Build a bottle rocket from pvc pipe and plastic 2 liter

Reply

  #1  
Old 03-29-10, 02:38 PM
Member
Thread Starter
Join Date: Feb 2010
Location: USA
Posts: 10
Question Build a bottle rocket from pvc pipe and plastic 2 liter

How do you build one of those bottle rockets out of pvc pipe,2 liter plastic bottle and some twist ties that they showed on diy network???
 
Sponsored Links
  #2  
Old 03-29-10, 04:02 PM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,515
Don't know about the one you saw, but I have one I constructed a few years back that we still use. The plastic bottle is captured in a holder (about 1/4 full with water) and you pressurize it with an air pump (I use a 12 volt pump and jumper box). When the hold-down is released the bottle shoots about 50' in the air. If this is what you have in mind I can take some pictures of the beast and post them here.
 
  #3  
Old 04-02-10, 08:30 AM
Member
Thread Starter
Join Date: Feb 2010
Location: USA
Posts: 10
Yeah that would be great. The one I seen on diynetwork used pvc pipe and zip ties for the plastic bottle holder.. You cut the pvc into 3 pieces and then attach a air nozzle..
 
  #4  
Old 04-03-10, 06:17 AM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,515
Well, mine is quite a bit different, but I'll shoot some pics and post them here for you to look at.
 
  #5  
Old 04-03-10, 07:25 AM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,515
Okay here goes. I should mention this is not my original design, but I made significant improvements to the idea:

This is an overall shot. You can see the air pressure gauge and filler valve in the foreground, the launch pad in the center, and the lanyard in the back.



Here's a closeup of the gauge and filler. You can also see the launch pad setup. The two large holes in the near end of the base are for the anchors. These are two long "wharf nails" that you can see stored in the other end. They are pounded into the ground at an angle to anchor the whole thing.



This is a shot of the launch pad with the lanyard and holddown pulled out, the "launched" position. The rope on the lanyard is about 20' long.



This is another shot of the launch pad with the release ring in the hold-down position without a bottle installed.



This is the underside of the setup showing the plumbing arrangement. There is a "T" fitting under the second clamp from the left and a 90 deg elbow under the far right. The pipe is 1" PVC:



This is a closup of the plumbing. The black tubing runs up to the pressure gauge:



This is another shot of the launch pad, gauge, and pressure valve:



This shows the launcher with a bottle in place. Notice the hold-down rod sides capture the bottle at the large part of the flange on the bottle. Any plastic bottle will do that has the proper size flange on the neck, it'll launch the smaller bottled water bottles that have the right neck on them:

 

Last edited by the_tow_guy; 04-03-10 at 08:06 AM.
  #6  
Old 04-03-10, 08:04 AM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,515
Another shot of the loaded pad:



A closer view of the hold-down:



Another shot of the hold-down capture of the bottle:



This shows the launch pad with the rubber grommet and shims removed. The black fitting installs in the "t" fitting from below and the shims are used to raise the grommet sufficiently to get a good seal when you install the bottle:



The grommet and shims; auto mechanics will recognize this as a shock absorber grommet/bushing:



Shot showing the anchor pins that are driven down into the ground before launch:




And that's about it. We've been using it off and on since daughter was in H.S., about 4 years or so. We periodically pull it out to entertain the younger family members and i've taken it to our youngest's school where the kids love it. Once the bottle is installed [almost forgot, put about 3" of water in the bottle before upending it onto the launch pad] you attach your pressure source - I use a 12 volt tire inflator attached to a battery booster (jumpstart) box - you stand back and watch the gauge as the system pressurizes. I generally use about 30 psi. When the pressure is observed you give the launch command and the person on the lanyard gives it a good hard yank. The hold-down rod is jerked free and the bottle launches. You then can step up and turn off the air source to reload. I haven't tried it yet with a portable air tank as a source, but that would probably work pretty well. My only concern there would be that it would pressurize too fast to get back safely, although the valve on the tank I carry on my wrecker can be regulated so it should work. I may pull it out just to see. Biggest drawback with a tank is you are limited in how many launches you can do without refilling the tank.

Couple of important safety notes:

1. Always use with adult supervision.
2. Never stand close to the bottle during pressurization and launch. I've had pressure as high as 50 psi, but it then begins to leak around the grommet on the pad. Pressure above about 30 psi really doesn't increase the launch velocity or height achieved, so there's no need to go that high. I don't know what the failure point would be as far as pressure; I've seen the Mythbusters blow up plastic soda bottles before using dry ice and they take a surprising amount of pressure.

I've probably forgotten to mention some stuff, so anyone building one ask anything.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'