On the Vale i am building they used the Bonora caps on the radiator and also as a fuel cap. They were also used on MGs, Riley's, Morris' ect, of the 1930s.
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As reproduction caps are around £130 I thought I would have a go at making my own. A few hours later I had it drawn up on Fusion 360.
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Its going to take a bit of time to 3d print it all , so started with a smaller part, the top lever.
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