My Dart Swinger Project!

Do you have a small carpenter's square? The corner is 90° you need to lay each end of the tube back at 45° to equal 90°. This way your weld will penetrate further. You want it to get to the bottom of the tube all the way around. You need to give it more room to be able to do that. Look at the pix of my tube prepped on the 8.8 thread prior to welding you will see how far you have to go to get to a 90° V notch.