The hairpins that came with my neighbor's tube axle have two cross braces. One straight up, and a 2nd one welded aat an angle about halfway forward. Most have none, or just one, and I prefer at least one close to the middle, or slightly forward of middle.
Front hairpins are left unbraced intentionally, especially with a tube axle, to allow some give when the axle moves vertically on one side only, since the axle itself cannot flex, and something has to give, so the hairpins provide that. This is less of an issue with a beam axle as the axle itself will give. Rear hair pins are usually braced because they are under more stress due to handling the torque loading from the power train.
@blues4you thanks for the explanation on tube axles as I’ve been wondering the differences other the than the obvious. As I mentioned earlier I’m considering doing away with my 4 link and using hair pins. I like the function of the 4 link but on a fender less car it just isn’t working for me. And @porkn****** thank you for starting the thread. It was perfect timing. Sent from my iPad using The H.A.M.B. mobile app