Home Distiller

Hello there. I'm about build a reflux still. I've got 1m of 54mm pipe, 1.5m of 42mm pipe, loads of 22mm, 15mm and 10mm. I'm a heating engineer if you're wondering why I have so much pipe

I'm planning on using the 42mm pipe for the condenser. Anyone got any thoughts on whether for the condenser I should use 15mm pipe inside it, or try and coil up 10mm pipe to make a graham condenser?

Colin