Try your local Men's shed. They might not be metal oriented at the moment but probably have some members who are interested as it is an industrial area. You could use them as a base and put an advert on here to ask more MEs to come along.
Same applies to the Tees Cottage situation. Just because they have a track it doesn't mean that is all they do and if you only talk to the engine driver when he is busy firing the loco he is naturally going to be rather preoccupied with that and not able to give you the bigger picture.
Middlesbrough Men's Shed
Bradhope Road, Middlesbrough TS3 7BG, United Kingdom
We are open every Tuesday morning from 10am – 12pm. Sarah Marrison or Laura Ince-Henry Groundwork North East and Cumbria 01642 815663