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anyone build this rocker arm suspension yet?
thekafer - 11/3/04 at 03:30 AM

I down loaded a rocker arm front suspension drawing from: http://www.7builder.com/
It looked well thought out, easy to build so I've made all the bits.
So,now that I've got labour and materials tied up in them(trust me I'm my comfort zone here...)
Has anyone used this design before?
If so,how does it perform?
P.S. I tried to link to the site
Fletch,


pbura - 11/3/04 at 04:42 AM

quote:
Has anyone used this design before?


Nope

I'll help you out with that link, though:

http://www.7builder.com/7builder/Downloads/BobsShocks.html

I think it's a great way to go

Pete


ady8077 - 11/3/04 at 12:56 PM

Hi

Looks ok but is there a nylon spacer between the sides of the rocker arm and the chassis bracket?

Also i doubt SVA will like the pivot tube only held in with a spring clip

Adrian


Alan B - 11/3/04 at 01:43 PM

Good job the SVA guys have no jurisdiction in Texas then...

Seriously though, good point...worth checking....


MikeP - 11/3/04 at 10:56 PM

I've ridden in Bob's car, and it handles very nicely (I'm too big to drive it). He hasn't had trouble with anything breaking or wearing yet that he's mentioned. It does give him a lot of flexibility in choosing spring rates, etc.

I did the drawings for him - there were no nylon washers between the steel tubes and the brackets, but that or steel ones does sound like a nice addition. Not sure if it's 100% necessary as the force is all up and down, but maybe after many miles you could replace them rather than having worn brackets.

Is the diaper pin a problem for SVA if it's covered by the bodywork? It is pretty hefty at 1/8". You could always do a larger bolt or proper pin of some kind, but careful as there's a problem with space - it might be tricky to disassemble if there's too much going on.

Bob should be back from his winter vacation in a few weeks, we can ask him how it held up (he took the car with him).

BTW, to link directly to my site pages you need to use "open page in new window" - as Pete knows - to find the real page address.


Dale - 11/3/04 at 11:01 PM

Just curious as to what size tubing was used for the pushrods or links between the A arm and the rocker. My arms are quite a bit longer than normal and are made from 1x .125 dom tube but thought that 1 or .75 by 16 guage would probably be good for the rods as they are in direct compression and tension.
Dale


MikeP - 11/3/04 at 11:27 PM

Bob used 3/4" OD 1/2" ID tube. I don't think he'd did a stength analysis. He needed the ID for his rod end bolt and I guess thought 1/8" was plenty strong. Seems to be so far.


thekafer - 12/3/04 at 12:16 AM

quote:
Originally posted by MikeP
Bob used 3/4" OD 1/2" ID tube. I don't think he'd did a stength analysis. He needed the ID for his rod end bolt and I guess thought 1/8" was plenty strong. Seems to be so far.


I did'nt want to take any chances so I used 4130 chromoly for the whole mess.
My concern was the weld(Ok, my welding)
holding the 1/2"bolt in the end of the push rod,so I used 4ea 3/16" monel rivets 1/2" apart oriented 90 degrees from each other instead of the 2 spring pins. I made shouldered bushings out of 630 alumibronze for the rocker arm instead of thrust washers. I'm pleased to here it performs well now that I've already
made the pieces.
thanks guys! Fletch.