After we had used our trailer in its initial mode of a bare chassis with baulks of timber to carry things on, we went to the next stage of flooring it properly and getting the folding tailgate sorted out. A front load restraining frame was also required. This took a few bouts of head-scratching and a spell on the CAD system, but we ended up with a reasonably convenient design that wouldn't cost an arm and a leg to build onto what we already had.
This shot is of the front of the trailer, with the 90 X 50 X 5mm box section draw bar, extending well back towards the front axle for support. The main frame is 50 X 50 X 5mm box section, doubled in the area of the suspension beam mountings by welding an extra length alongside the main side framing. The 12mm bolts for the suspension beams pass through the perimeter frame, and the holes will weaken the frame tubes, hence the reinforcement. Note the welded on rope hooks, really useful, wish I had some down the sides as well! Notice also that there is a recessed area within the open sections, made by welding 25mm angle inside the framing, this is for the wooden flooring which was cut to fit and varnished before fitting.
This shot is of the back end, with the folding tailgate arrangement fitted up and painted. The recessed area for the plywood floor is more easily seen in the tailgate. Note the rope hooks on the sides of the rear supports, and the stands which are bolted to box pieces underneath the main chassis. The tailgate proved to be a mixed blessing, as we could increase our volume of hay carried by running with it down, using the stays shown in the picture, but it was a major air brake, and slowed the Midi down by as much as 15mph on a windy day. This was eventually replaced with a smaller tailgate with no floor at all when the chassis was lengthened before our trip to Spain in 2000.
A shot of the centre portion, showing the Indespension Superride suspension beams and the recessed areas for the ply decking. The cable brakes and a few other features can be seen.
A close-up shot of the heavy-duty tailgate hinge pieces. These are welded-on items, and available from Indespension. They are welded all round and a piece of 14mm stainless bar was passed through to act as a hinge pin and to also support the hanging number plate board. The holes in the hinge pieces are too small as received, so will have to be drilled out if you want to use a bigger bolt or hinge pin. We eventually took the hanging number plate board off the hinge pin, made the pin in 2 short pieces and suspended the number plate board on three exhaust mounts from inside the new and smaller rear tailgate. The bent steel handles for the stands were a major cause of damaged legs while working round the trailer, and were eventually replaced by a pair of M12 bolts. The hinge pin was retained in place by a pair of 'R' clips, with a couple of turned nylon spacers between the single hinge piece on the tailgate and the outer hinge piece on the chassis, which located the tailgate laterally, so the ears on the top through which passed the main retaining bolts, would line up without juggling.
Varnished (3 coats of polyurethane) 18mm plywood in place on all the recessed areas, ready for fixing the checker-plate flooring on top. The varnish took about 24 hours to dry between coats, and was lightly rubbed down between coats. The doubled width of the perimeter frame can be seen adjacent to the wheels. We were running on 155X13 4 ply tyres at this time, giving a maximum weight of about 1800kg or 3960lbs or just over 1.75 tons imperial. We were later to change to 175X13 8 ply tyres, which raised our maximum weight to 2600 kg or 5720lbs or just over 2.5 tons imperial. The suspension beams are rated at 1300kgs each. The moulded plastic mudguards were a standard unit, and only required a decent bracket at each end to stay rigid. Side marker lights were required, just! The Midi was appreciably smaller in width than the trailer, while the Movano is about the same width. In both cases we can see the wheels and mudguards in the mirrors.
Laying on the new Ali checker-plate. Looks nice now, but in a few years what will it look like ?? Because of the sheet size restrictions, we ended up with a full sheet and bits to fill in the rest. M6 stainless steel button head screws were used for fasting into the frame, while countersunk wood screws, also in stainless were used to fasten to the wooden panels. When we lengthened the chassis in the winter of 1999, we replaced the M6 screws with M8. The checker-plate has paid for itself over and over again, and we would not hesitate to recommend it for anyone building a new trailer or re-decking an older trailer. We tried to seal the plates against the frame and wood, but realised later on that it was better to leave rain water etc to run through and away, rather than trapping it between the wood and Ali.