Bending RP1 & 2

[brainbug007]

I was reading the bit in the book about making these rails and it recommends using a friendly plumber to bend the pipes or using a vice & hammer and hoping it doesn't damage the pipe too much... Anyone got a good way of doing this without buying a £100+ pipe bender? I take it all the low end ones that are for 15mm & 22mm won't be able to do it?