if anyone has any links with step-by-step help with solids in contact for dcg can you please let me know?? also, any other topics would be greatly appreciated (interpenetration, intersecting planes, geological geometry, oblique planes)
there's a sidebar to the left with a load of topics on it...i found the ones on skew lines and lines of intersection good :)
T4.ie is very helpful. On the left side of the page click DCG, then teaching resources, and finally core geometry. There are tabs on the top of the page (it will open on Descriptive geometry of Lines and Planes, that has a power point on ablique planes that I thoroughly recommend, there is also a good powerpoint on skew lines and intersecting planes) choose the tab that reads "projection systems and you'll find a power point as well as series of questions and solutions for solids in contact.
There is an excellent channel on YouTube for DCG links, check out Etta.ie and follow the links.