S irons, tie savers, log savers, truss plates etc. All of these are tools used to keep logs from splitting or degrading. There are hundreds of styles, types and materials on the market. No matter the brand or material, they are all basically the same. A piece of metal or plastic is driven into the ends of a log to keep logs from splitting open.

The end grain of wood dries out quickly due to the structure and orientation of the wood cells in the growth rings. As wood cells dry, they shrink, causing the ends of logs and lumber to split open. As the wood continues to dry and age, these splits can become larger. If let go long enough, the split can cross the diameter of the log. I have personally seen ash logs split into quarters along the entire length of the log!

There are a number of ways to help minimize the lost due to end checking and splits. The best way to prevent this type of degrade is to process logs quickly! The log can’t degrade of it has been sawn, sliced or peeled. This is not always feasible when setting up loads, or production runs. This is where s irons come into play. These tools are on the ends of the logs to hold the wood fiber together and reduce splits from continuing. The s irons are driven in usually with a hammer across the split. Once the log is ready to be processed, the s irons are removed. Along with s irons, logs can be sprayed with wax to reduce moisture lose or covered with tarps designed to keep logs cool.

S irons, or whatever brand or style you prefer are designed to protect the investment in the logs we buy and allow us to fully utilize the wood fiber with little waste.