I am new to Illustrator. I watched some videos about image tracing to make vectors and it worked for me so far until today. If i try to make simple colours and shapes into vectors it is brilliant. Today though i have an image that uses 3 colours and a pattern. The colours i use are black, orange and dark grey. I have a pattern of thick grey lines covering 50% of the image. I played with the tracing settings for hours but it just refuses to keep the lines straight. It makes the lines rounded. Check out the first image versus the second one.
Image Trace is a great tool, but it's not perfect. Adjusting the settings may improve it but it won't be perfect. If possible depending on the design, especially one as simple as the example images you've included here you should use another method. To recreate the lines there maybe:
create a line at the angle you want (Pen or Line tool), duplicate that line and move it above the first, align the two, use the blend tool to add as many copies between the two as needed, expand them, make a background to fill the negative space and move behind the lines, create a rectangle shape with no fill and position above the others, shape build the excess areas away