Trailing arm - 1/4 elliptical spring question.

[boaski]

I'm doing a build starting with a 1949 Ford F5. I've been doing some test layouts of how I want build the front suspension. Following are a few pictures of how I'm planning on going. I would like some input as to whether I'll need to put in some sort of lateral link bars.

 

[Unkl Ian]

WOW ! That is one COOL design.

For lateral location,I think you will be ok without a Panhard bar.

Have you considered turning the springs around backwards ?
It would work just the same either way.

What will the new arms be made of ?

 

[Caddad65]

That's cool.

I agree. You shouldn't need a panhrd bar.

 

[boaski]

WOW ! That is one COOL design.

For lateral location,I think you will be ok without a Panhard bar.

Have you considered turning the springs around backwards ?
It would work just the same either way.

What will the new arms be made of ?

Thanks for the kind words.

The springs are the old front springs, just shortened. I flipped them to keep the pull / tension in the same direction.

The trailing arms will be an "I" beam design. The center vertical rib will be 1/2" HRS. The unit will have 3/8" HRS plates added on in the front where the spring shackle hangs and at the rear pivot point. The arm will be wrapped with 1/4" by 2" HRS flat.

My goal is to use as much as I can from the original truck.

Here it is as I found it:

Here is how it sits at the moment:

 

[Unkl Ian]

Might be cool to use part of the stock grill in front of the rad.

 

[boaski]

I started cutting out the front trailing arms today.

1/2" A36 plate on the waterjet.

Here's the layout of the parts on the PC.

Here's the parts for the 2 arms. I don't have the spacers cut for the rear of the arms yet.

I cut slots in the mounting plates as well as tabs in the bottom of the main plates. I like stuff to lock together and have a good method to locate. The 1/4" flat stock laying on top is only 1 1/2" wide. When we weld these up I'll have 2" wide flat stock. The arm assembly in the top of the picture gives you an idea of how it will go together.

I hope to start welding these up this week. I'm thinking about boring out the rear pivot holes and the spring shackle to allow me to insert a hardened bushing.

 

[Bonehead]

High tech rat rod for sure. I really like it so far.

 

[motomech]

IMO i would definatly use a panhard bar.

Reason:There is alot of un-sprung weight there.Heavy wheels/tires and axle

 

[donsrods]

A waterjet............I WANT one of those!!!!! Has to be the coolest piece of equipment ever, look at the quality of those parts.

I really, really like your project. Very different and thinking is outside the box. You need to be committed, and I mean that in the very nicest sense. Keep us posted please, this one is fun to watch for sure.

Don

 

[boaski]

A waterjet............I WANT one of those!!!!! Has to be the coolest piece of equipment ever, look at the quality of those parts.

Don

You can do some pretty cool stuff with the WJ. It is a very expensive machine to run and maintain. It seems like any problem with the pump ends up costing $1,000. But I guess anything that generates 55,000 to 60,000 psi has a lot of stress on it.

We have some parts we run out of 3/16" copper that we hold +.004" / -.005" tolerance.

I have to admit that I'm thankful to have a machine shop available to make parts. It's just hard to go back after being there all week.

Back to the truck; I'm looking at using the original rear springs and flipping them like the following picture.

I'll probably make a set of "I" beam trailing arms to match the front.

 

[bob w]

Every once in a while someone comes up with a truely unique design. This is one of those times. I have built two cars with quarter elliptic front suspensions and haven't needed panhard bars on either of them. Your rig is going to be quite a bit heavier, which might make it desireable to have one. I have one car with quarter elliptic rear suspension and I elected to put a diagonal link in. Don't know if it really needed it though.
You are under orders to keep the pictures coming. Well, not orders, but please keep us in the loop because your build is very interesting.

 

[Unkl Ian]

I would use a Bronze or Delrin bushing for the pivot.

 

[50Ford]

Awesome work! Cant wait to see more!

 

[earthman]

The more you can triangulate the arms the more resistance you will have to
lateral movement. I would think even 15 or 20 degrees should eliminate any
need for a panhard.What is your overall plan? It looks awesome at this point

 

[motomech]

The more you can triangulate the arms the more resistance you will have to
lateral movement. I would think even 15 or 20 degrees should eliminate any
need for a panhard.What is your overall plan? It looks awesome at this point

X2 on the triangulation

 

[boaski]

I finally got one of my trailing arms welded up. It looks like it will work, now I need to finish the other one & start making my spring mounting brackets.

I don't know how some of you guys get your projects done so quick. I was planning on having the thing sitting on the front and rear suspensions by winter. In all likelihood I'll be fortunate to get the front suspension holding the truck off the ground before winter.

Now it gets dark pretty early. I'm also starting to get the itch to start getting the snowmobiles ready for winter. Too many projects, too little time, too short of an attention span.

 

[Bonehead]

Those arms are KiLLeR!

You are putting in extra time making it come out really good.

 

[maddog]

Wow, heavy metal

 

[Unkl Ian]

EXCELLENT design and execution.

 

[24dodge]

that looks excellent ! great job , really interesting