Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Nick I think your torch is a magnificent tool, but too much for a job such as this, to be honest.
You have to be careful, you want to solder, not burn up the structural integrity of your brass.
The plate brass of these old engines is not so thick, so the risk of overheating it and make the brass brittle is great.
It's like hitting a tiny nail with a sledge hammer, the nail will get in, but also a big dent into your wood.
Get one of these burners as I showed, they're cheap and worthwhile the investment.

Cheers,
Danny