Rule 3.S question(s)

[4-barrel Mike]

I've found that with enough reading, the rules become clear.  I think that my current confusion is caused by ignorance of the terminology....

"All traction bars and trailing links shall have a metal sling near the front attaching point with a minimum of 1/4" diameter."

My rear suspension consists of a traverse buggy spring held in position by ladder bars, each of which have two bolts at the axle and one at the forward attaching point.  

Do trailing links have just one bolt at each end?  For tech purposes, are my ladder bars considered trailing links?  (Notice the ignorance)
  
If not, would "slings" be recommended anyway?  I'll probably do something, even if not required.

Ok, next part of the question: "metal sling....with a...1/4" diameter" to me connotates round, like steel cable???

I mocked up a loop of cable using red 10-gauge wire (see Cable lower view.jpg & Cable upper view.jpg) through the x-member & around the forward end of the ladder bar.  This doesn't seem really viable, so...

I mocked up a bar under both ladder bars running from one leg of the x-member to the other (see Strap lower view.jpg and Strap upper view.jpg) - currently 1" x 1/8" for ease of mock up.  This seems like a better solution than using cable.  Does it meet the letter of the rules?

Any thoughts, comments, criticisms welcomed.

Mike

[Sumner]

Just remember that if that joint would break and the rear could move rearward you don't want it to be able to go past the sling and drop down and catapult the car. 

There are a number of ways people take care of this.  In your case if it was me I think I would weld a small length of tubing that would be attached to the upper and lower ladder bars right behind the pivot point.  Then run a cable from the frame through the tubing and back up to the frame.  Now if the joint failed the cable would hold the ladder bar up and limit it's rearward movement.

If I'm not seeing your application correctly then ignore this or maybe you will get some better tips.

c ya,

Sum

[stratman59]

 you could try to design something like this on your ladder bars
this is a chassis engineering ladder bar
hope this helps
rob

[hitz]

If the ladder bars or 4 bars are enclosed by a full belly pan do they still need straps? Is it meant to keep the bar from pitch poling? What is the intent of the rule?  If one of the bars break at the attach point isn't it going to let something steer itself? The cable attachment ( didn't RICK use them) would seem to be better to hold the bar closer to it's original position. The best solution would be to design it so it didn't break.

  Harv

[4-barrel Mike]

Spent some rethinking what I was trying to do and what Sum suggested and came up with this:

1/4" cable, looped at each end with crush-type clamps (whatever their technical name).  Ran it between the bars of the ladder bars and bolted to the frame with 3/8" bolt & nylock nut: snug but not overly tight.

I didn't think that limiting rearward motion of the rear end was needed: with the traverse rear spring mounted in a heavy metal channel (Model A rear crossmember), to move at all rearward would mean that I've had a major (catastrophic?) failure somewhere and keeping the rearend from moving rearward 2" or so not improve the situation appreciably.

If this set up meets approval, I'll make up some nice thick (not fender) washers.

Do I need grade 8 bolts?  Are aluminum cable clamps acceptable?

TIA.

Mike

[stratman59]

looks good to me i would use grade 8 hardware.
the crimp clamps should be alright if make thick washers
and tighten them down good on the cable.

[Bob Drury]

Once again I offer this friendly reminder to those seeking technical advise:  scroll back thru the archives of this site.  Many of these issues have been discussed at length previously with some great suggestions and answers by those "in the know".  I am not trying to stiffle new discussion, rather remind us all of the wealth of information that Jon has generously provided us with by hosting this site.  And to you Newbies (and Oldbies) out there, take the time to go to the home page and you will see how easy it is to help support this site.  Jon would , I am sure, appreciate any financial donations, and a letter of thanks to accompany it would probably add a nice finishing touch..............Bob

[4-barrel Mike]

Bob:

   I read that advise from you when you posted it six months or so ago and have tried to take it to heard.  

   I searched:

ladder bar
traction bar
trailing link
sling

with no results that answered my questions.

    Did I miss an obvious search?    

Mike

[Bob Drury]

Mike, the problem is that most of the posts including this one  start out about something else.  I am as guilty as anyone of wandering off track.  Maybe in his spare time Jon can figure out a better archive system.