[dsdeur]

Look into scales, you can put whatever you want in the same chart by positioning it using the same scales. https://github.com/d3/d3-scale

You can use that same scale to draw just one set of axis.

Need multiple Y axis? Create two Y scales with the same range, one X scale.

Also I think it's good to understand that "chart" is not really a concept in D3. You just get all the elements of a chart which is why it is so awesome as you get to compose your own chart just the way you like it!