Big Bertha

I started with two 5 gallon water containers. I cut to bottom off one for the nose cone and glued it to the bottom of the other bottle that will be inverted and used for pressure. I used Goop House Hold Adhesive. This now gives us a nice long rocket body.

The next job is to make this big monster compatable with the Bigfoot Rocket Launcher System, without modifing the launcher. An easy solution was sent to me by customer Kim's 10 year old son (I'll get your name later) who said, "Simply attach the neck of a compatable bottle to the neck of another bottle that is incompatable".

I found a bottle from a 16 ounce container that was not much larger than the neck of the 5 gallon bottle. The walls of this smaller bottle were ribbed around the girth, so it was a good bottle selection for securing to the 5 gallon bottle. Cut off bottom of 16 oz bottle. Using PL Premium glue make heavy beads around neck (filling low ribbed spot) and bead around inside of 16 oz bottle. slide over and let it set (see picture to left)...I allowed 3 days cure to be sure.

Then just for save keeping, I then covered the 16 oz bottle section with filiment tape, in case it might expand and cause a leak. Then the rest is like old times. There was no leaks at all filling. I used a garden hose directly throught the launcher to fill with water. I also used an air compressor to pressurize.

HINTS: Use your shortest launch tube.....do not angle because of weight.and side loading the riser.....Presently, I've only tested at 70 psi and get great results!!!

Next time, I want to wrap the girth of the 5 gallon bottle with filiment tape (just in a few locations) to make it stronger, BEFORE adding the fins. I am currently only using 2 gallons of water. Eventually, I will work up to 2.5 gallons and 100 psi, but I'm working up to that goal.

Another hint: After you pull the trigger, it might just sit there because of the weight, but just a little lift, just to get it going will be enought to send it up on it's own power with the reduced nozzle size.

It's really amazing to see Bertha take off......the neighbors

come around to watch......today Bertha caught a breeze, went a block away and landed (fortunetly) in the street in the neighthood south of us.....I was scared about possible damage..(not to Bertha) but to someone's property.......she went 90 degree off course, YIKES! Next time I go to the playground at the

local school, which has a wide open space.

This really is a CLASSIC LAUNCH that EVERYONE will dare you to do.......they love it......really, how many people launch this size rocket on a regular basis beside me? I want to know if you try a Big Bertha too.

BIG BERTHA ROCKET INFO