Snow Arch

Step 5 Topping off with a Keystone

Keep your arch growing until you have a space approximately the shape of a triangle on the top. This wedge piece is call the keystone. This locks in the arch and makes the entire arch lean against itself, thus eliminating the need for your entire support system. This piece needs to fit perfectly. After this piece is placed, it is your last chance to true up the arch. Make any serious adjustments now before the support system is removed.