Even though I am new to the world of 3D printing I have heard a lot about it. But I am still green and have a million questions.

Right now I am looking to create a custom part that will fit into something that I have in my truck. i want to be able to take something that is currently there and be able to modify it (what I want printed) to connect into that to be able to get what I am trying to achieve. This isn?t an engine component or anything, it is more for air conditioning.

So if I have the current part that I want to start working with and design something different that will meet what I am looking for, how would I go about scanning that part into a software or something like that to start the design process?

Any help is appreciated.