Can't get the angles for Wainscotting

[NoveltyNovice]

Hi guys,

Complete novice here, but I'm attempting to add wainscotting to my stairs walls but running into an issue with cutting. I used a protractor and found the angle to be 135. I've been watching some diy videos where it mentions to subtract whatever angle you get over 100 by 180 and then divide that number by 2, equaling 22.5. Thing is, I tried to cut it at this number but it doesn't join properly. I then tried how it would cut at 45 degrees, and same thing happened. The joints join neatly if I where building some rectangle but I'm trying to connect the length (71.6cm) and the width (78cm) in an almost parallelogram type shape but it's just not happening. I tried to just divide the 135 by 2 which is giving 67.5 but wasn't able to cut it as my saw only goes up to 45 so not sure how to mark this on the wood.


Any advice?

[Grendel]

Pictures would help but I think I've got a rough idea of what you are trying to do.
First thing to do is chuck the protractor in the bin. I don't think I "ve ever really known the actual angles because it's not really necassary. You're creating a parallelogram , the top and bottom should be parallel with the stair string and the two sides should be vertical and a spirit level will do that. Simply draw it out on the wall and set a sliding bevel or cut a hardboard template nd work off that...

[fin]

one of these maybe of use
https://www.amazon.co.uk/Starrett-7-inc ... 3002&psc=1