Author Topic: Bolt on Tri Pods  (Read 1855 times)

Offline BK

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Bolt on Tri Pods
« on: January 06, 2017, 05:53:52 AM »
I'm looking to change the front end on my Altered from welded on Tri Pods to bolt on. I'm also thinking of spacing the mounting tabs out so I will have the option to move them up to an inch for adjustment.
If you don't see a problem with my plan my question's are. Do you feel 3/8" bolts would be enough or should I go up to 7/16". The chassis is CM. Would a flat tab's be enough or would you go with bent tabs like you might use at the motor plate?
As all ways thanks for your input and time. 

Offline dreracecar

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Re: Bolt on Tri Pods
« Reply #1 on: January 06, 2017, 08:18:42 AM »
3/8" is more than strong enough, properly engineered 5/16" in double sheer would work but you eliminate a safety margin. Keep the tabs close and the bent tabs dont need a bend, using the comercial tabs with the bend is fine. but I would first weld a half shell to the frame and then the tabs to that.

Offline rooman

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Re: Bolt on Tri Pods
« Reply #2 on: January 06, 2017, 10:10:32 AM »
If you are planning to have an inch of adjustment ( I presume so that you can change the roll out) you will need to space the tabs at around 2.25" or more depending on the diameter of your wishbone legs and the angle that they intersect the bushings at the frame.  As Bruce notes, 3/8" in double shear is more than enough strength wise--Indy car and F1 use the metric equivalent of 5/16" and they see huge braking and cornering loads--but with the spacer you have basically introduced an additional shear point roughly in the middle of the tab spacing. Relatively large outside diameter bushings (and spacers) would help in that area in the case of a hard landing from a wheelie etc.

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Offline BK

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Re: Bolt on Tri Pods
« Reply #3 on: January 06, 2017, 11:45:58 AM »
The tripods are made out of 1" OD round tube. I was thinking 3/4" OD for the spacers and sleeves. And yes adjustable roll out is what I'm thinking.