Boxed angle sections of 2 in. x 2 in x ¼ in. are also satisfactory for bearers, but should also have gussets stays inserted before “boxing”. In construction of a caravan in interior fittings, it is essential to use screws rather than nails. To travel a short distance on a very rough road, inside a caravan, is very interesting. Its is amazing how the caravan appears to move and sway, and this action will very soon effect nails, inasmuch as they will lose all holding power and very soon doors will not close correctly and furniture will sag out of square.
To stabilize the caravan it is essential that a full length and full width steel chassis be fitted for although the steel is heavy it is really the foundation of which the caravan is built, and it does not pay to sacrifice strength at this point. For a caravan over 14cwt. in weight , 3 in. x 1 ½ in. channel main bearers with 2 in. x 2 in. x ¼ in. or 3/16 in. angle iron section for braces or struts can be relied upon. However , it is highly important to use gussets stays for reinforcement at any point that the main bearers are cut off or bent. These gussets may be of approximately 1 ½ in. x 3/8 in flat steel, in 12 in. lengths, electrically welded in position.