enveetee

Hi Firstly, I have never owned or seen a 3D printer in real life I am thinking of buying a used Ultimaker. The owner describes it as 'requiring a service' whatever that means. He says the nozzle becomes blocked after about an hour of printing - he says a new nozzle should fix it. I am suspicious about this as surley the nozzle is just a heated bit of brass? with a hole in it. I think, maybe the heating element (is there one?) in the nozzle may be the problem. So, firstly, I want to go and see it and get him to print something. How easy is it for me to achieve this. Can I, for example, take an SD card (it's a UM2) with some sort of file/instructions on it and pop it in and let it print. If so, what file? Where can I get (download?) it from. Thanks in advance Nigel