8",10", and 12" Girandolas

WARNING AND DISCLAIMER:  If you are underage, then consult with your parents or guardians before attempting any of this.  You are on your own - I'm not responsible for your actions or harm you may bring to others because of your actions.  Making the items described below  can result in injury or death to you or people in your vicinity. Some things mentioned here may be illegal to make in your city, county, state, or country so check the laws that apply to you before you attempt anything described here. These notes are not complete on purpose. If you are reading them and new to pyrotechnics, then you are making a mistake. Stop now - this page is not for you. Get a beginning book on fireworks (see Skylighter or American Fireworks News (very quick shipping)  for a start) and read up. You can't make any of this work without more information so read up or join a club or ask someone to help you.

Bucket Bottom Girandolas Have Drawbacks

You risk your fingers cutting them out and the heat from the drivers warp them

An example of a warped girandola bucket bottom after one flight

Here is a wooden girandola that has flown twice.. It is still in almost perfect condition, and if I watch where I launch it, it should last a long time. Unfortunately, I lose them a lot. Click on the above and see one take off. It is more advanced with horizontal drivers on a turntable but it is the same basic frame.

 

Oops... Ok, they aren't invulnerable. This one flew to 200 feet (notice long driver in back of photo) and then crashed into a drainage ditch that had concrete rubble (go figure - that concrete was the only hard stuff  for a mile!). Fixing it is easy - tape or replace the broken hoop and fly again!

Here is one that came in for its 10,000 mile checkup. A few patches here and there and it is ready to rock again.

 

To make a cool girandola (ok.. a small one but still cool), get a wooden needle point frame from a hobby store. The one above is 10" in diameter and costs a buck twenty - you can get 8 and 12 inch versions for about the same price. Bigger versions start getting expensive so at some point you will need to start bending your own wood. But let's stay with the easy stuff for now! 

 

Drill out the rivets in the outer ring, trim the wood until the outer ring, when butted together, is the same diameter as the inner ring. Tape and glue so you have two rings of the same size.

 

Here are the two rings - glue spacers made from popsicle sticks (iced treat sticks) - these are about two inches long. If you glue them right, you will have a strong basic frame.

 

Run bamboo kabob skewers beside each standoff and across the frame. Tie with strong cord and glue the string. Put a 1/4" tube in the center and hot glue it in place. Make a launch rack from some 2x4, plywood, and 3/16 music wire for a pivot (or a big nail with the head lopped off). Use Class C rocket motors, Estes B level (or so) motors, or 3/8" or 1/2" end-burning homemade motors on this. Quick match them so they ignite at the same time. Click on the above image to see a flight with two Estes A8 motors. Notice the hard landing on cement with no harm done.

 

Here is the same frame with two long drivers, two headers and two whistles added onto it. The drivers need to be tied and it will be ready to fly. It could take a few more things. How about a couple of lances or a sparky set of drivers to get it spinning or some bigger headers and a couple more drivers? Make one and have fun tinkering!

OBIT: The above frame is now missing in action and presumed dead. It was flown with the configuration that you see above and it worked perfectly. But it landed far down wind in a farmer's field and couldn't be found. <sniff>

 

EPILOGUE NOTES:

Drivers in the video in frame 2 (also seen here):

1. 2 motors - 5/8" x 8"
2. 5 grams oiled kitty litter for nozzle mix
3. 6 gram 3:1 (BP:charcoal) delay at the 3" point
4. No spindle used. Cone base and ram only.
5. 7/64 nozzle bored after pressing.
6. Nozzle extended 1/4" into the grain.
7. Fuel was 75/15/10, Service Chemical charcoal, Ball milled 3.5 hours. It was wetted slightly and allowed to dry (to keep down the dust). It takes about 54 grams of fuel for each 5/8 driver not counting the 6 gram delay portion.
8. Total weight of each driver is about 98 grams.
9. 2 whistles that were 2.5" grain open whistles with +12% Ti.
10. Two drivers and two whistles on a 10 inch frame make it happen.