ALS'/DLF' : your daily dose of Arcade Life Style...inside the Dragon's Lair!
I bought a long "waterpas" for that kind of work.. (nivel i think its called in english) at "Van Cranenbroek"usually they are straight and, Van Cranenbroek is cheap I also us it as a guide when using the circular saw..I have 2 of them, one of 1 meter, and 1 of 1,5 meter