Find The Angle...?

[Derek Arita]

I want to put a rod up into the bottom of the front leg and cut it flush with the ground. I'll then fix a plate to the bottom of the rod, then attach a castor under the plate. For the life of me, I can't figure out how to come up with the proper angle for the flush-to-ground cut on the rod. How do I do that?
Also, how do I get "notifications" to work?

https://i.imgur.com/rXcjFgl.jpg

[David Walser]

Use a sliding T-bevel?

[Tom M King]

Put the whole thing on a flat surface, like the top of a table saw, and let the long leg hang off the edge. Mark it with any kind of straight edge. Works for anything with four legs.

[Derek Arita]

Put the whole thing on a flat surface, like the top of a table saw, and let the long leg hang off the edge. Mark it with any kind of straight edge. Works for anything with four legs.

Yes, I can make the bottom flat, however how would I then...wait...I think I may have it! If I insert a dowel or rod into the leg, then mark the dowel bottom for flat, then I'll be able to cut the dowel at the proper angle. Is that what you meant? To that dowel/rod bottom, I'll be able to attach a plate that will accept a castor.

[Tom M King]

That's the way I mark the fourth leg on sawhorses. I do the best I can making them, but leave the fourth leg long, then mark like this, and cut it with a handsaw.