# Help with engineering graphics

Please redirect me if this is the wrong place to post this, however I've been having issues with something for engineering graphics classes and need some help

I'm supposed to draw two intersecting cylinders (as shown above), but drawing them is as far as I can go. I'm not able to find the points where they intersect. This is my progress so far, is anyone able to help?

• We need more clear details on each cylinder, the way they intersect (T, Y), and the views you need to draw. Please update your question.
– r13
Commented Jan 21, 2022 at 1:03
• Added details, sorry. As far as I'm aware, it's supposed to look like this !Valid XHTML. Commented Jan 21, 2022 at 10:02
• The information you provided in the first drawing shows all three standard views. What initial information were you given for in your class? Three key points will be: a) each pipes size, B) how do they insect? (ie intersect so centerline intersect, so inverts (ie bottoms) intersect, or some other dimension, c) The angle they intersect in plan view. Oh and knowing which of the views of the intersection you would need to draw are also important. Without knowing the starting information its not likely we can direct you on how to proceed. Commented Jan 28, 2022 at 2:05

This is an approximation which would be sufficient for most cases. However if an exact outline was needed you would need to go with a more refined method, but usual not required for these views.

Now starting with the assumption that the edges of your pipe are intersecting and the centerlines of the pipes are perpendicular, you should wind up with something along the lines of the following:

Now in order to achieve this I started with the two side views as follows:

To form the basis of the plan view, extend a line from the edge of the circles as follows:

note I simply used xline vertical and horizontal and then copied over the section cuts.

To minimize line work and potential confusion trim the excess lines to the cut lines in the plan:

Now we know a couple of things. Since the pipes are of a different diameter, I do not believe you are going to get a straight 45 degree line where the pipes meet on the lower half. Also note that the larger pipes radius is less than the diameter of the smaller pipe. This means you will see the edges of intersection above and below what would be the straight edge of the pipe. In this case it is very close so the intersection line above the pipe is very small and almost straight. For manual drafting and very dependent on the scale I may even draw this as a straight line.

To simplify the intersection curve, I would simply draw an ellipse with an axis with end points where the smaller pipe intersects the larger pipe. For the other axis, it would be the peak of where the smaller pipe's top/bottom intersects the larger pipe. Find those intersection points on the right side view and project them across as follows:

Note how close this is to the edge of the circle, I will zoom in too see the difference in the right side view:

So now we have the top point, repeat this with the bottom point (which is also the two centerlines) and we get the following:

To draw the top line we draw the previously described ellipse as follows (zoomed in for clarity):

And after trimming the excess lines (kept the centreline for next step) it looks like the following:

To get the bottom line repeat the above process but use the intersection of the centerlines as your ellipse offset. It should look like the following:

Now trim the line work and remove excess line and you should get something like the following:

Now mirror the bottom ellipses across the centerline of the large pipe, and trim the straight line inside of the ellipse and you are done. Not at this scale the top ellipse looks like a straight line even though it is not:

#Update#

So I went into Inventor and drew this up to see how it compares. And we get the following shape instead: