[drewhoo]

Have been told by all and sundry to strengthen the front-end, also the front recovery points are very shite, as all jimny owners know, and mine had ripped open the chassis already... so time for a no-profile bar with nice strong recovery points Big shout out to bluesuzy for full inspiration http://www.auszookers.com/forum/viewtopic.php?f=14&t=29328

I'm not overly keen on going the large bars, the poor g13bb needs flat foot on nearly all kinds of terrain as it is, so no need to add another 40+kg

Get:
50x50x4mm box
2x 6mm plate
6x 10mm bolts/nylex nuts/washers
(2x eye hooks read below for design change to this)
=$40 total (yep that cheap if you avoid bunnings)

Ended up only being a couple of kilo's and seems more than strong enough for a 1t 4wd.

Build photos:

(I had previously cut down my plastic bumper, thanks to hitting a dune hard, as you can see, im sure stock bumpers could integrate this)


materials!!


clamp the plates in place, align the 3 bolt holes per side, drill the plate (pilot holes first!)


cut and grind to size (thanks to my mates paul and derek for help, garage and tools, something a sydney apartment dweller cant have...


drill for the eyes, tac weld the nuts behind in place



Weld the (now cut to size) plate to the bar. Tac weld it in place (on the car) then full weld separately, unless you like car fires and burnt garages


Wait to cool (or dont, as my fingers are painfully aware of typing this) and spray paint with flames and bling, or boring black


Swear and hate on the world while drilling one side of the chassis (with bar in place) then trying to thread the nuts inside the chassis rail...


I'm very happy with the outcome, looks like a bought one(?!) I don't think it would fit any other Jimny due to the unique contorsion of my chassis but the method is the same.

Finally happy that I have front and rear towpoints... and for sanity's sake, grind off the old shitty towpoints!

Cheers

[Scales]

nice work dude. good solution to a common problem.
Hope its touch enough, no doubt someone will chime in and say it isnt.
How is your rear points done?

[zooky08]

Looks good, but nice faceshield with the 9inch.

[Scales]

zooky08 wrote:

Looks good, but nice faceshield with the 9inch.

haters gonna hate.

[Fatzook]

Scales wrote:

zooky08 wrote:

Looks good, but nice faceshield with the 9inch.

haters gonna hate.

Yeah, but the haters saw that one coming.

[abclarke]

Fatzook wrote:

Scales wrote:

zooky08 wrote:

Looks good, but nice faceshield with the 9inch.

haters gonna hate.

Yeah, but the haters saw that one coming.

Wouldnt see much for long after that

[Scales]

I just have images of the Simpsons, the old soap box racer episode....

Bart: Wheres the safety glasses??
Homer: (without even turning head away from TV) Pffft, When stuff starts flying just turn your head...
Bart: Right gotchya!

Anywho....

Can you post a pic of the mounts up close a bit? im a bit unsure of what exactly you are bolted on to. Is it the same place a ARB bar would mount?

[drewhoo]

I bought a towbar off jimbo a while back, and the crossbar that holds the tongue is enough to wrap around a snatch

When it stops pissing down ill go grab some photos of the mount mate

[Gwagensteve]

Please take these comments constructively, but I'm not all that comfortable with this design.

Firstly, I'm convinced that those eye bolts don't have a high enough rating for the application. They look to be 1/2" to me (is that correct?) and from my research, that rates them at 1030kg with a 0˚ pull. That's WAY less than the normal shackle used for recovery (3250Kg) at 45˚ the rating drops to 257kg Do you have a data sheet on the eyes you've used? 7 tonnes seems to be a very high for the size of the nut they use. Have a look at these data sheets - I can't even find an eye bolt with a 7 tonne rating, regardless of size.

http://www.lubkerdist.com/EyeBoltRating ... ations.pdf

http://www.austlift.com.au/files/catalo ... sBolts.pdf

I've never been comfortable with eye bolts for recovery, they just don't have high enough rating.

With the eyes setup the way you have them, theres a strong possibility the eyes will be side loaded , and they're not rated for that at all.


Next, it looks like the nut has been welded directly to the tube (as in, there's no doubling plate behind it) I think you'd be surprised how easily the SHS will deform under load, especially a side load. I'd reckon a decent blow with a hammer across the eye bolt will deform the tube.

Lastly, you're asking a lot of those fillet welds, don't you think? I would have much rather seen something set through, and/ or attached in more than one plane rather than relying on the strength of the welds alone, regardless of how good the welds are. They're being put in heavy shear load, as are the mounting bolts into the chassis.

I like the concept of what you've done here, I just think there are some design issues that should be attended to. I would have brought the mounting plates around to the front of the chassis ends where there look to be another couple of holes, and braced the tube with gussets out on to the front of the chassis ends. I would also have used 3mm or thicker tube, and perhaps made my own "eye" with some heavy plate (12mm or so) that sat right around the tube.

I'm sure that for light duty recovery what you have done will be fine, but the stock front tie down is also fine for light duty recovery.

As I said, please take my comments constructively.

Steve.

(Note, edited with more specific data)

[Gwagensteve]

As an aside, bluesuzy's design is very good. Eight bolts per side, the recovery point is plate and directly connected to the chassis via the bolts - there's no reliance on welds at all. In fact, each recovery eye is independently strong enough regardless of the tie plate between them. Your design places all the strength of the recovery point on the strength of the weld.



Steve.

[stockman]

It's only four bolts per side.

[Gwagensteve]

I know what I meant

Yes eight bolts total....

It wouldn't be impossible to run those bolts right through with crush sleeves and create a double shear setup too.

Steve.

[drewhoo]

Ok I've had a few recoveries now zero problems. tbh I havent used the eyes yet out of laziness, just looping the snatch around the tube.

I agree with the physics you are saying steve, but am yet to reach a point that is heavy enough to distort, if it not good enough I'll modify the end plates to be larger and integrate the hook each side (something I would suggest anyone doing this design to do now, its cheaper than eye bolts anyway)

i do disagree that it is the same strength as the standard hooks, mine were so shit, bent on every recovery

[Gwagensteve]

drewhoo, I'll clarify that I didn't claim the stock point was the same strength, only that it is suitable for light recovery.

The fact that the stock point bends is a function of its design, and that's no bad thing, as it bends, it's dissipating force that might otherwise result in a brittle failure. Most standard tie down/recovery points are designed to bend before failure, even the massive hooks used on high GVM Chevy pickups.

Part of my concern with your design is that it's not clear that deformation can occur without putting that fillet weld into some funky loads. I guess the worst case is that the whole bar breaks away from the side plates. I guess thats unlikely, but it's a risk thats not possible with Bluesuzy's design in my opinion.

Just to be clear, I think the biggest issue is the use of eye bolts - (without more information as to their rating) the design is secondary, but I think it could be improved.

Steve.

[Fatzook]

I reckon the Eye loops used above are 0.7t rating. Not 7t. I have some here with 1" thread and they are only rated to 2.75t.

[31zook]

My front bumper will be up for sale soon

[Gwagensteve]

Fatzook wrote:

I reckon the Eye loops used above are 0.7t rating. Not 7t. I have some here with 1" thread and they are only rated to 2.75t.

X2.

Steve.

[madmacca]

Gwagensteve wrote:

Fatzook wrote:

I reckon the Eye loops used above are 0.7t rating. Not 7t. I have some here with 1" thread and they are only rated to 2.75t.

X2.

Steve.

to get a collared eye bolt with a 7t rating you need a thread size of 42mm

like has been said the ones you have are 0.7 t 16mm thread by the looks

[drewhoo]

havent had time to look, happy to go with the .7 consensus, i mustve read the engraving poorly - in which case yes they are well underrated. I'll continue not using them and just looping around the bar

[Gwagensteve]

I'm sure you are aware of this, drewhoo, but I'm going to pop it in here as there is some broad safety rating type stuff in this thread.

Looping a strap around a bar will reduce its rating by a LOT. - I assume you are looping the strap back on itself through the eye?

Whilst we have all done this, and it's not the most unsafe thing imaginable*, it's not great practice.

*I say this because at least if the strap breaks where the eye wraps over the body of the strap, at least no metal will come with it.

Considering the very small investment you have in in your bar to date, I'd remake it like Bluesuzy's.
At the very least, I'd unscrew the underrated hooks right now to avoid anyone who doesn't know better hooking a strap to one.

Steve

[stockman]

Out of interest do you think the hook would fail first or do you think the hook would pull through the tubing?

[Fatzook]

stockman wrote:

Out of interest do you think the hook would fail first or do you think the hook would pull through the tubing?

Tough call. I'd guess that it would tear out of the tube first. Its only 2.5mm and the weld effected area would be enough to see it go pop IMO.

[Gwagensteve]

Apparently it's 4mm? (looks like 2.5mm to me though)

Steve.

[Trypt]

That is deffinately more than 2.5 4mm soundss right.

[Fatzook]

Gwagensteve wrote:

Apparently it's 4mm? (looks like 2.5mm to me though)

Steve.

My mistake.

I just scaled it off my screen. Looks close enough to 4mm.

[appsie]

i use 16mm eye bolts at work,mounting them up to tie small spider lifts down on trailers,tilt trays etc.They are rated at 0.7 each

while i have seen many people use these in the past and be pretty trouble free,i have also seen some of our spider lifts turn up in a container from italy with a eye bolt allready trashed and bending at the thread from either a ratchet strap or chain and turn buckle pulled tight to hold it in the container for transport. So thats with no funky snatches or pulling at wierd at angles out fourbying

seeing as though its not a real complex bar and even timmays isnt,call this one mark1 and a practice and quickly knock up the next design that you know will be right.it will only take the same amount of time to build one thats right

All good though and good work mate

[suzi-fan-22]

appsie wrote:

i use 16mm eye bolts at work,mounting them up to tie small spider lifts down on trailers,tilt trays etc.They are rated at 0.7 each

while i have seen many people use these in the past and be pretty trouble free,i have also seen some of our spider lifts turn up in a container from italy with a eye bolt allready trashed and bending at the thread from either a ratchet strap or chain and turn buckle pulled tight to hold it in the container for transport. So thats with no funky snatches or pulling at wierd at angles out fourbying

seeing as though its not a real complex bar and even timmays isnt,call this one mark1 and a practice and quickly knock up the next design that you know will be right.it will only take the same amount of time to build one thats right

All good though and good work mate

X2 and it will be cheaper than the first one

[BlueSuzy]

Thanks for using my design as asome inspiration

I agree abit with the last posts. Rhs looks abit thin, it could bend out with recoveries. But if its 4mm, its towbar material. I'd also weld the eyebolts on so they dont turn and loosen etc. Do this. It won't take long.

If people are recovering you without doing 60mph before pulling you out, the bar should be fine. However recovering someone else may find the weak point in the bar. This is what my one was designed for, + to tidy up the front end.

If the stock sierra 12mmroundbar? tiedowns are strong enough to bend the chassis tube in a recovery, (happened to mine) those eyebolts are stronger.

[Fatzook]

BlueSuzy wrote:

If the stock sierra 12mmroundbar? tiedowns are strong enough to bend the chassis tube in a recovery, (happened to mine) those eyebolts are stronger.

One is japanese milled steel, the other is cast... Possibly in a place like china.

[BlueSuzy]

They would be forged if they are a proper lifting lug.

I wouldnt rely on cast!