Bogie needed

Hello, and welcome.

Yes, my friend and I have built a model of an 8f, but we've been running into trouble with the driving bogey. Whenever the engine runs onto a sharp curve, the rods pop out of the cylinders.

What i'd like to know is, is there an existing driving bogie around here with eight wheels and built-in cylinders and steam pipes.

You just need to add the correct tags to the loco config to stop the bogie rotating. Make sure you've numbered your bogie attachment points correctly too. a.bog0 should be under the first driver, a.bog1 under the last driver (one of these two will likely be invisible) and then higher numbers for any pony trucks or bogies.