FTB turtle scaffolding maker

while true do
    turtle.select(1)
    repeat
    turtle.suckUp()
    os.sleep(0.5)
    until turtle.getItemCount(2) >= 8
    turtle.dropUp(turtle.getItemCount(2) - 8)
    turtle.select(2)
    turtle.transferTo(4)
    turtle.select(13)
    for i = 1, 4 do
        turtle.craft()
        turtle.transferTo(17 - i)
    end
    turtle.select(4)
    turtle.transferTo(1)
    turtle.select(12)
    turtle.craft()
    turtle.transferTo(1)
    turtle.select(16)
    turtle.transferTo(1, 16)
    turtle.transferTo(2)
    for i = 1, 3 do
        turtle.select(20- 4 * i)
        turtle.craft()
    end
    for i = 1, 3 do
        turtle.select(12 + i)
        turtle.tranferTo(i)
    end
    turtle.select(16)
    turtle.tranferTo(6)
    turtle.select(12)
    turtle.tranferTo(9)
    turtle.select(8)
    turtle.tranferTo(11)
    turtle.select(13)
    for i = 1, 16 do
        turtle.craft()
        turtle.dropDown()
    end
end