Tassel Hassle

Every once in a while I get asked how to fix the tassels that splay out on tasseled loafers.

First it is important to understand why the leather strips that make up the tassel tend to curl in the first place.

A tassel is typically made of a single piece of leather with the top twenty percent or so remaining a solid piece of leather while the remainder is cut into strips (and sometimes tapered at the end).

These are made from very thin leather, but they are still leather which means that they have a grain side and a flesh side. The grain side of your shoe upper is on the outside and the flesh side is on the inside.

Because the grain side of the leather is exposed to the world, when a shoe is made a finish is applied to protect the leather to some degree. The same thing is done to the pieces of leather used for tassels. Then the tassel pieces are rolled around and attached to a leather strand that is attached to the shoe.

Since the leather of the tassel is so thin it dries out (loses its oils) much sooner than the leather of the shoe upper. The curling is caused by two factors related to the drying out of the leather:

First, leather is denser at the flesh side than the grain side, so when the leather dries the grain side compresses faster that the flesh side. Second, the finish on the grain side remains constant so it cannot shrink, it has to curl.

So now the question becomes, how do I fix the tassels once that has happened?

In the past I have recommended applying some leather conditioner (like Lexol) to the tassels and putting a rubber band around the ends. This will add the oils back into the leather, and the rubber bands helped straighten out the curl. It wasn’t a perfect solution but it worked for the most part.

However, I recently came across a product that seems to be the perfect solution for this problem. It is called http://oldleathershoe.com/wordpress/?id=228. It comes with a leather conditioner and multiple wraps that cover the entire tassel.

I think it is a great idea for people with tasseled shoes that want to take good care of them.

Evaporation and Polishing

Evaporation plays a greater role in polishing a shoe than most people realize.

Both the polish solvent, and the water used to press against the wax, vaporize. Not only does this remove the liquid solvent and the water from the surface, it also cools the surface of the wax slightly (like sweat evaporating off of the skin of a jogger).

Another interesting aspect is that the solvent and the water evaporate at different rates. The solvent (if it is Naphtha or Turpentine) evaporates about ten times faster than water. Isopropyl Alcohol (rubbing alcohol) evaporates about twice as fast as water, and four times slower that turpentine.

The faster the moisture evaporates the cooler the surface it was on becomes (it has to do with heat energy). Countering that action when polishing the shoe is the friction heat caused by the rubbing. So the less pressure rubbing required and the faster the evaporation, the easier it is to create a smooth coat of wax.

Of course the dissolving aspect of the solvent plays a role in this process as well, partially breaking down the wax of the previous coat, and allowing the current polish to spread. The quicker the solvent evaporates in this case the better.

One of the reasons I use orange oil as the solvent in the GlenKaren polish is that it evaporates about three times faster than turpentine when exposed to air.

One of the main factors in determining evaporation speed is Vapor Pressure, which is measured in millimeters of mercury (mmHg). The smaller the mmHg the more volatile (faster evaporating) the liquid is. Measuring the vapor pressure of the following liquids at a temperature of 68F/20C we see the following:

Orange Oil = 1.43 mmHg
Turpentine and Naphtha = 4 mmHg
Water = 17.5.8 mmHg
Isopropyl Alcohol = 33 mmHg

This would make it seem like water evaporates faster than Isopropyl Alcohol, which is not true. One of the other factors that can effect evaporation speed is Hydrogen Bonding within the molecular structure. Water (H2O) has very strong hydrogen bonds, which slows down its evaporation. Water has 4 times as many hydrogen bonds as Isopropyl Alcohol. Basically what it comes down to is that water evaporates about twice as slowly as Isopropyl Alcohol.

Orange oil and Turpentine are very similar in a lot of aspects:

  • Both orange oil and turpentine are solvents and considered volatile oils (evaporate quickly). With orange oil evaporating about 3 times faster.
  • Both come from natural sources; pine trees for turpentine, and oranges for orange oil. Both are biodegradable.
  • Turpentine has a flash point of 90F, whereas orange oil has a flash point of 113F. (both closed cup). A higher flash point is a little safer.
  • Solvent ability is measured in KB (Kauri-Butanol) Value. The higher the number the better the solvent ability. Turpentine has a KB value of 56, and orange oil has a KB value of 67. Making orange oil a better solvent by a small factor of about 1.2x.
  • Orange oil cost about twice as much as turpentine.
  • Orange oil smells like oranges, turpentine does not.