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It's about as simple a shuttle design as you can get and that's great because it's the kind of thing you can make quickly out of a business card. Or if you are teaching someone and you just need a short length of thread you can use the plastic tab off of a loaf of bread.
Flat shuttles are great for projects that take an enormous amount of thread or projects using huge quantities of beads. Their one big drawback is that the thread is on the outside of the shuttle and that means that it can easily get dirty.
Post shuttles are oval with a clam shape where the top and bottom sections called blades come to a rounded point at the front and back and the points of the blades touch at the tips. They may have a narrow point or pick or flat hook at the front used for joining. The thread is wound through the tips and around the post in the middle that holds the 2 blades together.
In switching from tatting rings to tatting chains you often have to shorten your thread which means re winding and when you switch back you need to unwind more thread. When working with beads the beads need to be added onto the shuttle by walking the shuttle over the thread and spacing the beads out along the length of the thread. Sometimes when you are tatting the thread instead of sliding over or under the shuttle, will slip through the tips of the blades.
Post shuttles can be made in a wide variety of materials and designs and can be very decorative making them a wonderful collector's item.
Bobbin shuttles have the same general shape as a post shuttle, but instead of a post they have a bobbin and the tips are closed in. The bobbin, in most cases, is removed for winding and depending on the type of bobbin and the type of sewing machine you have, they can often be wound on the sewing machine.
When you are tatting with a bobbin shuttle you can shorten the thread length by turning the shuttle sideways and rolling the bobbin with your thumb. Lengthening the thread is as easy as pulling on the shuttle until the desired length is reached. Beads can be added all at once as they will easily roll around the bobbin.
One of the great advantages to a bobbin shuttle is that additional bobbins can be purchased. With a post shuttle the only way to use the shuttle on another project is to finish the project of cut the thread off. With a bobbin shuttle you can change thread or change projects just by popping in a new bobbin. I always start my thread by using a slip knot around the flat shuttle post or bobbin so nothing comes loose until I want it to. Once you are finished with a project, pop out the bobbin hold the thread and let the bobbin drop. Then either throw away the scrap of thread left on the bobbin or rewind it onto the ball of thread. (Wind the thread around the ball and hold it in place by tightening the slip knot around the ball. That way it keeps the thread on the ball, and you always know the starting bit is a short end.) There's no need to waste precious tatting time doing little projects to use up the thread left on the shuttle as with the post shuttles.
I began tatting with an icky metal Boye bobbin shuttle, but it was all I had, so I used it. Then I bought my first English Aero shuttle and I was spoiled forever. A few years ago (when I was young and foolish), I would have said that anyone who doesn't like using an Aero shuttle is nuts. I have since learned that some people really struggle with the attached hook and some people find the 3 inch length from hook to end is just too long, but I have long fingers and I adore having an attached hook.
How do I love thee Aero, let me count the ways. I love the weight or rather the lack of weight. One of the irritations of using a heavy metal shuttle is that I find the weight of the shuttle will unflip the stitches and create knots when I drop the first shuttle to pick up the second shuttle. I also find that the metal shuttles can make the thread black if it gets caught between the bobbin and the shuttle. Constant use causes the bobbin to grind against the inside body of the shuttle creating powdered metal. Every time a thread gets caught between them the black metal filings come off on the thread. It usually washes out, but it's an aggravation I'll gladly do without.
I love that the Aeros have a knurled bump at the back that holds the bobbin for easy winding. The old Boye shuttles had a narrow stem at the end that the bobbins also fit over for winding, but the newer metal shuttles made by Susan Bates have a stem that is too wide to fit in the hole of the bobbin.
I love that the Aeros have an attached hook at the front that makes doing joins quick and easy. I don't have to look around for a crochet hook or keep trying to poke the thread through a picot with a point of pick. Each time I need to make a join I just grab a loop and continue pushing the whole shuttle through. Quick, neat and easy.
I love that the Aeros are made of a shiny slick plastic that the thread just glides over and that the shoulders around the hook are smooth and tapered. Everything about the Aeros makes for ease of use and fast tatting. With a craft that is anything but fast, every little bit of speed helps.
In recent years the manufacture of the Aero shuttles moved from England to Germany. The molds used to create the original English Aeros were destroyed and the German made Aeros aren't as good. The dimensions are the same and it retains the knurled knob at the back which holds the bobbin, but there are changes. The plastic isn't a smooth and it has more of a matte finish that does polish up after a lot of use. The bobbins aren't held in quite as snugly on the German shuttles and the shoulders around the hook are often cut off sharply so that the thread catches on it momentarily when in use. People purchasing the newer Aeros now made by Prym in Germany under the name Inox often wonder why older tatters rave about Aero shuttles. The newer shuttles just aren't as good as the old English made Aeros.
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Another company that has made an Aero type shuttle is H. A. Kidd and Company under the Unique label. It's the blue shuttle and I bought mine at Zellers.Their shuttle is similar in style to the Susan Bates shuttle with the useless rounded knob on the back. The shuttle material is similar to that of the German Aero and it comes packaged with one extra bobbin. The unit I purchased did not seem impossibly stiff when I bought it as did the Susan Bates model, but it was a little bit stiff. All in all though it's not a bad little shuttle and I'd rate it as on par with the German Aero except of the useless winding knob.
Coats produces a similar shuttle under the Red Heart label (it's the red shuttle) and it's available in most WalMart stores, but it doesn't come with an extra bobbin. The winding knob on this one is as useless as the Susan Bates or Unique shuttles. The shuttle material is thicker, not as elastic and has a rougher surface than the other shuttles and the shoulders around the hook are cut off sharply and quite rough. It's a cheap and use able shuttle but certainly not the delight to use that the English Aero is.
I like all of these shuttles and I'd prefer to have several of these than to spend my money of more glitzy shuttles. I can use them, break them, give them away or lose them and it isn't going to cost me an arm and a leg to replace them. I take very good care of my Aero shuttles and when 2 of them got broken in the same week (I'd been using the same pair of shuttles for about 15 years non stop, so it was just weakness from excessive use), hubby filled in the end where it had broken with hot glue to brace it and I kept on using them.
I love the looks of the wonderful unique post shuttles, but when it comes to tatting, give me my Aeros.