I suppose everyone thinks that this is a dumb question to ask. The dynamo was bead blasted and lightly nickeled on the inside also. Basically I'm not sure how the dynamo will be effected by this procedure.
Wade
Wade my thinking is. That when an item is electro plated, all surfaces that are not covered or plugged will receive some coating. Only the parts that matter will normally have been polished (or bead blasted for a more mat finish). I can't see that it makes any difference if the inside has received the same treatment. Could be a problem if it was powder coated!!
Should be fine but ideally you would need to use a Pole Shoe Expander when fitting the field coil to ensure maximum flux flow. However I know people who haven't used them and its still worked.
