The Catherine's Wheel is not a kite. It is an item of Line Laundry or Sky Trash or whatever your preferred term is. It flys on the flying line of a kite large enough to lift it. Some people have used them as drogues on the back of Sutton FlowForm 252's. It is an adaptation of the Ringleschlange, the German Ring Snake. The Ringleschlange is bridled diferently and is constructed differently. The Ringleschlange can be reversed, turned inside out, to either 'snake' or 'ring'. The Catherine's Wheel can't do that. The Ringleschlange is constructed from one panel per cell. In other words, one piece of cloth contains the inside part, outside part, and the 'rib' or Riser section. The Catherine's Wheel uses 3 separate parts to accomplish the same thing.
I saw my first Ringleschlange in 1991. I made one shortly thereafter. I think I have made maybe two altogether. I have made a gazillion Catherine's Wheels. I guess that means they are easier to make and easier to fly. The first plans I saw for the Catherine's Wheel were written by Don Mock and appeared in Kiting in 1994. These plans are adapted from those.
Why the name 'Catherine's Wheel'? The name Catherine's Wheel is applied to devices from many disciplines. Fireworks, electrical apparatus, and others have 'Catherine's Wheels'. Basically, a circular shaped object that spins. A legendary Christian martyr of the 4th century, Catherine of Alexandria was a woman of high rank and learning. When she protested against the worship of idols, Emperor Maxentius had her tortured on a wheel and beheaded. Nothing is known of her cult until the 8th century. She is often pictured with a spiked wheel and a book.
The Catherine's Wheel is not a difficult project, but it is tedious. It is the same thing over and over again. The concept of this page is to make each step simple and easy to do. Whenever possible, after showing the way I do a step, I will detail optional ways to accomplish the same thing. I strongly urge you to read everything before attempting to build a Wheel. Some things about this project are counter-intuitive. For one thing, the Risers seem to face the wrong way. Placing and sewing them in this manner makes them much easier to align.
Overview: The typical construction of a Catherine's Wheel uses a
continuous strip for the Inner Rim, and another continuous strip for the Outer
Rim. The Risers that are sewn between them are cut individually before sewing.
There are 3 templates that are used to construct the Wheel.The Riser Template is
used to cut out the Risers. The Inner Rim Template is used to mark the Inner Rim
for placement of the Risers. I also put a 'notch' in the top of the Inner Rim
Template to locate the Tabs that will hold the bridle. The Outer Rim Template is
used to mark the Outer Rim for placement of the Risers.
These
directions will detail a 24-cell Catherine's Wheel. Larger sizes are possible.
The smaller the wheel, the more wind it needs to inflate. The math changes with
the size (number of cells) of the wheel.
It is also possible to
vary the width of the Outer Rims and Inner Rim. One wheel was made that was 8"
deep instead of the usual 12 cm. This made it able to accept the cyalume
bracelets for night flying.
I have always made the Risers with
the bottom half the size of the top. This isn't carved in stone. But the shape
of the Riser determines the angle of the risers in the Wheel, so care should be
exercised if the dimensions are changed.
Doing the Math: The original plans I saw for these wheels were in metric. I have never found a good reason to change. Whether it is Standard or Metric, it is only marks on a ruler. It only gets complicated when it is time to calculate the fabric needs. All the conversions are here if needed.
The math changes with the number of cells used to make the wheel. We'll use the 24 cell math here.
24 cell IR = 9.5 cm OR = 13 cm Riser = 12.5 cm (these numbers will make more sense in the Templates section)
IR = 9.5 cm x 24 cells = 228cm x .3937= 89.7636" (Total inches of strip required for Inner Rim)
OR = 13 cm x 24 cells = 312 x .3937= 122.8344" (Total inches of strip needed for Outer Rim)
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48-Cell
Wheel numbers: Riser=14 cm (7 cm on bottom), Inner Rim = 10 cm, Outer Rim =
13
cm.
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Some Catherine's Wheel Theory: The reason for giving all the
numbers is to lay the foundation for the builder to do their own calculations
for different size wheels. The first time I made a 12-cell wheel, it not only
wouldn't turn, it wouldn't even inflate. The reason is that I used all the same
size parts that I would have used for a 48-cell wheel. The Outer Rim was
actually too small, even though the size of the wheel was smaller. The 48 cell
wheel uses 10 cm Inner Rim spacing, which gives a circumference of 120 cm for a
12-cell wheel. Divide by pi to find the diameter = 38.19 diameter. Now add in 2
Riser dimensions to find the diameter of the wheel with a Riser om each end.
38.12 + 14 + 14 = 66.2. Multiply times pi to find the minimum circumfernce of
the Outer Rim. If it is too small, it won't inflate.New circumference = 207.96.
Call it 208 cm. Divide by 12 cells and each Outer Rim dimension needs to be 17.3
cm, not the 14 cm I used.
Said another way, I reduced the
size of the wheel, but needed to enlarge the size of the Outer Rim
spacing.
The Outer Rim needs to be just slightly larger than its
exact calculated size for the Wheel to inflate properly.
Materials, Supplies, Tools:
1/2 yard each of 3 colors of 41" 3/4 ounce ripstop nylon.
Bridle needs 50
feet of 30 pound line.
Good ball bearing swivel, 30 pound capacity or
greater. Get it from Kite Studio or Hang-em High.
If anyone knows any good kite making supply houses outside of the USA that
should be on this page, please let us know.
gengvall@aol.com
More math: Fabric: The most common sizes of fabric are 41", 44", and
54"
North Cloth makes some that is 58-1/2" wide.
We'll do the math for 41" fabric, you can do the math for other fabric sizes.
Inner Rim = 9.5 cm x 24 cells = 228cm x .3937= 89.7636" = 90 inches. Divide
by 41", the Wheel neeeds (90/41=2.1) 3 strips of 41" fabric.
3 times 12 cm
(height of strip)= 36 cm, times .3937 = 14.17 inches. Call it 15 inches of
41 inch fabric.
Outer Rim = 13 cm x 24 cells = 312 x .3937= 122.8344 inches.Divide by 41 = 2.99 = 3 strips.
Risers = 12.5 cm. each aditional Riser = 9-3/8 cm.Should be able to get 10 Risers from each strip of 41" cloth.
Tools:
Sewing machine. Regular home machine is just fine.
Even if it only straight stitches. It would be nice if it would back up, since
there are a lot of very short seams, all needing a bar tack on each end.
#14
(90) Regular Point needle.
Good thread makes a difference! HB (or HSB) 33
nylon or V 30 polyester are preferred. Get it from Kite Studio or Hang-em High.
If you must use
thread from the sewing store, use Güterman, Mölnlycke, or Mettler Metrosene
polyester thread.
The local sewing store will have at least one of those
brands.
Friends don't let friends sew with anything by Coats &
Clark.
Posterboard or heavy cardboard to make templates.
Riser Template,
Inner Rim Template, Outer Rim Template
4 foot straightedge.
Pencil
*
Hot knife.
* Hot tacker.
* Glass table for hot tacking and hot
cutting.
* Piece of glass under or in front of sewing machine for hot tacking
Risers to Outer Rim will really speed things along.
* = Nice but not
necessary. All parts may be drawn and then cold cut, either with scissors or a
rotary cutter. Some people have problems with the fumes generated by hot
cutting.
Making the Templates: The easiest way to make the templates is
to draw a line 12 cm in from the edge of a piece of posterboard. I measure and
draw everything first, and cut later. Some people find comfort if the Risers
exactly match the angles drawn on the Inner and Outer Rims, so I often cut the
Riser first, then use it as a template to cut the templates for the Inner and
Outer rims.To make cutting the strips easier, cut two rectangles out of the left
over 12 cm strip to use as spacers to place the straightedge on the fabric for
cutting. Very Important: When making the Inner Rim and Outer Rim
Templates, use the pictures as a guide and mark the
templates Right Spin and/or Left Spin. It is very important that the angles on
the Inner Rim are opposite the angles of the Outer Rim when they
are being marked. They will be on the same angle when fully assembled.
The worst nightmare is to mark the Inner Rim and the Outer Rim with the same
angle. It means they will be equal and opposite on final assembly. It makes a
wheel that inflates but doesn't spin. At least you won't be the first one to do
it ...
To re-state the above another way: Using the drawing
supplied for laying out the templates, it makes a LEFT SPIN Inner Rim Template,
and a RIGHT SPIN Outer Rim Template. Flip over the Inner Rim Template and label
that side RIGHT SPIN.
Detail of template
diemsnions. Click on image for larger picture.
Cutting the Risers: The Risers can be cut with a minimum of waste if they are flip-flopped. Cut one right side up, the next upside down. Another great trick to make cutting faster is to place a strightedge, cut the strip, and leave the straightedge in place and put the edge of the Riser Template against the straightedge to cut the Risers.
Picture showing
cutting Risers. Click on image for larger picture.
Construction: First, cut all parts. Assemble cut strips together to make a strip long enough for the Inner Rim and the Outer Rim. The best way to do this is to put a straightedge on the table, put the strips against the straightedge, overlap by about 1/4", hot tack together, and zig-zag sew together using a lap seam. A lap seam means the 2 pieces are put one on top of each other and sewn. No folding, no re-sewing. A lap seam is easier, quicker and flatter than a flat fell seam. There are times when flat fell seams and hems are desireable. This ain't one of them. NOTE: We aren't putting hems on anything in this project. If you insist they have to be there, don't let me stop you. Go for it.
Detail of using
straightedge to align strips for joining. Click on image for larger picture.
Tabs: Cut two strips, each 1" wide by the width of the fabric. Fold in thirds length-wise to make a strip about 1/3 of an inch wide, 41 inches long, and 3 layers of ripstop thick. Sew together with a zig-zag stitch if you have it. Cut into 24 pieces, each two inches long. The fastest and easiest way to cut the tabs into 2" lengths is to use a rafter square against a straightedge. We need 24 tabs, two inches long. The more accurately they are cut, the straighter the wheel will turn.
Detail of cuting Tabs.
Click on image for larger picture.
Inner Rim: There should be several strips sewn together to make one strip at least 95 inches long. Find the Inner Rim Template. Place it on the Inner Rim and cut off the fabric on the left side. Use a pencil to draw a line on the fabric down the right side of the template. Remove the template and shift it to the right until the pencil line appears on the left, align the left side of the template to that line, and draw another line on the right. Keep going until there are 25 lines (24 spaces) Don't lose count, it can be very embarrassing during final assembly.
Detail of using
Inner Rim Template to mark sew line on Inner Rim. Notice the mistake; the left
side wasn't trimmed. Click on image for larger picture.
After drawing the 25th line, shift the Inner Rim Template 1/4 inch to the right and draw another line. Double check the count, then cut on this line. This 1/4 inch allowance is where we will join the ends of the Inner Rim to make it a circle. But that is a few steps away...
If all the lines are drawn, and the count is correct, move the Inner Rim Template to where it is centered between two lines, and use the notch in the template to position a Tab. Fold a Tab in half, so it is about 1/3 of an inch wide and 1 inch long. Position it in the notch and hot tack it in place.If you don't have a Hot Tacker, use Seamstick (double sided tape available from Kite Studio). Place all 24 Tabs, then sew in place. It is fastest to 'chain stitch' them by sewing one, then moving to the next without cutting the threads. Sew all 24, then go back and trim all the threads.
Detail of using notch
in Inner Rim Template to locate Tabs on Inner Rim. It is important that they all
be the same hight or the wheel will wobble a bit. Click on image for larger
picture.
When all the Tabs are sewn in place, find the 24 Risers. Put the wide end of the Riser up, align the left edge of the Riser with a pencil line and hot tack in place. If you don't have a Hot Tacker, the next best choice is duct tape. Seamstick (double sided tape available from Kite Studio) doesn't work well here, as it is wider than the seam. Best to hold the Riser in place with surface tape and remove it as it sewn, BEFORE IT IS SEWN THRU. Trust me, you will only sew thru tape once. Helpful tip: Placing the Risers puts the top right side of one Riser one the top left of the next Riser. Working from right to left is awkward, and working from left to right means lifting up each Riser as the next one is placed. It is much easier to turn the Inside Rim upside down and work left to right. DO NOT USE THE FIRST (double with seam allowance) LINE, start with the second. Remember, there are 24 Risers and 25 lines.
Detail of Riser
placement. Note that each left Riser overlaps the one to the right. It is easier
to turn the Inner Rim upside down, skip the first line, and put 24 Risers on
the Inner Rim. Note: This wheel was white on white because the finished
wheel was sectioned into red, white and blue sections.
Place all the Risers, and chain sew them in place as we did with the Tabs. Don't sew the last one that is on the very edge of Inner Rim. Bring that one around and place it on that first line that was left empty and sew it down. Make sure the Inner Rim is flat all the way around, with no twists. It doesn't fly well as a Mobius Strip ...
Good News, Bad News: The good news is that most of the sewing is done. The bad news is that so is all the easiest sewing ...
Outer Rim: Now comes the fun part.Find the strips that were assembled to make The Outer Rim. Use the Outer Rim Template and mark lines as with the Inner Rim. Mark lines the same way we did with the Inner Rim. Cut the left, mark towards the right. Mark all the way to the 25th line, then add 1/4 inch and mark another one. Double check the count, make sure there are 25 lines, then cut off the right end of the strip, leaving the 1/4 inch seam allowance. BTW, I tricked you into marking and cutting it upside down. When it is all done, turn it upside down (or right side up, as it were.) The 'double' line with the 1/4 allowance should be on the left end of the strip. Start with the line to the right of the 'double' line with the 1/4 allowance, align a Riser with that line, (I hot tack, but tape or smurf snot works well too) ** Smurf Snot is marketed as Keen Tack or poster adhesive. It is just a sticky putty. Kevin Shannon calls it smurf snot. It works well to temporarily hold things in place while sewing.
Sew each of the Risers to the Outer Rim individually. This means, all of the Wheel sewn so far, the Inner Rim and the Risers, is to the left of the machine. The Outside Rim is marked and rolled up on the throat plate of the sewing machine. Sew one Riser to the Outside Rim. Then remove the assembly from the sewing machine and affix the next Riser in place for sewing. This is the easiest and fastest way to do it. At the last Riser, join the ends of the Outer Rim together as we did with the Inner Rim.
The Bridle: As ususal, first, a little theory. Each leg of the bridle for a Catherine's Wheel needs to be at least 1.5 times as long as the Wheel is wide. Our 24 cell wheel has IR spacing of 9.5 cm, times 24 = 228 cm, times .3937 = 89.76 inches, divided by pi = 28.5 inch diameter. Times 1.5 = 42.8 inches. There needs to be at least 43 inches from the swivel to the wheel.
We are using a adaptaion of a Cascade Bridle. A Cascade bridle means that 1 line becomes 2 lines, becomes 4 lines, etc. Since we have a 24 cell wheel, in our case, 3 lines become 6, become 12, become 24. Have no fear, it's easier than it sounds. Using our math from above, our wheel has 3 cascades of legs, and the minimum length for each leg needs to be 15 inches.
As with anything else, accuracy counts. The more exactly the lines are made and tied, the straighter the wheel will fly. To that end end, the easiest way to make and mark the 21 lines needed for the 24 cell Wheel is to use a board. The Board I use is 22" long and 1" thick. It is my 'one size fits all' board. I use it for every size Wheel I make (except the 36 cell). On one side of the board is a line marked across the middle. On the other side of the board, there is a line across the middle, and two more lines, each 1-1/2 inches away, and on either side of, the middle mark. Just wrap the board with the number of lines needed, mark across the middle line on the back, then mark across the 2 lines on the front, then cut across, and all the lines are the same length and marked in the same spots.
This same concept works very well for stack lines between stacked kites, where accuracy is crucial.
Okay, we have 21 lines, each one 46 inches long, each marked in the middle, and each marked again 21-1/2" from the middle mark. Now we are ready to attach the bridle to the Wheel. Pick a tab, any tab, and put one end of the line thru. The knot to use is a Sheet Bend. Wrap the line around the tab, then pass the end of the line thru the loop formed by the wrap. In a perfect world, the mark on the line is just sticking out of the knot. Repeat the process, tying another Sheet Bend (okay, it's really a Half Hitch) to lock in the first one.
Take the other end of the line and tie it to the next tab. Do this all the way around the wheel. Then start the second tier of the cascade bridle by taking another bridle line and tying it in a Sheet Bend to one of the lines that goes between a pair of tabs. remeber we marked them in the middle? Those marks come in real handy right now. If yours didn't get marked in the middle, no worries. Just put the tab ends together and pinch the line to find the middle, and Sheet Bend the line on there. Keep this up until there sre no more lines. The bridle should end with 3 lines. Either splice a loop or tie one, and Lark's Head (or Prusik Knot it) thru all three lines so that their middles are in the loop. An easy way to tell is that the knots are all the same distance away from the loop.
Attach a good Sampo ball bearing swivel, and you are good to go.
E-mail me with any questions or to report dead links.