Miniature Dolas
(under construction)
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.
6" Girandolas That Fly Well
(sometimes spelled girandoles)
NOTE: One additional note - if pure whistle is used as described in this article, it should be launched immediately after pressing and assembly. I transported several to a FFFF event and the first day or two they flew well but by the end of the week, they wouldn't leave the stand. I've since started making them with two BP drivers and two whistles. The BP drivers are stable and always get the frame up in the air.
The following is a photo essay of how to build a miniature
girandola from embroidery hoops. If you
get enough clamps or use string to bind things you can make several of these
at a time. In a few hour's work
you can have five or six made.
List of Materials:
1. Waxed string - available from Wal-Mart or other fabric
store. You can also make your own with crochet thread and some candle wax or
paraffin wax. Warm up the wax, drop the ball of string in. Let it soak a
while. Drain and cool.
2. White or yellow glue and epoxy
3. Some 5/8 tubes - cheap ones will do and are probably better because they
are lighter
4. Whistle mix. You will need about 150 grams per dola. I use 76/23/1 with
2% mineral oil added. Add about 12% titanium (optional) after it is made.
5. A press for the whistle. Don't try to hand tamp the whistle! You can use an arbor press.
Press to at least 4000 lbs
6. Some wood to make a stand - 2x4 and 2x6
7. A 1/4" bolt for the spindle for the stand and a couple of 1/4"
fender washers
8. Screws and glue to complete the stand
9. Three or four feet of quick match. The longest single piece is about two
feet.
10. Some 6" embroidery hoops
11. Several popsicle (ice cream treat) sticks
12. 3" wide gummed tape
13. Drill and drill bits
Get some embroidery hoops. They come in very small to 14 inch or even more.
Six to twelve inch hoops seem the best.
This page is for 6" hoops. Get them from eBay or a sewing supplier like
www.createforless.com
These are 6". Two sets of hoops will let you make two dolas. The inner hoops make one, etc
Get some popsicle (ice cream treat) sticks for ribs
Cut them in half
Mark off the hoops in quarters
Glue the ends of the ice cream treat ribs onto one hoop
For the outer hoops, you have to drill out the clamps - be careful, it is easy to snarf the hoop end
You'll probably get something like the above
Take a fifth ice cream treat stick and repair the hoop so it is bound tightly together
It's not a bad idea to wind waxed string around it to
reinforce the area. You can use dental floss or
waxed string from Wal-Mart or other fabric store
Attach the second hoop to the top of the first one. Remember to use both inners
for one dola, both outers
for another.
Tie some bamboo skewers across your dola to give it some spokes
We'll use that middle hole in a second
Reinforce all joints with string. I like the waxed thread from Wal-Mart for this job
Put a 5/16 brass tube down the center. You can also use lamp all-thread.
The above tube was purchased
at a hobby store. Lamp all-thread can be purchased at a hardware store or home
store
Dab glue on all the joints and string ties
Get some 4" tubes - light ones will work - and put in 2 3/4" of whistle.
See the whistle web page on this
site for information about making and pressing whistle mix. Whistle is
very energetic so be very careful.
Pressing behind a blast shield is the safest
Here is another shot of a completed driver. The whistle has 12% atomized Titanium added.
Put some loose whistle in the head of the tube
Put a cardboard cap on the tube and close it up with epoxy
Might as well make your launch stand. Make it at least a foot high. The
spindle should be two or three
inches high. There should be a washer on the bottom and the sides of the 2x4 are
trimmed to prevent
the dola from jamming on it
This one's been used. ;-}
Put your dola frame on the launch stand. It is a handy platform for finishing the dola
These motors have about 100 grams of thrust. They weight 50 grams and will
be at an angle on the
dola so the total thrust will be pretty close to 1:1 when the dola first fires
up. We want that - it will let the dola
spin up just a bit before it sheds some fuel weight and takes off. This
technique probably won't work for a
larger dola.
Put one wrap of gummed tape around the rear of the driver. Trim about 3/4" off it.
Remove about an inch from a 6" piece of quick match
Put some glue - in this case hot glue - on one side of the paper of the quick match
Put the quick match right up into the driver making sure the end touches the whistle. Squeeze it together
Tie the nosing onto the quick match
Hot glue the three motors onto the frame at about a 10 degree angle
I like to also tie them with quick-ties
Now tie all the motors together with a length of quick match
With the motors upside down on the stand, it is easy to prepare them
Put the black match together and tape it
Put some Visco in the end of the quick match and your toy is ready to launch.
Click on the above picture for a demo flight.