At last working dynamo

[Bob Culver]

The dyn is the 4 pole DEL model with parts not directly interchangeable with later. Identifiable by the closed end. Nothing cannot be fixed but there are a myriad dud Seven dynamos in the world. An insert could be turned up , but machining tubular pieces for press fits and bearing housings is time consumimg. And the cracks are extensive although probably OK with the light loading. I presume it has been working merily as is.It is hard to imagine what disaster would cause so much fracture and cracks. The model has two ball races; it is important these are not preloaded against each other or  the smaller rigidly located (altho not much risk as is!).
This is the model originally with a functioning Summer resistance incorporated with part of the field winding. mf you have not already found, one of the Club sites covers in detail.
If ithe winding chances to be still there and OK, most disconnect.
If stuck for an intellectual challenge ,figuring the armature winding and mode of operation of a 4 pole dyn with only 2 main brushes is no mean exercise!

[Steve Bryant]

Bob, it may have been working before I got it but I don't really know. I think that the damage was caused from the dyno having been dropped at some time.
Stephen

[Tiger]

Austin Reproduction Parts list a Dynamo end cover.

[Bob Culver]

if no one springs a correct cover could try a sealed bearing, drill holes jsut beyond ends of cracks, devise a longer tie rod, and put a plate at the cracked end.
Curiously on these dynos the main brushes are at right angles . The 3rd brush is located relative to two phantom other main brushes. Hopefully the main brushes were in optimum postion and this can be determined again, not thast anyone ever worries about it..

[Bob Culver]

Incidentally there is an excellent exploded diag of the DEL endpiece in the Woodrow book.