Thought I would share this project of mine with you all.
Since fitting the larger tyres to my P38 (235/85R16) the spare doesn't fit into it's usual spot anymore. This past December break I fitted the spare to the roof while we went on a little roadtrip here in SA. It worked, but isn't the ideal spot, mostly because I don't like the look and added wind resistance, but also because my windsurfing gear has to go up there in future. I started designing a spare wheel carrier for the rear in August last year and I've been spending a few hours on it here and there. This afternoon I just finalised the first design revision and sent the parts off for lasercutting. I'll document the build process here.
Spare location on the roof:
Proposed location on the rear:
I'd like to retain the original bumper in this first revision, additionally I'd also like to retain the ability to unbolt the major components and possibly update or change them in future. I'd like to minimize the amount of welding to the existing chassis also.
The carrier will attach and hinge on the chassis on the right rear corner. This will attach to the rear chassis longitudinal member here:
The chassis mount will be bolt on, with only holes drilled into the chassis, no welding. The bolt on plates will be supported on two planes and supported on the inside of the chassis with backing plates to support the load:
The standard bumper will cover all the modifications to the chassis (if I managed to measure correctly, if not, I'll have to make a plan on the fly) with only a hole in the bumper on the right hand side for the swingarm bolt to pass through, as well as holes for the fasteners where the center mount attaches to. The center mount will support the swingarm vertically in the closed position as well as supply a position for the closing clamp to attach to. The center mount attachment will be welded to the rear crossmember (round bar behind the spare wheel well and inside the rear bumper), which is removable and can thus be welded off vehicle.
Center mount attachment:
The swingarm assembly is supported by two deep groove ball bearings (replaceable) and is bolted to the chassis mount with a high tensile M20 bolt. The swingarm assembly will support the spare wheel as well as a mounting location for a high-lift jack.
The center mount will bolt to the center mount attachment through the standard bumper and give the swingarm a pace to locate into and clamp onto:
Swingarm located into center mount:
The swingarm is has a secondary locking pin that locates into the chassis mount and this secondary locking pin will also lock the swingarm in it's open position, allowing normal operation of the tailgate.
Secondary locking pin and swingarm bearing assembly:
Hopefully I'll get the lasercut parts before the end of the month so that I can get going with the fabrication!