Designing and Building Your Own Travel Trailer

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Yes, the frame is steel and heavy since the length of the slide-outs go from end-to-end. Because it is heavy, hence, both slide-outs are made of aluminum. So the design approach is steel box frame for rigidity and Aluminum slide-outs for reducing weight. Yes, the slide-outs are overlapping, perhaps, the most difficult design approach to do. However, it is possible with today's Computer Aided Design (CAD) software.