Technical Rear buggy spring - gaps when compressed

Another rookie build question… I am mocking up my 32 roadster project; went to attach my model A style rear spring to the axle and there are significant gaps between the leaves even though the center is all the way compressed with the pin installed. Just doesn’t look right and my expectation was that all leaves would sit flat against each other.

Some notes: this is the So-Cal speed shop spring (part 00163100R) that is narrowed 3” from stock. The center-to-center spring perches on the quick change is 46”. I also removed 2 leaves from the pack (counting from the main leaf to the shortest leaf, I removed the 3rd and 5th leaves).

Before I move forward, I figured I should get some additional eyes and seasoned opinions on this. Should I just move forward as-is for mock up and assume the leaves will settle with weight? Should I put those 2 leaves I took out back in? I greased between the leaves before compressing them to help slide, but I did not chamfer them - hard to tell if they aren’t flat because of this and are digging into each other.

 

Try putting them back end and see if that remedies it. I would almost bet that it would.

 

I have a very similar sounding setup and have no obvious gaps. Mine is loaded in a running and driving steel 3w coupe that is about to be torn down for paint etc, but it's not had a full tank of gas yet. I have the same SoCal spring with no leaves removed. Perches are about 43.75" apart and the eyes on the loaded spring are 42" apart. Shackles are at 30 degrees, not the ubiquitous 45, but that's another subject! The ride feels just right. The spring required an amount of spreading to install, accomplished with ratchet straps. Not too sure how this info helps you! You might want to get the mockup complete and simulate the loads and then decide where to go from there?

Chris

 

I would not be concerned about minor gaps as long as the not at the end of the leafs. If you think they might be digging in just clean up the ends.

Phil

 

I suspect your spring was made by Posie's as that's who So-Cal was getting them from at one time. Over the years of chassis building I have encountered a similar problem with the Posie model A spring. I have talked to them about it and they say there's nothing they can do. They even replaced a spring that had a really bad gap problem with one with lesser gaps. I wish I knew the cure as it sure doesn't look right.

 

I'll borrow a coaching question: Are they unable, or unwilling to do anything?

 

Use the main leaf as a template and then bend each spring
to match the arcs of each of the other springs
as needed in a press.

 

Thanks for the replies. I am first going to add the two leaves I removed and see where that puts things. I do not know what the ride quality or ride height will be with a full set of leaves, though. I was just taking an educated guess on removing two leaves for a light roadster based on searches here and the Bishop/Tardel book.

If the gaps remain with the full set of leaves, I am not sure what to do. I do not have a press, nor access to one. I am also into this spring some additional $$$ already because I had to have brass bushings specially turned down at a spring shop to fit the oddball 0.77” spring eye openings and oddball .55” shackle bolts (the quality of re-pop stuff is truly disappointing in some cases). I wouldn’t want to spend more on labor at the spring shop to have them press out any remaining gaps.

 

If “they” is So-Cal - I don’t expect anything from them. I already have an unanswered inquiry out to them about the spring eye size on this spring.

 

I was actually thinking of Posies, or whoever made the spring. I've heard of Posies springs causing a car to sit crooked too. And their reply was they're all like that, or nobody else complained, or some such. Not much help. Basically take it or leave it. There's really not much a retailer can do about product manufacturing issues, other than exchange or refund.

 

Perhaps there is a HAMBer in MA near you who will let you use his press and give you a hand.

 

WTF??? That ain't right! Send a picture to So-Cal and ask what they are going to do about it... and press them hard about it!! Totally unacceptable and junk. From off-shore I bet. Get your $$ back and have a REAL spring spring made by a REAL local spring maker. Even if the leaves 'settle' the spring rate won't be right due to uneven loading of each leaf.
My aching ass, what a mess!

 

Your picture doesn't show the spring ends, shackles, or spring hangers. Without that info, my guess would be maybe the main leaf is too short (eye to eye). Your title says compressed, it really isn't. The more it's spread the flatter it will become. Because the spring is unloaded
the other leaves aren't flattened, so maybe with a lode the other leaves may flatten as well.

 

I've fit springs all my life and those truely suck.

They are not fit right. When a spring is free there should be a gap between each leaf and as the leaves go down in size in the stack that gap should slowly get smaller too.

With that many leaves you should have about 3/4 gap between main leaf and next leaf then slowly dwindle down from there.

That FIT is important !!! Thats how the leaves evenly distribute the load between themselves and sit level.

Here's a spring pack I did for the back of 31 tudor for quarter elliptical springs. The fit is identical through all leaf springs...

Amd when that is done properly then when the spring is screwed together you will get a true fit and tight spring pack that works properly, rides good and sits level.

 

Here is the full picture. I wish I took the eye to eye measurement before I put the main leaf on…but I do not have that number.

 

So I blew it apart and snapped a pic of the set up without any clamp pressure on it. This is with the two leaves taken out as mentioned previously.

 

And here is the uncompressed setup with all leaves present. I’ll attempt to clamp these down and check if the gaps are present after the family vacation this week. I’m mentally preparing myself to have to junk this spring and find another if these leaves won’t flatten out for me.

 

Thanks for the info. I have a bad feeling that this spring just doesn’t fit….

 

Here's a picture of my 37-40 rear end. The spring hanger width is 48 1/4", unfortunately I don't have a
dimension of a model A spring. Mine is stock width with the eyes reversed. Maybe someone can measure one.
With the weight on the spring the shackles should look something like the second pic.

 

Did you put them back the same way as you pulled them out, or were some inadvertently turned 180* ?
What does it look like with the G clamps removed ?
I would pull it out and start again to see how they line up in shape, seeing how the shape of the two removed leaves have affected it !

Some are being critical of SoCal, but what did it look like before you pulled it to bits, surely if something was wrong, you would have noticed it ?

 

Lot of members in MA that could help you out if they knew where you are. That state is pretty big.

 

Thank you. This is the flat and even look I was expecting from mine.

 

I did not make note of the orientation of the removed leaves, so I could have easily made a 180 rotation. Here is a pic I found of the spring pre-mock up. Everything was flat and even. I did not notice any glaring defects at all.

 

Good thought. I am about 15 min north of Boston. I’ll update my specs to reflect that.

 

I contacted Posies about removing leaves from their rear Model A spring. They told me to start at the top leaf and remove the leaves in order. If you skip leafs the next bottom leaf is unsupported . I think this is especially true with the longer ones.

John

 

I would do as clem suggested and I counted the leaves in Blake 27s pic ; I believe he removed the top 2 leaves.
On my 41 pickup , I used rachet straps around the frame and rear end to compress the rear spring to simulate (guesstimate) ride height, but I haven't removed any leafs from the spring yet. I think you have to wait until the car is on the suspension ( full weight ) plus some driving time to see where it's going to settle before you can remove leafs. The 40/45 deg shackle angle is an important guide line on a " buggy spring" suspension. I wouldn't ignore it.

The shackle on my truck is about 30 deg. right now and the rear needs to come down about 4". I expect to remove 2 leafs eventually. On my avatar , I started with 1.5" lowering blocks in the rear ( parallel springs) and after 2 years of full weight on the springs and one year of driving ( 1500 mi ) it has 3/4 " blocks in the rear. BTW I would add something between the spring leafs to allow them to work easier. JMHO

 

The Posie's rear spring in my Tudor made the car sit low on the left side. Didn't have any gaps, though. Several members on here suggested switching the spring left to right, or doing that with individual leafs. Fortunately, it corrected by removing the entire spring ( a lot of work) and turning it end for end, and then sat level.

 

The cure is work. The curvature of the leaves do not match the main leaf or even each other. To cure the problem you tear the spring down and adjust the curve of the leaves.

One would think that the spring will settle out with driving, this will cause significant drop in ride height often called settling. This will need to be dealt with later if that is the case. I would deal with it now and cross the manufacturer off of my lost of people to buy from.

 

Agreed but the pic in post #23, supported by the text, confirms the spring was OK to start with. Looks like the spring needs to be unfucked with and then reinstalled. Jury is out on the perch width though.

Chris

 

I finally got a chance to add back those 2 leaves and clamp things down again. I still have some gaps, but not as significant. It took A LOT of force in the form of a 2-foot pipe as leverage on the clamp handles to cinch the leaves together.

Not sure what to do from here. Either stick it under the frame and move forward with the mock-up; hoping additional weight and time will flatten those leaves out. OR blow it apart again, ditch this buggy spring (along with the $ spent on custom-turned bushings…) and start over with a new spring from a reputable local hot rod shop that specializes in early Ford. Maybe even have them fit it on my axle to ensure all is correct. Thoughts?