welding questions

[tubacity]

1. What does a triangle need to be called a right triangle ?

2. The 3-4-5 ration is used in layout work to determine what ?

3. While reading a blue print here come across these symbol W3x10 at 26'-4, what is that means ?

Thank you

 

[mr. piper]

a right "angled" triangle, is so called as it has a 90deg angle in it that can be used for marking out stone blocks etc. that would give a square edge to sit "right" against another block. right means square or correct and so on as in "upright"

the 3-4-5 ratio would give a perfect right angled triangle useful for setting out and checking a 90 deg angle.

you would have to clarify this question a bit.