/u/flurb)\ **Post date:** [March 2, 2010, 4:24pm UTC](https://boards.straightdope.com/t/cutting-the-bottom-off-of-a-plastic-5-gallon-water-bottle/530919/19 "2010-03-02T16:24:18Z")
> [@Harmonious\_Discord](#): > > I use a regular pointed scissors on pop bottles to cut out the bottom. A tin snips works too. I have no idea how thick your bottles are though. I’m betting the tin snips will work even if the scissors won’t. The scissors are faster though. I use an old soldering iron to melt drain holes in plastic bottles and pots. I’m thinking he’s talking about water cooler bottles, which are considerably thicker than your standard pop bottle. Scissors or tin snips would be an ordeal.