Quote:
Originally Posted by Utemad
No, the reason not to use them is simple, they are not rated and are not strong enough
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Quote:
Originally Posted by Utemad
No, the reason not to use them is simple, they are not rated and are not strong enough
Quote:
Originally Posted by DiscoDave
Dave do not drill holes through your chassis rails,trust me youll regret it.
I was talking about the recovery hooks you can buy from any 4wd or auto store. They are rated to 10000lbs and stamped as such. The ones DiscoDave said to put under the chassis rails. Although like you I am not keen in drilling any new holes.Quote:
Originally Posted by dobbo
Well they do have "Max Load 10,000LB" stamped on them.Quote:
Originally Posted by dobbo
https://www.aulro.com/afvb/images/im...007/02/307.jpg
Is that not rated?
Quote:
Originally Posted by DiscoDave
Yes they are rated but the only way to bolt them to your chassis is to drill holes through it, unstrengthened holes in chassis rails weaken chassis rails.
We drive Landrovers, do you really think a $25 hook would be the answer? We need the $230.00 hooks for chassis mounting, bullbar mounting that hook is fine if you have a bracing/spreader plate behind the bullbar. but then your just pulling through the bullbar bolts, are they rated?
I have one of these bolted to each side of a TJM winch cradle, forwards of the chassis bolts and almost horizontally. But I'm very anti anything more than very gentle snatches, otherwise its time to winch / dig.Quote:
Originally Posted by dobbo
Rating of recovery points is a can of worms. I doubt any are rated for snatch recovery, regardless of stamped or not.
AFAIK there aren't any design codes that could be used to rate the type of recovery points we are talking about.
If we had a code, you could not rate a recovery point in isolation of whatever it is bolted or welded to.
How can any of you can say such and such is stamped x.x tonnes, therefore if an accident occurs I will be sweet?
Rudd equipment is readily available from lifting equipment suppliers, Blackwoods, etc. These are rated for lifting purposes, and are good quality.
I have used welded on Rudd equipment as lifting points on several occasions, and they were supplied prepared for welding and had specific instructions for welding. But the welds would be unsuitable for impact loads anywhere near the rating of the ring. The design of some of their bolted rings is IMHO not the best for recovery points.
When designing bolted connections, several failure conditions need to be considered. Namely: bolt tension, bolt shear, bearing on bolt, bearing on ply and tearing of ply.
Regarding the pic of 4x4de recovery point, posted near the top of this thread. Because of the location of the eye (where the shackle attaches), relative to the bolts attaching it to the chassis, the load on the bottom bolt will be approximately double the load applied at the eye.
Also the bottom bolt, which has the highest load, is assembled so the shear plane may be at the threaded section. It could be that the plate is thick enough so the start of the threads are inside the plate and not at the shear plane, but it is still bad practice.
Because of the design of that recovery point, a load applied at an angle will cause tension in the bolt, greater than the side load at the eye (due to moment and prying forces).
The shear and tension capacity of a bolt is reduced when tension is combined with shear.
Bolts in shear are not good for resisting impact loads. In tension, they can convert impact energy to strain energy.
Yes i can, the milspec series/110 has a designated set of lifting points, tiedown points and recovery points.. up to a certain point the tiedown points may be used as recovery points but the pintle hook also doubles as a recovery point. (photos to follow when I get settled in posting if required) The australian ones do not have jate rings as standard. (and I for one dont like them IMHO a good set of bow shackles, a bit of shovel work and a rearwards recovery is the go.Quote:
Originally Posted by Utemad
as a termite.. Yes you can lift a vehicle from underslung jate points but you need spreader bars and other lifting gear, there is a lot of math involved and due to the angles the required lifting gear gets rediculously large and weighty. The quicker easier and lighter setup is to strap the load to the pallet then lift the pallet.
Not a recovery point that I would use its suitable and listed in the disco1 manual as the flat tow recovery point (but shows a picture of a teardrop shaped eyelet thingy)Quote:
Originally Posted by Utemad
home bodgie, unbolt it and throw it away. I might use it as a tiedown point thoQuote:
Originally Posted by Utemad
Yep it sure is, to about 5 tons. how good are the bolts? fitting them through an unbraced, drilled section of chassis is asking for trouble, any lateral loading across the hook even more so. They would be ok fitted to a brace plate with width spacers for the retainnig bolts on an un re-inforced section of chassis..Quote:
Originally Posted by DiscoDave
These are the ones you can comonally find under the front end of toymotas, typically the ones that have chassis fatigue failures not far from those points if they have been well and truely bogged and lazily recovered (read big winch and no shovelling).
There is no point having all of your dragging gear tougher than the part of your vehicle that you bolt it to.
As someone who spent lots of time with the reccy mechs I remeber one thing when it comes to winching and recovering..
Where safe and possable, recover the crock backwards out of its own tracks.
a, you know it drove there so your on at least approachable ground.
b, its probabley down at the front so if you reocover that way your just going to plough it in before it comes out.
c. The tow point is almost always easy to get to, most recovery points are down low and will be in the muck by the time you get there.
d.normally there will be a bit of compacted ground behind the vechicle in its own tracks from where it spun in if you get it to that life is a lot easier.
For those of you who have them.. the best recovery points Ive seen are an adaptor plate that goes on inplace of the 4 fairleed rollers of the winch. They have the 4 fairleed rollers and 2 bloody great rings that are the front recovery points. The attach to your winch frame which apart from the tow pack at the rear is probabley the toughest part of your framework to pull from.
Mate.......Quote:
Originally Posted by Blknight.aus
So wrong!!!!!
The quickest way is to.....
Drive it straight into the HERC!