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Problem with wheel rotation
I modeled a wheel it looks like this in 3ds max :
But when I add into unity it looks like this and rotates backwards:
I tried to rotate model and pivot in both programs, dosen't makes any change. File is exported as .3ds
i dunno, it's a file incompatibility. blender is good with unity. else just get the 4 wheels and change them in unity, add 90 to them or something
Answer by sparkzbarca · Oct 16, 2012 at 01:58 AM
excellent posting the blender pic it shows whats wrong.
the axises aren't lined up
in blender
blue = z axis/ forward back green = y axis/up down red = x axis left right
so the z axis should be lined up with the cars front. its lined up top to bottom
currently the top and bottom of the tire are the z axis they should be y
the x axis should be lined up with the inside and outside they are lined up front to back
align them in blender and reimport.
basically unity thinks the top of the tire is the front. the front of the tire is the side and the side of the tire is the top. but hey you told it that. :P
mark as answered, comment if you have questions but thats the answer.
program is 3ds max not blender and i can't change the axis, how to do it? And when I try to export as fbx program crashes.
you rotate the object in the program.
you can save it as any format unity will read.
look at that picture of it in 3ds max. the Y axis is the one thats green. The Y axis should run from the top of your model to the bottom. It should point from the center of your model to the sky. basically if you look at the picture and you imagine the green arrow points toward the sky what you end up with is a model of a tire on its side.
And that is exactly what you have there. A tire on its side. But you want it standing, so you need the green arrow to point up, towards a tread.
If this tire has a hubcap and stuff so it looks different viewed from the hubcap side than the non hubcap, then you need to point the red X axis towards the car. If not it doesn't matter, but basically do this.
Imagine the tire is on a car, doesn't matter which wheel it is. Point the red arrow towards the car by rotating the object.
Now the Green axis should be pointing up towards the top of the screen in 3dsmax. if you rotate so that happens the Z axis will take care of itself. The model is ready to be saved and imported.
If you don't know how to rotate an object in 3dsmax. I don't know what to tell you, you said you built the model, I assumed you knew how to rotate an object. If its your first model you may check the 3dsmax forums.
This is beginner issue and easily solved, but i don't use 3dsmax. I've no idea what the rotate keys are.
if it rotates wrong as far as turning left when it should turn right or going forwards when it should go back or going down when it should go up that has to do with the which axis you made positive and whcih you made negative in your modelling program.
for example if you have a skyscraper and the y axis is lined up with the top and bottom but the Y axis gets bigger as you go down the model then the bottom is basically the top.
Basically
on the X axis right should be the side with increasing positive numbers and left the side with increasing negative numbers.
Y axis from the middle to the top should be positive and middle to bottom negative.
Z axis, the front should be positive and the back should be negative numbers.
Your answer
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