3d printed engines

Have you had a look at LGB ? They make gauge 1 and may even do a chassis to suite what you need.

Hello Graham, thanks for replying.
I've looked through what lgb and piko offer and I have a Piko engine block which I've based my design on. The reason I moved away from the premade engine blocks was the price and how little space was left in the engine for the controller. I went to a model railway exhibition near Lincoln a few years ago and I saw some scratch built engines where even the engine block was hand made but I have no idea how they did it. It was very impressive stuff! Looking back I should have taken more photos!

Look up "N20 motor gearbox" or "N10 motor gearbox". They're small, but with way vastly more torque on the output than a worm-drive (which has huge power losses in the worm). They come in a variety of output speeds (based on gears ratios in the gearbox), and usually a choice of 5v or 12v rated motors (5v may be more use if going for a battery/radio system of control, need fewer volts in the batteries).
They may be powerful enough for what you're doing. If not, there are many similar motor gearboxes which are a little larger.

Thanks that looks perfect. I've ordered one from eBay so I'll let you know how I get on when it arrives 🙂

Thanks so much for the recommendation. I bought and fitted a N10 motor and gearbox and it's made a huge difference. I was a little worried about how small it is but it delivers loads of torque!

Thanks again!