Rollcage tied to frame issues (1 Viewer)

[BrianSanDiego]

Whats up guys!
So I'm currently building up a Metaltech roll cage kit in my '73 FJ40. I am going to mount the seats and harness to the cage, and the cage to the frame. I have the Metaltech frame tie in kit to use for that.

I just read, and it got me thinking , that there can be issues when you tie a cage to the frame. The frame flexes but the cage doesn't, which might cause problem with cracks in your welds or the frame.

I have been planning to tie the base or the A-pillar and C-pillar down to scab plates on the frame. But, should I possibly consider only doing the A and B pillars? Or even only attaching the B pillar to the frame, so I don't have a rigid span connected only at the front and back of the flexible frame?

I'm sure some of you have dealt with this type of stuff so share the knowledge!

Thanks a lot, Brian.

And a crappy phone pic of the progress...

 

[BellyDoc]

I don't know what the MT kit parts include, but some folks will fab bushing mounts to the frame and then 2 sided flanged mounts through the body. The body is captured in a bolted sandwich between flanges and the extension below the body goes to a tube type urethane bushing which through bolts with tabs on the frame.

Personally, I say weld to the frame. The 3D strength of the cage will stiffen the portion of the frame significantly between the A and C pillars.

 

[fj40forlife]

Hey, A lot of people put a poly bushing like doc said. But I like to tie it straight to the frame. It stiffness your frame. I havent had any problem with it. and it helps from your body going all crazy when you wheeling. You could open and close your doors =)

 

[BrianSanDiego]

Right On!
Thanks for the info guys. Looks like I'll go ahead as planned.
Brian.

 

[kling-on]

On my 60 I could only do A and B helped body flex ALOT no bushings straight to the frame ... well realy the slider but there on the frame .. my cage used to "bouce" alot and the doors would not open sometimes when I was flexed out

 

[zornff]

I welded my tie into the frame, and then bolted the cage base to the tie. No issues after 3 years. On a side note, the 2 center bars in the front of your cage are exactly like i mounted mine, but if i had it to do over i would put the bends over head instead of over the windshield. Just sayin'.

Mike

 

[BrianSanDiego]

Thanks,
Hey Mike, so do are you hurtin' for head-room or what??? I'm running Mastercraft seats, and it seems like I'll have enough head room but who knows...
The bars are just tacked in and its not to late to change it up.

B.

 

[zornff]

No, but i sat in one that had them opposite of mine and it made sense. After the fact mine don't bother me, but if they are not tacked in too tight, you might check it out.

 

[BrianSanDiego]

Cool man, thanks for the heads up. After I get the seats mounted I'll reevaluate my cranial clearance, Clarence.