Roll bar connection [Archive]

VenturaII

10-26-2009, 05:53 PM

Anyone know who makes a similar connector? Thanks.

https://static1.pt-content.com/images/pt/2008/04/m589dg-1.jpg?t=1208977538

MCMLXIX

10-26-2009, 07:20 PM

http://www.ballisticfabrication.com/

http://www.ballisticfabrication.com/ID-Tube-Clamp_p_1467.html

SDS MACHINING

10-27-2009, 02:46 PM

SDS MACHINING

10-27-2009, 02:50 PM

I just checked out that Ballasitic website, they have it right with the alternating bolts, They have some really nice stuff .. and the price of 32.00 for those connections is crazy cheap...I would use there products no question..

VenturaII

10-27-2009, 05:36 PM

Thanks for the info.

Ratfink

11-12-2009, 06:14 AM

Here is another option.

http://www.camburg.com/fabparts.html

Twentyover

11-12-2009, 07:38 AM

We do! FYI the bolts should be alternated, one from the left side and one from the right. This increases the strength substantially. We are in process of making some of these right now for our build as well.
PM me if you wish for me to offer you pricing.

Trying to understand this. If you'e using a proper bolt for the fitting, why would alternating add strength?

John Wright

11-12-2009, 08:18 AM

Trying to understand this. If you'e using a proper bolt for the fitting, why would alternating add strength?
I think it is so that you have tension in the bolts from different directions instead of just one direction. I like to alternate bolts like that also for the warm and fuzzy that it gives me since I am not a mechanical engineer and don't know any better. I do the same thing with hose clamps....

John Wright

11-12-2009, 08:22 AM

http://www.ballisticfabrication.com/ID-Tube-Clamp_p_1467.html
These are designed for the bolts to be alternated...look at where the threads are placed....

Twentyover

11-12-2009, 01:47 PM

You'll have tension in the bolt as long as it is stretched. If the bolts are stretched in the same (parallel)direction. there should be no change in clamp force regardless of which end the head is pointing.

The fact the ballistic does it does not answer my question, why do they do it? How does it 'increase the strength substantially'? I am a mechanical engineer, and while doing seat pull testing early in my career, did some study on threaded fasteners. I don't recall anything that supports SDS's claim. I'm not saying he's wrong, I'm saying explain it to me so it makes sense.

Andrew R

11-12-2009, 03:38 PM

Correct me if I'm wrong -but most in most sanctioning wouldn't you fail tech with something like that on the cage? The rules books I have read require solid 1pc bars for nearly all of the cage.

John Wright

11-13-2009, 05:09 AM

The fact the ballistic does it does not answer my question, why do they do it? How does it 'increase the strength substantially'? I am a mechanical engineer, and while doing seat pull testing early in my career, did some study on threaded fasteners. I don't recall anything that supports SDS's claim. I'm not saying he's wrong, I'm saying explain it to me so it makes sense.Ballistic puts the threads in the opposing pieces so you would have to alternate the bolts or you would only get one bolt in....(point that I was trying to make with my 2nd post.)
I feel like I understand high strength structural bolting "somewhat", having been exposed to it here at work and on my 25th year with the company I work for....I am with you and your thought process of stretching the bolt from either direction results in a equal clamping force within the joint....what about shear? ....looks like you still have the same amount of force required to shear the bolts, no matter which way they are facing, so I think that doesn't come in play either.

The GMR

12-31-2009, 04:02 PM

GMR tube clamps.

https://static1.pt-content.com/images/pt/2009/12/yhst94167679943066_2085_590378-1.jpg

http://www.thegmrstore.com/tuclco.html

Jason

69stang

01-01-2010, 07:01 AM

It looks like an engineering solution of a manufacturing decision. Because the parts have a step in them to help lock them together and wanting equal thread depth or thread engagement in each hole which translates to equal clamping force the solution is opposing fasteners (one hole threaded & one hole thru per part). Result being both halves are the same part (ease of manufacturing). That would be my educated guess. Also throw in there reduced part count - 2 machined parts & 2 bolts vs 2 machined parts, 2 bolts & 2 nuts - had they gone with 2 thru holes per part.