help please cant get it right

[jrogers80]

Ok so i drew this in autocad then imported it into fusion and now in the setup it says my models dia is 4.78" but when i check it in the design section and in autocad it is 4.5" also, i can not seem to get the model to be in the center of the stock. I am making these from 4.5" aluminum round stock. Later i will probably go to 4.75" stock but for now i need to make this work but it is not working like i want it to and I have no idea how to fix this problem.  i want my wcs to be in the center of the part with Y axis pointing straight up to a hole.

[davebYYPCU · Accepted solution]

Not a CAM guy, 

Problem is likely to be the imported articles,

The Sketch origin and the file Origins are misaligned, and the stock is picking up on the sketch origin, not the file origin.

Stock is not concentric, so the stock grows to the 4.8 ish.

I would fix it with native sketch and extrude, but....

@seth.madore maybe able to help.

[etfrench · Accepted solution]

The reason the WCS is not centered on your model when using a cylinder for the stock is the model is 5 sided.  Fusion 360 doesn't appear to be calculating the stock cylinder the way you or anyone else would expect 😣.  If you change from a cylinder to a box, the WCS will be at the center of the model.  Alternatively, add a sketch point at the circle center in sketch 'joe cap last' almost like @davebYYPCU says and use that as the WCS origin.

p.s. It would also be a good idea to fully constrain your sketch.  Are all of the arcs on the perimeter supposed to be tangent with each other? 

[TheCADWhisperer · Accepted solution]

---

@jrogers80 wrote:

Ok so i drew this in autocad ...

---

@jrogers80 

Can you Attach the original *.dwg file here?

[TrippyLighting · Accepted solution]

---

@jrogers80 wrote:

Ok so i drew this in autocad then imported it into fusion ...

---

Why ?

[jrogers80 · Accepted solution]

Because I have autocad and fusion makes me pull my hair out because it is not so user friendly for me but i keep trying because i dont want to give up on it and its really the only cam software i can afford. I know fusion has drawing capabilities but instead of just saying "WHY" why dont you help out.

[jrogers80 · Accepted solution]

Yes I did notice that when I put it on a box stock it was correct. So how should I fix it? I suck at drawing in fusion.. Autocad is much better for me right now because I know the ins and outs.

[jrogers80]

This is supposed to be an american racing wheel center.. If you know cars but if not ill post a pic. This is what happens when i try to draw in fusion. i did try to correct some things after i imported it into fusion... I am still trying to learn the ins and outs of fusion but it still frustrates me.. As much help as you are willing to give I will gladly receive.

[jrogers80]

Still learning the cam stuff.. have always written programs by hand until i started getting more complex things to do.

[jrogers80]

Here is a dxf file. and a picture of what this is supposed to be. I did not model the whole thing just the perimeter.

[TheCADWhisperer]

I was expecting a native *.dwg file.

In AutoCAD you should model with symmetry about the Origin.

In AutoCAD you should make your arcs Tangent.

I recommend that you start learning Fusion 360 and ask lots of questions.

[TrippyLighting · Accepted solution]

---

@jrogers80 wrote:

Because I have autocad and fusion makes me pull my hair out because it is not so user friendly for me but i keep trying because i dont want to give up on it and its really the only cam software i can afford. I know fusion has drawing capabilities but instead of just saying "WHY" why dont you help out.

---

Without knowing why you designed this in AutoCAD I cannot possibly provide help.

While the answer you provided is what I expected, it's still good to have some confirmation.

I am sure you already know this, but lets use the proper terminology. The usual workflow is that :

1. You start with a simple sketch, which builds the foundation for what you do next.
2. Then you use some of the 3D tools such as extrude, revolve etc. to create a 3D model
3. Then you create a manufacturing drawing.

I can assure you that I understand the pains of going from AutoCAD to a parametric constraint based sketch engine. I went from AutoCAD to SolidWorks in 1998 😉

You are only going to prolong your learning experience and thus making it that much more painful to get your head around Fusion 360 if you continue to use AutoCAD for this.

Attached is a model showing one approach on how to create this. I did not look at your DXF, so the dimensions are arbitrary. The important thing here is the workflow. IF you go through the timeline step by step, you should be able to see how I built this.

Others will share different approaches.

[jrogers80]

Sorry here you go.

[TheCADWhisperer]

The part is not modeled correctly in AutoCAD.

We can help you learn Fusion 360.

(Or if you would like to continue using AutoCAD - I can help you do it correctly in that program too.)

[jrogers80]

Thanks. I would love to learn fusion. A little background on me. I own a small mom and pop machine shop job shop. came from a fabrication background. and we always made our own parts on manual stuff.. later on when I took over i brought in cnc stuff for repeatability but nothing complicated hence the hand written programs. so now more and more customers are wanting cool complex parts but without the cam background im having trouble with fusion. I have muddled through somewhat but it takes me so long to get things right in fusion. But yes any help will be greatly appreciated and well received. I mostly use autocad for my plasma table and I know you can use fusion i think for that but i think you have to have to purchase an extension.  

[TheCADWhisperer]

---

@jrogers80 wrote:

I would love to learn fusion.

---

@jrogers80 

Step 1.  Right click on the XY plane and select Create Sketch.

Sketch the circle as shown below - being sure to click the Origin as the center point of the circle.

Dimension as shown.

File>Export the *.f3d file to your local drive and then Attach the file here in your next Reply for Step 2.

[jrogers80]

I went a little farther and put bolt holes in but you tell me if my workflow is wrong and if i should finish sketch after everything i do or keep drawing until i need to extrude... I do wonder why my small circles are not black and locked and i can not pick a tangent to make the arcs that i need.

[TrippyLighting]

Did you take a look at the model I had attached to my post ?

You'll notice that I did not include any of the small circles you have in your sketch.

If you go through the timeline you'll see why 😉

[jrogers80]

I dont see why, all i see is what you did. why wouldnt i draw the circles to the correct radius and trim them and then add in the rest of the arcs or circles and trim those?

[jrogers80]

I didnt know if you got this or not