I decided to turn my Forney into a 2-4-0, but before I do this i just wanted to ask if there is any advice or tips that can help with the conversion? anything to watch out for?
I did mine, it was pretty easy.
Take time cutting the rear wall out, I cut mine out by dragging a sharp blade backwards while holding it flush against the roof it took several passes but then all you have to do is move it forward and glue it.
Cut the metal frame way longer then you think you need then fit the parts together check it determine how your going to detail the rear the recut and file to the finish it off.
There's also a short article in the Shortline Narrow gauge gazzett mar/apr 2010 it was very helpful, I had posted pictures here but I searched "bashing my forney" but it doesn't seem to come up on search anymore.
NM
You may know this already, but the 2008 On30 Annual has a step-by-step description of the 2-4-0 bash process by Jim Shultz. Reading this is what pushed me over the edge. And back issues are still sold.
http://www.on30annual.com/
One issue that I had to address was electrical contact. The drivers by themselves have trouble over switches, and this gets worse with the stock sound system. My 2-4-0 was getting pretty finicky about cutting out and restarting when it hit a rough patch, and one solution would have been to add a bigger capacitor to the sound system. And would have been much easier if I had replaced the stock Forney sound with a full Tsunami. I opted instead to add wipers to the tender trucks, so that all 8 wheels of the tender pick up power, and that has worked fine so far.
This might not even be an issue if running on DC.
You might also check the On30 Group and On30 Conspiracy, where Alan Carroll was showing his new Forney bash, a very nice 2-4-2T loco.
manager
Manager is right about the need for pickups on the tender, without them the loco will not go over switches slow at all without stalling and if you have sound it will constantly reset even if you run fast over switches or crossings. The pickups on the tender make it run great even slow over switches