Sideoftheroad It is my preference to use the stretched shirt material single layer only. The added thickness does not seem to increase the burnout life. The commercial ones that tower sells for instance do seem to burnout just as fast as the single layer.
Keep in mind that the type of covering film you use of course will affect the number of heat cycles you you get from the sock material. Monocoat which requires more heat will decrease the number of cycles you get.
Also if you use a thick layer or the commercial ones which have a very thick layer with monocoat.
Usually wide open on the temperature selecter is required and that may not be enough.
One last hint on using a shrink iron The temperature is never uniform on the shoe and the hottest area is the heel region with the Toe the coolest. This can be useful to consider while maneuvering your iron in use.
Above are a few pics showing this time the Century 21 iron using the the pin technique. Also pictured is a stack of precut socks ready to go. After a little practice a sock change can be done nice and tight in about a minute.
John
