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Am I Missing Something?

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#1 rhidmogz

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Posted 08 May 2022 - 05:07 PM

Am i missing something??

 

ive made a rollover jig believe it or not the 3rd one over the years!

 

but this time if used the front subframes mounts and rear shock mounts as pick up points this time instead of a solid bar through the car but its sitting bowed and impossible to turn and am worried leaving the car on the jig will cause undue stress. to i need to make hangers for the spit? or are my mounts not suitable?

 

 

psqtf85.jpg

 

g0sZMlL.jpg

 

bL7781q.jpg

 

5ucrX7y.jpg

 

ive already cut the jig down to gwt the centre of gravity lower is the jig itself too high? but it needs to be this tall give or take a few hundred mm so that it can turn the car completely over or am i living in cloud cuckoo trying to get the car to be able to turn completely over?

 

thanks rhid



#2 PoolGuy

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Posted 08 May 2022 - 05:36 PM

Maybe I'm missing something too, but surely the bar that goes to the subframe needs to be triangulated so that it'll support the car?



#3 weef

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Posted 08 May 2022 - 05:59 PM

I am afraid just looking a the geometery of the bars that will never turn. The tubes have to be parrallel with to the axis of the vehicle to rotate. It is start again time and redesign it.



#4 Spitz

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Posted 08 May 2022 - 06:09 PM

Looks like the top of the triangle is the weak point

#5 imack

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Posted 08 May 2022 - 06:17 PM

I agree with weef, you're never going to be able to rotate that!

#6 imack

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Posted 08 May 2022 - 06:18 PM

Double post

Edited by imack, 08 May 2022 - 06:18 PM.


#7 MacGyver

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Posted 08 May 2022 - 06:20 PM

Triangulation is the key, you've only bolted it to one axis and all the weight is going thru them. Like taking out a nail with a crow bar, no matter how big the nail the leverage is too strong without another point.
On the rotisserie without a pole it picks up near the subframe lower points at the front and parcel shelf at the back.

Good old auto correct...

Edited by MacGyver, 08 May 2022 - 06:30 PM.


#8 MacGyver

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Posted 08 May 2022 - 06:28 PM

Attached File  _20220508_202334.JPG   31.29K   6 downloads
You can see the front bracing on these pictures.
Attached File  _20220508_202356.JPG   41.6K   4 downloads
And the back on this one.
Attached File  _20220508_202440.JPG   68.72K   4 downloads
Sorry I don't have better ones but I can't find better ones to hand, but plenty on the net if you want. 😁

Ben

#9 rhidmogz

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Posted 08 May 2022 - 06:28 PM

all the weld etc are fine nothings broken 

i get the car wont turn as is atm my question is why does it seem to be sitting as it is ive coppied the look from jigs ive seen on line 

could it be down to the strengthening bar not being enough and the triangle and need two feet that extend?



#10 rhidmogz

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Posted 08 May 2022 - 06:30 PM

attachicon.gif _20220508_202334.JPG
You can see the front bracing on these pictures.
attachicon.gif _20220508_202356.JPG
And the back on this one.
attachicon.gif _20220508_202440.JPG
Sorry I don't have better ones but I can't find better ones to hand, but plenty on the net if you want.

Ben

 ahh right i can see what ive not done now! 

 

in the photos ive been looking at ive not notice these extra joists 

 

thanks ben!



#11 MacGyver

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Posted 08 May 2022 - 06:33 PM

I can get better ones if you'd like?
But if you bolt a plate on the toeboard and then a bar to the pole from each side you should be fine.

#12 PoolGuy

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Posted 08 May 2022 - 06:40 PM

Basically the bar needs three contact points, whether two are on the car and one on the jig or vice versa doesn't matter, but without massive strength it won't work as you have it. MacGyver's pics show a good example.



#13 rhidmogz

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Posted 08 May 2022 - 07:06 PM

their great thanks!

 

i can understand it in my head now a little tweak in the week and it should be good thanks guys



#14 Aly-g

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Posted 08 May 2022 - 07:47 PM

I am afraid just looking a the geometery of the bars that will never turn. The tubes have to be parrallel with to the axis of the vehicle to rotate. It is start again time and redesign it.

I'm in total agreement with weef, there is no way that's going to rotate ,the tubes do have to be parallel, as soon as you try to rotate the car the tube on the A frame will try to turn the whole frame and not the car.  time to get welding.

 

Allan



#15 postma

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Posted 09 May 2022 - 06:59 AM

some pictures as reference ...

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