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Just thank God, your vehicle didn't kill anyone. Think about it from a coronial enquiries view, it's your car, your bolts, your bullbar that just killed someone. I'd be throwing away the bullbar and getting a new one installed by a reputable installer who knows what they're doing, using proper equipment.
Then I'd be buying lockers so you wont get bogged and a shovel just incase you get bogged.
Also is there a recommended life span on high tensile bolts?
pardon my stupid question, but why is a bull bar being used as a recovery point in the first place?
a bull bar is usually designed to protect a chassis or vehicle in compression, not to drag a truckload of weight in extension.
properly engineered, the bolts should be a grade that suits the shear required to not damage the chassis if you hit something..
recovery points should be elsewhere IMHO
If the car was that bogged down why not dig it out and gently tow it out. Surely if your offroad your not in that much of a hurry to get home.
It wasn't a particularly fast recovery and the bullbar itself wasn't being used as the recover point; the recovery point was attached to the bullbar at the point at which the recovery point and bar were attached to the chasis. The car wasn't bogged down either - this was a recovery exercise while on a training course on a fairly flat gravel track.
The bar is not reuseable since it is totally bent out of shape and some of the welds are cracked.
Also, there are some photos. Unfortunately they are still on my phone which recently had a falling out with my PC so they are not speaking at the moment.
Sounds like normal recovery point mounting using bull bar mounts to the chassis. That is how mine are mounted, not on the bar but using the same holes in the chassis. Very lucky. I have seen many try to recover off the bullbar and often succesfully by shear luck only.
What is the best grade of bolts to use, I know high tensile but is that grade 8 etc as ome time they can be hard to get hold of.
thats my point exactly, bolts for a sheer comression and bolts for recovery should be a totally different grade :PQuote:
Originally Posted by sam_d
To be pedantic, it's Grade 8.8 which has a Tensile Strength of 800 MPa and a Yield Strength of 640 MPa. On the other hand mild steel bolts are Grade 4.6 with a TS of 400 MPa and a YS of 240 MPa. As you can see 4.6 are much weaker than 8.8. Bear in mind the weakest link in the chain would usually be the chassis rail, which would most likely fail in bearing due to being the thinner of the two sections connected (elongation of the bolt holes).Quote:
Originally Posted by CraigE
Bolts would be readily available at any reputable bolt shop.
Cheers
Yup - and like I said in my first post, it has been checked a number of times including by two people who are members of AULRO and the guy who ran the course I was on (who has years of off road experience). If any of the people who had a look at it said anything about it not being suitable I would have sorted it out straight away.Quote:
Originally Posted by CraigE
I'm not massively knowlegable or experienced (hence being on a training course) so I've only got the experience of others to help and guide me.
Okay, fairy nuff :)Quote:
Originally Posted by incisor
But, my point is that if it was installed like that and at least three people who have vast amounts of off road experience all said it was okay then who am I (as a newbie) to argue? :)