Well Tim, It appears that it is back to Coober Pedy and a bit more diggin'! Now, wot are you needing such a large dynamo for any how? Going into competition with the local utility or did you forget to pay your monthly payment? I would stick with carbon brushes if I were you. Make friends with an electrician at your nearest railway shops and get some used traction motor or generator brushes. They will give a lot less trouble than those copper thingies plus they have nice "pigtails" on them.. Jesse MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.