Trouble making leaf springs

Unfortunately what fits in CAD doesn't mean it has to fit in real life. Why don't you start from either the Atruck one or the pickup truck suspension? you can copy it and make small changes checking that everything works? if you do it slowly from something that exists you will learn more than attempting it in one go and expecting it to work.

That's basically what I did. I took the atruck leaf spring example file and just changed the geometry of it (the plot points and overall lengths) and it won't build, so while I'm guessing the problem must somehow lie there, the errors it gives me don't really give me an idea of what to look for. The dimensions I have aren't that far off from what is in the atruck example spring as far as overall sizes, but the spring I have is a fair deal more flat and thick. It would be nice if the software offered a little more guidance (something like overall length not compatible with plot points) or something to that effect instead of just the "failure to build" error message.

 

I did have one thing come to mind though. For the plot points for the spring, are those supposed to be at the free loaded state? I think the points I pulled off of CAD are at the curb loading already, so that would be one more thing to try at least. It's not clear in the documentation what you are supposed to use, but I just realized that's the default model that opens when I look at the springs.

it seems you are changing all parameters in one go. Have you tried changing one at a time, test it and attemp the next parameter? it may take longer but at least you can eventually understand where the issue is

I'm not sure what you mean by "all parameters". I have to change all the plot points at once because that's not really something you can change one at a time or the shape doesn't work. The only values I am changing are the ones in the red boxes below. I'm not touching anything else, just the shape and length of the spring.

Okay, I managed to get a leaf to generate with my dimensions by building it up one leaf at a time, but I still have a few questions regarding some of the values in the leaf spring builder as the descriptions are a bit vague. The "reference marker to leafpack" description makes it sound like you need to put in a negative number if you have an overslung axle, but the sample leafspring included in the atruck package has a positive value here even though the leaf is overslung. The more complete description in the help file ("This is the vertical distance between reference marker (center of Axle) and leafpack surface (bottom of an overslung leaf or the top of the underslung leaf). This value is positive for Underslung LeafSpring and negative for Overslung LeafSpring.") again makes it sound like you are supposed to put in a negative value, but I'm wonder if selecting "overslung" in the axle mount type box just automatically treats this value as negative? I've tried putting both values in, but neither way seems to change the way the spring looks after regenerating.