Loop Sticks and Loop Irons - are used to form and block loops for strap work. The blocked loops have a more finished look and are easier to tuck the tag end of a strap into than unblocked loops. The leather loop is cased and then slid over the loop iron or loop stick and set to shape with light taps from a smooth hammer or smoothing tools like a bone folder.
Loop irons are made of steel. With some bridle and harness work the loop is sewn in place on one side and stapled or tacked on the other side. The metal loop irons provide a good surface for clinching the tacks or staples.
Loop sticks were traditionally made of a dense hardwood. Sliding loops are made up and joined at the ends, then cased and slid onto the loop stick. This stretches the loops slightly and the loop forms to the rectangular cross section of the loop stick. I have started making these from a high-impact plastic called acetal. Delrin is a form of acetal.
Loop Sticks - I am making these sets up from acetal. This plastic is high-impact and carries the advantage of not marking wet leather like steel can do. The standard set goes from 1/2 inch to 1-1/2 inches and covers the eight standard strap widths. The 1/2 through 1 inch width sticks are 3/8 inch thick, The sizes wider than one inch are made from 1/2 inch stock. The standard set is $75. Some makers need widths of 1-3/4 or 2 inch widths and those sizes are sold as loose stock for $10 each. These sets are 8 inches long so a complete set can be shipped in a small flat rate Priority mail box. They have a hole for hanging or putting a lace through to keep them strung together.
Loop Irons - are used to form loops and carry the advantage of being made from steel and able to be used for standing loops with staple or tack techniques. They can also be used to slid into small spaces to set rivets against in some repair jobs as well. One disadvantage to be aware of is that the steel may cause a black staining reaction on damp vegtan leather.