With my house literally like a building site I decided to start with some of the small but critical parts of the build, rather than tackle the larger components that would necessitate me trying to work in the garden.
The sender unit mounting requires a reinforcing ring with attachments. The original had captive studs but a 4mm thread stuck on top of a mud trap like the tank hasn’t got a snowballs chance in hell next time I need to remove it so I reversed the design and attached captive nuts to the tank and will use stainless socket head bolts to fit the sender. There is a risk that fuel will seep through the threads but a drop of thread-lock should prevent this. A spare piece of 1.6mm steel plate was duly sacrificed and using a combination of hole punch and plasma cutter the ring took shape. To avoid distortion I TIG brazed the captive nuts in place.
The next sundry item to form was the filler neck. The original was an awkward size, at 50mm diameter it fell between the two sizes of exhaust pipe I happen to have in the oddments bin. Nothing else for it but to roll my own. Pythagoras helped me work out the dimensions of my sheet and I rolled it around some scrap tubing and zip-tied it into shape. Following a buzz with the TIG I rolled a flange with my bead roller and Bob’s your live in lover.
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