Re: Broken spokes

A circular band on the hub encompassing the axle or oval shaped band on the hub encompassing the axle and crankpin is a common repair for a cracked hub where the stress of the axle’s press fit in the wheel caused a crack to form, perhaps where a defect in the wheel casting made a weak spot. If I recall, RGS #42 in Durango also has a banded hub.
Brazing broken spokes was a common and excepted repair for broken spokes. This is a seperate issue from cracked hubs. Ex N&W #475 has well over a dozen spokes that were repaired by brazing by the N&W.
Part 230.114(c) covers permissible repairs for both situations.
Sec. 230.114 Wheel centers.
(a) Filling blocks and shims. Driving and trailing wheel centers
with divided rims shall be properly fitted with iron or steel filling
blocks before the tires are applied, and such filling blocks shall be
properly maintained. When shims are inserted between the tire and the
wheel center, not more than two thicknesses of shims may be used, one of
which must extend entirely around the wheel. The shim which extends
entirely around the wheel may be in three or four pieces, providing they
do not lap.
(b) Wheel center condemning defects. Wheel centers with any of the
following defects shall be removed from service immediately and
repaired:
(1) Wheels centers loose on axle;
(2) Broken or defective tire fastenings;
(3) Broken or cracked hubs, plates, bolts or spokes, except as
provided in paragraph (b)(4) of this section; or
(4) Driving or trailing wheel center with three adjacent spokes or
25 percent or more of the spokes in the wheel broken.
(c) Wheel center repairs. Wheel centers may be repaired by welding
or brazing provided that the defect can properly be so repaired and,
following the repair, the crankpin and axle shall remain tight in the
wheel. Banding of the hub is permitted.
(d) Counterbalance maintenance. Wheel counterbalances shall be
maintained in a safe and suitable condition for service.