Spinning Wheel Braking Systems
Spinning wheels look to be simple machines, but the first time you try to use one you’ll discover that they are far more complicated than they look. One of the biggest mysteries to a new spinner is how the braking systems work on a wheel. It is easiest to look at the braking systems as a spectrum. On one side you have Irish tension/bobbin led and on the opposite side you have Scotch tension/single drive, and in the middle you have double drive. All braking systems work by creating a difference in the speed of rotation between the flyer and the bobbin when you let up the tension on the yarn that you are drafting out. The differences come in as to how that difference in speed is created.
Irish Tension/Bobbin Led
This braking system has the drive band going around the bobbin and then a braking device on the flyer. Typically this is a band of some sort, mostly leather, that goes across the top of the flyer orifice of the spinning wheel. Some wheels, like the Matchless, have the brake band going around a whorl attached to the flyer. In this way the drive wheel is powering the bobbin and the braking is happening from the increased friction upon the flyer. This is a very aggressive or tuggy braking system. Because of this tug it is the easiest braking system to learn on. It also excels at spinning fat, low twist singles yarn. It is also very good for plying yarn and spinning various art yarns if the orifice on the flyer allows it. The Louet S10, S17, S90 and the Babe wheel are examples of bobbin led wheels.
You can adjust the amount of tug by increasing or decreasing the pressure of the brake band around either the front of the flyer or around the whorl. You can further reduce the pull by using a fat core bobbin or by lacing the flyer so that you can have an easier time spinning thinner yarns.
This braking system uses one long drive band, typically a cotton twine, that wraps around the drive wheel of the spinning wheel twice. One loop goes around a whorl on the flyer and the other loop passes around a smaller whorl on the bobbin. This braking system works by creating a speed difference between the bobbin and flyer due to the different sizes of the two whorls that the drive band goes around. Also the tightness of the band as it wraps around the drive wheel and the whorls impacts the braking as well. The higher the tension the more tug you will feel on the yarn. To adjust a double drive system the distance from the flyer to the drive wheel is adjustable in some manner. You adjust that distance until it just gets to the point that both the flyer and bobbin are turning when the wheel is treadled. From there you increase the tension until you have the braking action that you are comfortable with.
There are a few hybrid double drive systems out there that use two drive bands instead of one. Typically at least one, if not both, of the drive bands are poly instead of cotton string. With that system there is normally one band that is able to be tightened and another band that is static. The Majacraft Aura use this style of double drive system.
Scotch Tension/Single Drive
This braking system uses a drive band that goes around a whorl on the flyer and the flywheel on the spinning wheel. Then a separate brake band goes around a large whorl on the bobbin. The difference in speed between the flyer and bobbin occurs from the friction that the brake band on the bobbin provides. This friction can be increased or decreased by tightening or loosening the brake band. Normally the brake band has a spring or rubber band attached to the end that attaches to the mother-of-all it so that the tension doesn’t get too tight and damage the bobbin. Traditionally this tension system has the lightest take up which makes it idea for spinning high twist lace weight yarns. This is the most popular braking system on wheels today and is seen on many wheels including the Lendrum, some Ashford wheels, some Kromski wheels, all the Schacht wheels, and more. Some wheels, like the Blue Bonnet Crafty Bee and Honey Bee, are using a combination of large bobbin whorls and heavier drive band material to create a much stronger pull that is typical for this tension system.
It is best to stay with the type of brake band that is made for the wheel. However, if you are feeling adventurous, you can change the brake band size and material to change the braking action of your wheel. Just keep in mind that the braking action may behave very differently and use caution with different materials so that you do not put too much friction on the bobbin and wear a groove into the bobbin whorl.