CSX 2000 Roll Bar 'Test' - Circa 1964

[mickmate]

You can see from this shot the 3/4 square tubing with a light wall used to mount the rear brace of the bar. The tube has been drilled through with fairly large bolts now much stronger than the tubing so that are also trying to crush it when you do them up and remove so much cross section it weakens it considerably. Originals used nut serts through only one wall that were very small and to my engineering brain don't look up to the job though I haven't calculated their combined shear strength. This tube is also poorly triangulated partly with the top trunk tubes that are not only bent to fit the body they are held in place with small tabs so they can be bolted in after a one piece trunk has been installed. Effectively a tack welded bracket. My solution to that was heavier wall tube and to weld in sleeves for the bolts that now act as a crush preventive and make the tube stronger than it originally was there. I hope this isn't considered a thread hijack and it all seems on topic to me. Shall I continue or start a new thread?