Page 1 of 1

Rated recovery points - how much beef??

Posted: Tue Jan 06, 2004 3:20 pm
by FireTruck
Hey all,

looking at upgrading recovery points... got a wicked Blackwoods catalog that is full of rigging equipemnt, all rated and heavy duty gear.

Question: what should recovery points be rated to? These eye plates etc are rated from 3.2t up to 50t !!! Good thing about them is the fold flat, and have full WLL rating for pull in any direction.

So... how much beef??

Posted: Tue Jan 06, 2004 3:56 pm
by Area54
Tough question - how much beef. too many variables in each situation for vehicle and where/how you like to drive.

Prolly only one simple answer:

More than you think you will ever need, and then double it for longevity so you never find out if it wasn't strong enough.

Whatever recovey point you add to your rig, it will only be as strong as the mounting point and the fasteners used.

Posted: Tue Jan 06, 2004 10:07 pm
by beebee
In the XRCC rules (and Winch Challenge I think), Dave requests at least a 1.4T SWL on eye bolts which is (I think) a 5/8" thread.

Remember something designed for lifting has a much higher safety margin that items designed for horizontal pulling.

Posted: Tue Jan 06, 2004 11:46 pm
by MUSS
just get a couple of R.U.D points and be done with it these have a s.w.l of 4 ton +... and im pretty sure they are in that catalogue you have mate

Posted: Wed Jan 07, 2004 9:17 am
by FireTruck
Thanks. SWL (safe working limit) is a little harder to figure out as it is application specific. Most of these rings/eyebolts/etc are rated WLL (working load limit).

Problem with eyebolts is that the WLL (or SWL) is much lower if they are loaded angularly (eg. 4t axially, 1t angular)... and lets face it, in our application they will be loaded from a bunch of different directions. An eye plate or a uni-directional ring bolt can be loaded in any direction and have the full WLL.

There are starpoint eyebolts available that rotate to improve the angular loaded rating (eg. 4t to 1.5t), and the starpoint design is rated up to 6 times higher than a regular collared eyebolt.

By the way - I am no engineer, so if anyone out there can shed some more light on this stuff please do.

All points have to be compliant with rules and comp ready.

Jake - what is an RUD point?

Posted: Wed Jan 07, 2004 4:12 pm
by MUSS
FireTruck wrote:Thanks. SWL (safe working limit) is a little harder to figure out as it is application specific. Most of these rings/eyebolts/etc are rated WLL (working load limit).

Problem with eyebolts is that the WLL (or SWL) is much lower if they are loaded angularly (eg. 4t axially, 1t angular)... and lets face it, in our application they will be loaded from a bunch of different directions. An eye plate or a uni-directional ring bolt can be loaded in any direction and have the full WLL.

There are starpoint eyebolts available that rotate to improve the angular loaded rating (eg. 4t to 1.5t), and the starpoint design is rated up to 6 times higher than a regular collared eyebolt.

By the way - I am no engineer, so if anyone out there can shed some more light on this stuff please do.

All points have to be compliant with rules and comp ready.

Jake - what is an RUD point?


its a bolt on recovery point that swivels 360 degrees and can then bend flat on ya bull bar 180 degrees of movement... tried to look it up on the web last night but coodnt find it but im sure some will answer this thred and post a pic of one they are the bee knees of recovery points i recon
:armsup: :armsup: :armsup:

Posted: Wed Jan 07, 2004 4:24 pm
by FireTruck
hmmm... I actually found that all of the eye plates, ring bolts, etc that I have been looking at are made by RUD... maybe it is the brand name rather than the specific bit of gear...

The uni-directional rig bolts sound like what you are talking about. They use a single grade 10.9 bolt and swivel around 360 degrees. the ring folds flat (actually has a built in clamping spring that secures the ring in the flat position when not in use). The load ring is made from grade 80 material, and they are fully rated for loading in any direction. The 4t job looks like the choice I reckon. The 4t ones weigh in at 1.2kg's each.

To get an eyebolt with the same rating as this for an angular force you would have to get one rated at about 15t that would weigh 6kg's !!!

Posted: Wed Jan 07, 2004 4:29 pm
by MUSS
thats them :armsup: i have seen em smaller and lighter then 6 kgs tho and THEY ARENT CHEAP EITHER but worth it i recon :armsup: :armsup:

Posted: Wed Jan 07, 2004 4:35 pm
by FireTruck
Good stuff and cheap stuff is rarely the same thing...

Posted: Wed Jan 07, 2004 4:40 pm
by landy_man
could you scan some picks from the blackwoods catalogue....perhaps we could organise a group discount buy price ??

Posted: Wed Jan 07, 2004 4:47 pm
by FireTruck
I'll see what I can do...

We have a work account with them and get very good dicounts (up to about 40% I reckon). Doubt I could pull off a group buy on the work account though!

I'll call in and get some prices tomorrow.

Posted: Wed Jan 07, 2004 10:32 pm
by flat4
Scary as it is you want the strap to break before the recovery point.

If you use 8000KG straps you need the recovery point to be stronger.

Steve

Posted: Thu Jan 08, 2004 8:20 am
by FireTruck
...also wonder how hard you have to pull before my rear cross member and frame go from rectangular to trapezoidal...

Doesn't matter how high the rating on the recovery point is if it's attached to something that will fail at x tons...

Straps do wear too, and the application will often lead to failure... running it over a sharp rock, around a tree, or whatever. An older frayed strap will have a much lower SWL than a brand spanking new one.

Also a big difference between yanking out a Zook and an F-350... a 10t recovery point would probably weigh more than the entire Zook! ;)

Posted: Thu Jan 08, 2004 11:19 am
by FireTruck
Not cheap.... yup...

List price is $208 each, with work discount they end up at $135 each...

2 front and 2 rear would be $540.

ouch.

Posted: Thu Jan 08, 2004 2:43 pm
by AussieCJ7
flat4 wrote:Scary as it is you want the strap to break before the recovery point.

If you use 8000KG straps you need the recovery point to be stronger.

Steve


Straps are rated at breaking strain

The items Shane is looking at are rated at swl the difference being is that they are rated to work at all day every day at the swl straps will only do their rated strength once :finger:

IIRC Typicaly SWL is 20% of breaking strain ??? If not 20% it is still a huge margin of difference, there is a note about this in the 4wd monthly test on straps