Another radius arm build

[highlander]

Nice work, Chuck! I couldn't tell for sure did you notch the reciever tube or the radius arm where they overlap?

[PhantomEB]

Can you show me pics of how you mean, Aaron??

[buknbronco]

Nice work Chuck, good to see those arms go to good use.

[Daddy4zack]

Can you show me pics of how you mean, Aaron??

Here ya go..

Aaron

[PhantomEB]

Gotcha, THANKS!

[69GHOST]

FAMILYMAN you got those arms installed yet. Hope you don't mind me using your idea to build a set just like those, took your advise and ordered the 2.63 joints from ballistic they should be here tuesday thanks again.

[Familyman]

Been on vacation so let me see if I can get some answers.

The welder is a Miller 175, C25 gas and Lincoln super arc wire (really like this wire)

The shock mount I placed in the stock location since the rig its going on has a stock shock mount and I can add one later if he has that problem. Thanks for the heads up and the pic of that mount.

Highlander I notched the square tube . The old radius arm is cut about 16" from the "C". Then I cut off the top and bottom of the "I" beam so there is a 1.5" spine coming back for about the last 6" of the arm. The part furthest from the "C". Then I had to find where the "I" beam had 2" between the top and bottom so that the square tube could slide inbetween the top and bottom of the "I". Than the square tube had a 1/2" grove cut up the middle on top and bottom to match the "I" beam and then the end has a matching curvature of the end of the "C". So there is accually about 6" of spine going past the part of the stock arm you see into the center of the tube and the part you can see is fit together in an interlocking manner. I like it this way because now the weld just allows the metal to do its job vs. the weld being responsible for the strength of the arm.

I added a pic - the yellow represents the stock arm or whats left of it.
The red arrow shows some of the cut in the tube and the strait line represents the cut through the tube to allow the it to slide onto the radius arm.

FM <><

PS imagine my frind likes them
Made for a good 40th for him.
I hope he can someday join us on a run..

[Familyman]

UH pic?

[Delta 4 Wheel]

I like these Chuck. I would spend the extra time to weld a plate into the C-section of the arm to help distribute the load away from the wrist area. I failed to do this on my home built ones and subsequestly broke the radius arm in half. I built a set for a friend of mine and his snapped as well.These are the one I built after the extra plating. It is hard to see, but most of the original radius arm is plated.

[PhantomEB]

The stock arms are Cast steel, if I am correct?

[highlander]

The stock arms are Cast steel, if I am correct?

They are forged.

[Efibroncoman]

Is it okay to weld the steel reciever hitch tubing to stock radius arms with a wire feed? Or should I use a stick welder with nickel rod. I am just asking because I have heard a few horror stories of homemade arms breaking where they were welded to the stock part.

[Daddy4zack]

Is it okay to weld the steel reciever hitch tubing to stock radius arms with a wire feed? Or should I use a stick welder with nickel rod. I am just asking because I have heard a few horror stories of homemade arms breaking where they were welded to the stock part.

I think we have all used the wire feed.. "Mig" .035 W/ Argon CO2 mix gas..

Aaron

[Lars]

the only thing you may want to consider is putting the shock mounts on the side of the arms. I had binding on the shock with the mounts on the very top of the arm during full stuff. I have added mounts to the side of my arms and it frees up the shock.

Aaron

Just spotted this thread. I've been hiding out due to too many personal projects. Which is not to say that my Bronco has been gathering dust in the garage (in Davis, that doesn't take very long) but time on the computer is time away from the home remodel, airplane build, keeping kid in high school, etc...

One thing to keep in mind about shock mounts, and something that affected my thinking when I built a few sets of extended arms: shocks with rubber bushings at the ends, for example Ranchos, can handle a lot less misalignment than the fancy high dollar pieces such as Bilsteins, Fox Shox, etc. I happen to be have a set of Fox reservoir shocks with 7/8" shafts, with custom (extremely stiff) valving. Bind is not an issue due to heim joints top & bottom. But there is no way the Ranchos I've had previously could have handled the misalignment that these shocks experience at full droop or full stuff.

[Efibroncoman]

After reading this thread I decided I liked the idea of the square tube radius arms. I bought the 2" square tube and some 3" Ballistic joints. I have built my arms and they are all finish welded 42" from middle of joint to middle of "C". The problem I have is when I get the arms attached to my '79 HP Dana 44 w/ 2 degree C-bushings, and the axle is set at 5 degrees back for caster. The arms are perfectly level, 0 degrees. If I move the arms up to the frame where I would weld the link brackets, the caster angle moves to 5 degrees forward. So it looks like I need to cut a wedge and put a 10 degree up-angle in each arm. So the question I have is would the arms be weaker if I just cut the arm into two pieces(rather than cutting 3 sides), then butt welded the 2" square tube and plated the sides?