Page 1 of 1

extended shackel advice

Posted: Tue Feb 07, 2006 8:20 pm
by pongo
I am going to make some for my patrol. I am curious as to the thickness of steel i should used. The general rule of thumb seems to be 2 inch longer all round. I have included a flex pic to maybe help

So, What thickness, And what lenghts to you guys/gals reckon might be the go?

Image


Thanks for the help.

Posted: Tue Feb 07, 2006 8:29 pm
by cutzook
my shackles are pretty long and are made out of 50x10mm steel flat bar. that is for a zook though

Posted: Tue Feb 07, 2006 8:39 pm
by bundytunna
is it best to weld or bolt in a bar between the shackle???
like in the middle of the 2 shackle mounts????
i jus got 11mm steel wit no bars

Posted: Tue Feb 07, 2006 8:45 pm
by Gribble
bundytunna wrote:is it best to weld or bolt in a bar between the shackle???
like in the middle of the 2 shackle mounts????
i jus got 11mm steel wit no bars
My hilux shackles are about 250mm total lenth, 200mm eye to eye, made from 50x10 bar, with a 50x50x2 box in between.

You will need the box otherwise the shackles will move from side to side too much.

Posted: Tue Feb 07, 2006 9:05 pm
by ausyota
Dont forget that with longer shackles you will probably need longer shockies or you will end up with less travel than before.
With the plate thickness over engineering is good :) go the 10mm thick and braced in the middle.

Posted: Tue Feb 07, 2006 9:39 pm
by Mark2
If your not going to weld the bolt in the middle, use a crush tube with a bolt. Nylocks are the go as well.

Posted: Tue Feb 07, 2006 9:45 pm
by chimpboy
Mark2 wrote:If your not going to weld the bolt in the middle, use a crush tube with a bolt. Nylocks are the go as well.
I think you really must weld the bolt/bar/box that's in the middle of the "H". Otherwise, the two sides can "swivel" relative to each other, allowing the spring to twist and basically just deform and weaken faster than it should. I have seen this happen.

You could weld another piece of 50x10 into the middle instead of using a bolt. 50x50x2 RHS sounds a little bit thin-walled to me to use in this application, no offence intended to anyone who has done so. The problem I see is not so much in the crush strength of the RHS as in the strength of the joint to the sides of the shackle; there's only so much strength that a weld can have with 2mm thick steel. But maybe I am being too paranoid about it.

Jason

Posted: Tue Feb 07, 2006 11:46 pm
by Snarba
the hardest bit with an MK is bending the bar to suit the different width of the spring/chassis mount...and definately weld in something between the plates as mentioned above

Posted: Wed Feb 08, 2006 9:55 am
by -Richo-
mine are the same as Gribbles, they are tough as hell i hit them on rocks all the time, the RHS is plenty strong. If your worried use 3 or 4mm wall. When you weld the inside of the rhs the flat bar will warp unless you brace it making the shackle shaped like this...

/ \
--
\ /

Crappy drawing but you get the idea, i used nuts and threaded rod to brace it when welding, search for "IFS rears" with my username and youll find the thread i did the write up about shackles on.

Posted: Wed Feb 08, 2006 7:58 pm
by pongo
Ok thanx for the heads up. Seems 50x10mm is the way to go. I will definatly use some square/pipe in the middle to stiffen it all up. As for the Bend in the Mq/k. I am aware of it and ill have to bend them in a press or work something out, but it will be acheivable.


P.S. Nice trackbar Drop Bear. Any updates ?


Cheers

Posted: Wed Feb 08, 2006 8:05 pm
by Rhett
Id definatly put a brace in the front but as for the back dose it realy matter if they twist a bit? it all depends on how much flex you want to how you want it to handle. If the front is ofset like a lux shackle you can use more than one piece of plate and weld plus bolt them together. This is what I did when I had my lux.

Posted: Wed Feb 08, 2006 8:09 pm
by pongo
Rhett wrote:Id definatly put a brace in the front but as for the back dose it realy matter if they twist a bit? it all depends on how much flex you want to how you want it to handle. If the front is ofset like a lux shackle you can use more than one piece of plate and weld plus bolt them together. This is what I did when I had my lux.

both sides are offest. But may work. Ill have to measure the offset.

Great idea

Posted: Thu Feb 09, 2006 8:46 am
by -Richo-
pongo wrote: P.S. Nice trackbar Drop Bear. Any updates ?
Its still on :lol:

Posted: Thu Feb 09, 2006 10:23 am
by Guy
Snarba wrote:the hardest bit with an MK is bending the bar to suit the different width of the spring/chassis mount...and definately weld in something between the plates as mentioned above
Keep em strait and use spacers at the narrow end (a few bits of very heavy walled pipe the same size as or larger than your spring bush would do it)

Posted: Thu Feb 09, 2006 5:55 pm
by sudso
I've heard that extended shackles tend to invert sometimes too.

Also make sure that at full flex the shockers have sufficient travel.
The opposing side at full compression can push the droop side down so hard that the leaves bow down more after the shackle can't go any further and can break the shocker mounts.

Has anyone got pic's of anti-inversion setups?

Posted: Thu Feb 09, 2006 8:46 pm
by -Richo-
you really need to get springs to suit the shackles, just putting shackles in for some lift is a waste of time IMHO. Using the same springs you have but with longer shackles they will be almost perpendicular to the chassis and more likely to invert.

At any length, you would want your shackles to be at approx. 45 degree angle to the chassis for them to be practical.

Posted: Thu Feb 09, 2006 8:52 pm
by bad_religion_au
sudso wrote: Has anyone got pic's of anti-inversion setups?
anti inversion setups are a bandaid for a shortcoming in the suspension design... work out why their inverting, either your shackles/ leaf/ spring hanger lengths are wrong, or your leafs are bent or something

Posted: Thu Feb 09, 2006 9:03 pm
by fool_injected
from ebay US http://cgi.ebay.com/ebaymotors/ws/eBayI ... 8031215688
Looking to upgrade your suspension? This is a great shackle. This is a greaseable anti-inversion Land Cruiser shackle. There are several great qualities about this shackle. Of course, grease zerk fitting allow serviceability, but also these shackle are 4" bolt hole to bolt hole. This allows a minor lift (about 1/2 inch) so it doesn't mess up your caster and pinion angles. Now, the other great thing is the three bar desgin, all of this is bolted together to allow flex, yet the positioning of the center bar keeps your shackles from inverting at full flex. Lift springs are known to do this due to fact that they have more arch. The shackles feature 5/8" greaseable bolts with nylock nuts and the side plates are made of steel plate which has been gold zinc coated


Image

Posted: Fri Feb 10, 2006 12:20 am
by ISUZUROVER
chimpboy wrote:
Mark2 wrote:If your not going to weld the bolt in the middle, use a crush tube with a bolt. Nylocks are the go as well.
I think you really must weld the bolt/bar/box that's in the middle of the "H". Otherwise, the two sides can "swivel" relative to each other, allowing the spring to twist and basically just deform and weaken faster than it should. I have seen this happen.
No it doesn't need to be welded. Landrover military shackles have a tube and a bolt joining the two sides, and the sides do not twist relative to each other (click link for big pic).

http://www.outerlimits4x4.com/PHP_Modul ... hp?id=3383
Image