Friday, November 13, 2009

Pathfinder - Front Recovery Points



When we fitted the new bullbar to the Pathfinder, we had to remove the factory recovery points from the front of the car. The bullbar's brackets used the same bolt-points to the "chassis", and could not accommodate the old points. Because we're going to be doing a lot of sand driving at Christmas time, we needed to sort some new points out ASAP, lest we get stuck on the sand and need a recovery (or, more likely, need to recover a certain bogged Pajero).

A couple of weeks ago I dropped in to see the team at DNC Metal Works here in Cairns, and had a chat about making up a pair of custom points. Because the Pathfinders don't have a separate chassis (they're a monocoque design), I wanted the two points on each side so as to equalise the snatching loads across the entire front of the car. Of course, the sides are slightly different - the driver's side has 4 bolts, whereas the passenger's side only has 3.

Duncan measured the car up, sketched up a design that he thought would work, and let me know that he'd get them lasercut and fitted up to the car. Earlier in the week we arranged for me to leave the car with them yesterday, and they would get the points fitted up. The job was slightly complicated by the fact that because the points will sit outside of the bullbar brackets, they needed to make up a 4mm spacer to sit behind the rear two bolts (which the bullbar bracket doesn't use) so the whole thing sat level. This also meant that Duncan needed to source some brand new, slightly longer bolts to allow for the extra thickness. As an indication of the quality of the rest of the job, the new bolts are attached with both flat washers, and spring washers, to stop them coming loose.

You can (just) see the sliver of silver-coloured spacer in this pic of the back of the passenger-side point:



I picked the car up yesterday afternoon, and am rapt with the result. The points themselves are very hefty. They're just made out of normal mild steel (not a high-tensile steel), but being 10mm thick should be more than capable of dealing with the forces involved. Indeed, the metal of the car that they bolt onto is much thinner, although it is heavily braced. Some quick back-of-the-envelope calculations worked out that the driver's side point (with the 4 bolts) should be good for around 6.8 ton (using a safety factor of 5), and the 3-bolt passenger side, around 5.16 ton. By using the load-balancing bridle strap between the two points, the combined capacity will be 8.4 ton (allowing for a 30% reduction in capacity because of the side-loading introduced by the bridle). Given that an 8000lb snatch strap has a breaking strain of around 3.6ton, that leaves us with a good safety margin that gives a good assurance that the strap will break well before the metal will be affected.

The points do stick down a fair way, but that's to ensure that they will clear the bullbar brackets (which also stick down a fair way. Duncan and I discussed this when we were designing the points, and couldn't find any way around it. They don't hurt the approach angle too much though, and even if they do touch down, they're nicely rounded on the corners so the car should be able to ride up over them anyway.





All in all, I'm very impressed! Can't wait to try them out!

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