i went the flexi track route and didn't regret.
soldered just from one side will probably work, just make sure to clean the sides otherwise solder will not stick no matter how much flux used. perhaps i did not do it in the best way but when i soldered i made sure to leave about 1-1.5mm gap between rails so molten solder is also between the rails, soldered from all 3 sides (in out and top) and then filed everything flat. i did not use joiners. managed to not melt plastic stuff. looks good to me and no noises when traversing the transitions. i was going for "modern" continuous weld style track. i havent dremeled anything, will see just how much things expand.
as someone mentioned, if you want to have the "clickety clack" noises when running your train you better go with R22 sections.
soldered just from one side will probably work, just make sure to clean the sides otherwise solder will not stick no matter how much flux used. perhaps i did not do it in the best way but when i soldered i made sure to leave about 1-1.5mm gap between rails so molten solder is also between the rails, soldered from all 3 sides (in out and top) and then filed everything flat. i did not use joiners. managed to not melt plastic stuff. looks good to me and no noises when traversing the transitions. i was going for "modern" continuous weld style track. i havent dremeled anything, will see just how much things expand.
as someone mentioned, if you want to have the "clickety clack" noises when running your train you better go with R22 sections.
