The Model A came with its original front brake rod, but none of the fittings. It's an odd design - the rod is 3/16" (0.1875") but, to prevent rotation in the brake arm, it's flattened at the end. This makes it larger - it's actually threaded 1 BA, on a major diameter of 0.209".
Of course, cleaning up the thread is a bit of a challenge with the flat since many dies will not bite having three sets of flutes, or very narrow flutes, as the thin rod disappears into the gaps.
Here's my stock 1BA die:
See the narrow flutes? This next picture is another I bought:
The flutes are much wider on this one, and I managed to recover the thread and get my newly-turned adjuster knob to fit. It's made from 303 stainless steel on the lathe, milled for detent on a 1 BA mandrel in the toolpost:
The outside is cut with a deep straight knurl, slightly chamfered:
The next lathe job is the spring housing, copied from the one on the W/NG. It's a bit of 1/2" 303 round bar with a 1/4" CEI thread in one end, bored 9.5 mm for clearance on the 3/8" brake rod end:
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